Heat-dissipating fan

Abstract

A heat-dissipating fan for electronic equipment has a frame, a stator, an impeller, a top cover and an enlarged discharge port. The frame has a bottom, a sidewall and a volute. The sidewall is formed on the bottom and has an open front and a top surface that is either parallel to or diverges from the bottom of the frame toward the open front. The volute is defined inside the sidewall. The stator is mounted on the bottom in the frame. The impeller is mounted rotatably on the stator inside the frame. The top cover is mounted on the sidewall and has an inlet and an optional recessed segment. The enlarged discharge port reduces the back pressure on air passing through the volute.

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a fan, and more particularly to a heat-dissipating fan mounted inside electronic equipment to keep electronic components such as a central process unit (CPU) or a hard drive (HDD) from overheating.

[0003] 2. Description of Related Art

[0004] In general, electronic components such as chips or power supplies inside electronic equipment generate heat that damages the electronic components and even causes them to fail. Therefore, single or multiple fans are mounted inside the equipment to keep the components from overheating.

[0005] With reference to FIGS. 6 and 7, a conventional fan (90) for electronic equipment in accordance with prior art has a frame (91), a top cover (92), a stator and an impeller (96).

[0006] The frame (91) has a bottom, a sidewall and a volute (94). The bottom has an inside surface and an outer edge. The sidewall is formed on the inside surface of the bottom flush with the outer edge and has a top surface, a front, a right side, a left side and a discharge port (95). The discharge port (95) is formed in the front of the sidewall. The volute (94) is formed inside the sidewall and communicates with the discharge port (95) in the sidewall.

[0007] The top cover (92) is mounted on the top surface of the sidewall of the frame (91) to enclose the volute (94) and has a bottom surface and an inlet (93). The bottom surface of the top cover (92) and the inside surface of the bottom of the frame (91) are separated by a distance (a). The inlet (93) is formed through the top cover (92) and communicates with the volute (94).

[0008] The stator is mounted securely on the bottom of the frame (91) in the volute (94), is aligned with the inlet (93) and has motor coils (not shown). The motor coils are selectively connected to a source of electricity (not shown).

[0009] The impeller (96) is mounted rotatably and concentrically on the stator and has permanent magnets (not shown) and multiple blades. The permanent magnets interact with the motor coils in the stator when the motor coils are connected to a source of electricity and rotate the impeller (96) on the stator. When the impeller (96) rotates, the blades draw ambient air through the inlet (93) into the volute (94) and push the air in the volute (94) out through the discharge port (95).

[0010] To reduce the back pressure on the air in the volute (94), the transverse cross sectional area of the volute (94) broadens gradually from the right side of the sidewall to the discharge port (95).

[0011] However, the distance (a) is constant throughout the volute (94) and is an absolute limit to the broadening of the volute (94) as it approaches the discharge port (95).

[0012] To overcome the shortcomings, the present invention provides a heat-dissipating fan to mitigate or obviate the aforementioned problems.

SUMMARY OF THE INVENTION

[0013] The main objective of the invention is to provide a heat-dissipating fan for electronic equipment, which dissipates heat efficiently.

[0014] A heat-dissipating fan for electronic equipment in accordance with the present invention comprises a frame, a stator, an impeller, a top cover and an enlarged discharge port. The frame has a bottom, a sidewall and a volute. The sidewall is formed on the bottom and has an open front and a top surface that is either parallel to or diverges from the bottom of the frame toward the open front. The volute is defined inside the sidewall. The stator is mounted on the bottom in the volute. The impeller is mounted rotatably on the stator inside the frame. The top cover is mounted on the sidewall and has an inlet and at least one recessed segment. The inlet is aligned with the impeller. When the top of the sidewall is parallel to the bottom of the frame, the recessed segment is formed adjacent to and forms part of the enlarged discharge port and increases the cross sectional area of the volute near the discharge port. The enlarged discharge port and cross sectional area of the volute reduce the back pressure on air passing through the volute.

[0015] Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is an exploded perspective view of a first embodiment of a heat-dissipating fan for electronic equipment in accordance with the present invention;

[0017] FIG. 2 is a top view of the fan in FIG. 1;

[0018] FIG. 3 is a side view in partial section of the fan in FIG. 1;

[0019] FIG. 4 is a side view in partial section of a second embodiment of a heat-dissipating fan for electronic equipment in accordance the present invention;

[0020] FIG. 5 is a top view of a third embodiment of a heat-dissipating fan for electronic equipment in accordance the present invention;

[0021] FIG. 6 is a top view of a top view of a conventional heat-dissipating fan for electronic equipment in accordance with the prior art.

[0022] FIG. 7 is a side view in partial section of the fan in FIG. 6.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

[0023] With reference to FIGS. 1, 4 and 5, a heat-dissipating fan in accordance with the present invention comprises a frame (10, 10a), a stator (14), an impeller (20), a top cover (30, 30a, 30b) and an enlarged discharge port (50, 50a, 50b).

[0024] The frame (10, 10a) has a bottom (11), a sidewall (12, 12a, 12b) and a volute (13). The bottom (11) has an inside surface and an outer edge. The sidewall (12, 12a, 12b) is formed flush with the outer edge on and extends up from the inside surface of the bottom (11) and has a top surface, a left side, a right side, a back and an open front. The top surface is either parallel with the bottom (11) or diverges from the bottom (11) toward the open front and has multiple mounting protrusions (121). With further reference to FIG. 5, the right side of the frame (10b) is optionally open. The volute (13) is formed inside the sidewall (12, 12a, 12b), communicates with the open front of the sidewall (12, 12a) and the open right side of the sidewall (12b) and has a height defined between the bottom surface of the top cover and the inside surface of the bottom (11) of the frame (10).

[0025] The stator (14) is mounted securely on the inside surface of the bottom (11) of the frame (10) inside the volute (13) and close to the right side of the sidewall (12, 12a, 12b).

[0026] The impeller (20) is mounted rotatably on the stator (14) inside the volute (13) and has multiple blades.

[0027] The top cover (30, 30a, 30b) is mounted on the top surface of the sidewall (12) to enclose the volute (13) and has a front edge, a bottom surface, an inlet (31), at least one recessed segment (32) and mounting holes (33). The inlet (31) is defined through the top cover (30) and communicates with the volute (13).

[0028] The enlarged discharge port (50, 50a) is formed from the open front of the sidewall and the top cover, communicates with the volute (13) and has a height. The height of the discharged port (50, 50a) is defined between the front edge of the top cover (30, 30a, 30b) and the inside surface of the bottom (11) of the frame (10, 10a) and is larger than the height of the volute (13).

[0029] With further reference to FIGS. 2 and 3, the recessed segments (32) are formed in the bottom surface of the top cover (30, 30a, 30b) adjacent to the inlet (31) and the discharge port (50, 50a, 50b). The recessed segments (32) become progressively deeper as the recessed segments (32) approach the open front of the sidewall (12, 12a, 12b). When the right side of the sidewall (12b) is open, the recessed segment (32b) corresponds to the open front and the open right side of the sidewall (12b).

[0030] The mounting holes (33) are defined through the top cover (30, 30a, 30b), correspond to and respectively hold the mounting protrusions (121) of the sidewall (12, 12a, 12b).

[0031] In first and third embodiments of the heat-dissipating fan in accordance with the present invention, the discharge ports (50, 50a) are formed from the open front of the sidewall (12) and one of the recessed segments (32, 32b) in the bottom surface of the top cover (30, 30a) and communicate with the volute (13). In the third embodiment of the heat-dissipating fan in accordance with the present invention, another one of the discharge port (50b) is formed from an opening in the right side wall and a recessed segment (32b) in the bottom of the top cover (30b) and communicates with the volute (13). One discharge port (50) is formed in the front and another discharge port (50b) may be formed in the right side.

[0032] The enlarged discharge ports (50, 50a, 50b), the recessed segments (32, 32b) in the top cover (10, 10b) and the diverging top cover (30a) help the broadening the volute (13) and allow air to blow out of the frame (10, 10a, 10b) more efficiently. Therefore, the cooling effective of the heat-dissipating fan is improved.

[0033] Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

Claims

1. A heat-dissipating fan comprising: a frame having a bottom having an inside surface; and an outer edge; a sidewall formed flush with the outer edge on and extending up from the inside surface of the bottom and having a top surface, a left side, a right side, a back and an open front; and a volute formed inside the sidewall and communicating with the open front of the sidewall and having a height defined between the bottom surface of the top cover and the inside surface of the bottom of the frame; a stator mounted securely on the inside surface of the bottom of the frame inside the volute and close to the right side of the sidewall; an impeller mounted rotatably on the stator inside the volute and having multiple blades; a top cover mounted on the top surface of the sidewall and having a front edge; a bottom surface; and an inlet defined through the top cover and communicating with the volute; and an enlarged discharge port formed from the open front of the sidewall and the top cover, communicating with the volute and having a height defined between the front edge of the top cover and the inside surface of the bottom of the frame and larger than the height of the volute.

2. The heat-dissipating fan as claimed in claim 1, wherein the top surface of the sidewall diverges from the bottom of the frame toward the open front.

3. The heat-dissipating fan as claimed in claim 1, wherein the top surface of the sidewall is parallel with the bottom of the frame; and the bottom surface of the top cover has a recessed segment formed adjacent to the inlet.

4. The heat-dissipating fan as claimed in claim 1, wherein the right side of the sidewall of the frame is open and communicates with the volute to form a discharge port.

5. The heat-dissipating fan as claimed in claim 1, wherein the sidewall further has multiple mounting protrusions formed on the top surface of the sidewall; and the top cover further has multiple mounting holes defined through the top cover, corresponding to and respectively holding the mounting protrusions of the sidewall.

6. The heat-dissipating fan as claimed in claim 2, wherein the right side of the sidewall of the frame opens and communicates with the volute to form a discharge port.

7. The heat-dissipating fan as claimed in claim 3, wherein the right side of the sidewall of the frame opens and communicates with the volute to form a discharge port.

8. The heat-dissipating fan as claimed in claim 3, wherein the number of the recessed segment is two and the recessed segments becoming progressively deeper as the segments approach the open front.