BACKGROUND
The invention relates to a heat-dissipation structure for a motor, and in particular to a heat-dissipation structure for a fan motor.
A motor is an active driving device for actuating an impeller to produce airflow to dissipate heat. Centrifugal and axial-flow fan motors are two major types of motors.
In FIG. 1A, a conventional centrifugal fan motor 1 comprises a rotator 10, an impeller 11 and a motor (not shown). The impeller 11 is installed on the rotator 10 driven by the motor. As the rotator 10 is actuated, the impeller 11 thereon is synchronically rotated to produce airflow for heat dissipation. In FIG. 1B, a conventional axial-flow fan motor 2 comprises a rotator 20, an impeller 21, a frame 22 and a motor (not shown). The impeller 21 is installed on the rotator 20 driven by the motor, and the rotator 20 and the impeller 21 are enclosed by the frame 22. As the rotator 20 is actuated, the impeller 21 thereon is synchronically rotated to produce airflow for heat dissipation, and airflow therein can be efficiently collected by the frame 22.
Heat generated by the interior of the rotator 10 or 20 over a long period of operation, however, cannot be dissipated to an exterior. Thus, the motor is easily overheated and the life thereof is reduced.
To solve this problem, two centrifugal fan motors 3 and 4 shown in FIGS. 2A and 2B are provided by forming a plurality of through holes on a rotator thereof.
In FIG. 2A, the fan motor 3 comprises a rotator 30 formed with a plurality of through holes 300, an impeller 31 and a motor (not shown). The impeller 31 is installed on the rotator 30 and driven by the motor. As the rotator 30 is actuated, the impeller 31 thereon is synchronically rotated to produce airflow for heat dissipation. Heat generated from the rotator 30 can be efficiently dissipated to the exterior via the through holes 300.
In FIG. 2B, the fan motor 4 comprises a rotator 40 formed with a plurality of through holes 400, an impeller 41, a frame 42 and a motor (not shown). Heat generated from the rotator 40 can also be efficiently dissipated to the exterior via the through holes 400 as the rotator 40 is actuated.
Dust or particles cannot be completely stopped from entering the fan motors 3 and 4 via the through holes 400 and 500, however, thus a shaft of the fan motors 3 and 4 tend to be obstructed by dust or particle accumulation reducing average life thereof.
SUMMARY
The invention provides a heat-dissipation structure for a motor to dissipate heat to the exterior and prevent particles from entering therein.
The heat-dissipation structure comprises a seat and a rotator. The rotator coupled to the seat by a shaft comprises a cylindrical housing and a cover. The housing has an inner side connected to the shaft and a bottom comprising at least one through hole. The cover covers the housing and positioned apart from the housing by a distance. Thus, the cover prevents objects such as dust or particles from entering via the through hole as the rotator is rotated, and the generated heat is efficiently dissipated to the exterior.
The cover of the invention is connected to the exterior of the bottom of the housing via a plurality of radially arranged guiding blades, and at least one through hole is formed between any two adjacent guiding blades. The cover is connected to the exterior of the bottom of the housing via a bar, and the housing is integrally formed with the cover and the guiding blade as a single piece.
In a embodiment, the housing of the heat-dissipation structure comprises a first part and a second part connected to the first part. An inner side of the first part is connected to the shaft, and at least one through hole is formed on a bottom of the first part, and the second part is connected to the cover via the guiding blade, and a distance is formed between the cover and the second part.
The heat-dissipation structure is employed on a fan structure, and the heat-dissipation structure further comprises an impeller surrounding the rotator. Thus, the impeller is rotated together with the rotator. The fan structure is a centrifugal fan or an axial-flow fan structure.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
FIG. 1A is a perspective view of a conventional centrifugal fan motor.
FIG. 1B is another perspective view of a conventional centrifugal fan motor.
FIG. 2A is another perspective view of a conventional centrifugal fan motor.
FIG. 2B is another perspective view of a conventional centrifugal fan motor.
FIG. 3A is a perspective view of a centrifugal fan motor according to the invention.
FIG. 3B is a perspective view of a rotator of the centrifugal fan motor of the invention.
FIG. 3C is a sectional view of the rotator of the centrifugal fan motor of the invention.
FIG. 3D is an exploded view of a housing of the centrifugal fan motor of the invention.
DETAILED DESCRIPTION
FIGS. 3A and 3B are two perspective views of a centrifugal fan motor 5 of an embodiment of the invention, and FIG. 3C is a sectional view of the centrifugal fan motor 5.
In FIG. 3A, the centrifugal fan motor 5 comprises a rotator 50, an impeller 51 and a seat 55. In FIG. 3C, the rotator 50 is coupled to the seat 55 by a shaft 56, and the impeller 51 surrounds the rotator 50. Thus, the impeller 51 rotates with the rotator 50, forming an active airflow to dissipate heat generated from a heat source (not shown). The rotator 50 comprises a cover 501, at least a guiding blade 502 and a housing 505. In this embodiment, the housing 505 in rounded and cylindrical. It is to be understood that the invention is not limited thereto the disclosed embodiments. The housing 505 can be formed by any desired sectional shapes. A central region of an inner side of the housing 505 is substantially connected to the shaft 56, and at least one through hole 500 is formed on a bottom of the housing 505. In this embodiment, the bottom of the housing 505 comprises a plurality of through holes 500. The cover 501 is connected to an exterior of the bottom of the housing 505, and a distance “d” is formed between the cover 501 and the housing 505. In the embodiment, the cover 501 is connected to the exterior of the bottom of the housing 505 via a plurality of guiding blades 502 arranged radially and outwardly and with respect to the center of the shaft 56. In other embodiments, a bar (not shown) or the like can be used to connect the cover 501 to the exterior of the bottom of the housing 505. Another embodiments, the shaft 56 is connected to the cover 501 directly (not shown), and the cover 501 is connected to the housing 505 via a plurality of guiding blades 502. The guiding blade 502 can be a flat plate (FIG. 3D) or an arc plate (not shown in FIGS.). The size of the cover 501 is designed to be large enough to overlap all through holes 500 formed on the bottom of the housing 505.
As the centrifugal fan motor 5 is actuated, the impeller 51 rotated by the rotator 50 produces an airflow pressure difference, and airflow moves in a direction 60 in FIG. 3C. The flow rate of airflow at the exterior of the housing 505 is larger than the flow rate of airflow inside of the housing 505. It is understood that airflow inside of the housing 505 is expelled to the exterior of the housing 505 from the through hole 500 via the distance “d” based on the Bernoulli's Principle. Also, a heat generated in the housing 505 is expelled to the exterior in the same way in a direction 61 of FIGS. 3B and 3C.
Thus, with the guiding blades 502 arranged outwardly and radially connect the cover 501 to the exterior of the bottom of the housing 505, airflow inside of the housing 505 is effectively and efficiently expelled to the exterior by the rotating guiding blades 502, increasing heat-dissipation efficiency. Alternatively, when the cover 501 overlaps all through holes 500 on the bottom of the housing 505, objects such as dust or particles are completely stopped from entering the housing 505 via the through holes 500, so that the shaft 56 is prevented from being obstructed and thus its average life thereof increases.
In FIG. 3D, a housing 505′ of an embodiment comprises a first part 506 and a second part 507 connected to the first part 506. In other embodiments, the rotator 50 can be integrally formed into a single piece. The inner side of the first part 506 is connected to the shaft 56, and the through holes 500 are formed on a bottom of the first part 506, and the second part 507 is connected to the cover 501 via the guiding blades 502. The guiding blades 502 are connected to an edge of the cover 501 to form a distance is formed between the cover 501 and the second part 507, so that the assembled first part 506 and second part 507 of the housing 505′ still has the same effect as the housing 505.
It is noted that all features of the invention can be applied in an axial-flow fan structure (not shown) and any kind of motor, especially for an axial-flow fan structure equipped with a frame (not shown).
While the invention has been described with respect to preferred embodiment, it is to be understood that the invention is not limited thereto the disclosed embodiments, but, on the contrary, is intended to accommodate various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
Patent Application
20060051221
