[0001] The invention relates to a fan device, and more particularly to a fan device capable
of producing enhanced air pressure.
[0002] In order to enhance air pressure, a stator impeller is applied to a fan. The stator
impeller is mounted to a fan housing of the fan, and includes a plurality of angularly
equidistant stator blades. An air-guiding channel is formed between an adjacent pair
of the stator blades. When a fan impeller of the fan is driven to rotate, air flowing
from the air inlet is guided by the stator impeller to flow toward the fan impeller
through the air-guiding channels, thereby enhancing air pressure produced by the fan.
As a result, increased airflow amount can be attained. However, in such a configuration,
greater acoustic noise occurs during rotation of the fan impeller at a speed within
a certain speed range.
[0003] Therefore, an object of the present invention is to provide a fan device that can
produce enhanced air pressure and increased airflow amount with reduced acoustic noise.
[0004] According to the present invention, a fan device comprises:
a fan housing configured with a receiving space and having a bottom wall formed with
an air inlet in spatial communication with the receiving space, a top wall formed
with an air outlet in spatial communication with the receiving space, and a surrounding
side wall transverse to and interconnecting the top and bottom walls, and cooperating
with the top and bottom walls to define the receiving space thereamong;
a fan impeller mounted in the receiving space in the fan housing, disposed adjacent
to the air outlet in the top wall of the fan housing, and operable to rotate about
a central axis that is transverse to the top and bottom walls of the fan housing;
and
an air-guiding unit mounted fixedly in the receiving space in the fan housing and
disposed adjacent to the air inlet in the bottom wall of the fan housing, the air-guiding
unit including a center connecting member disposed coaxially with the central axis,
and a plurality of air-guiding blades angularly spaced apart from each other and interconnecting
the central connectingmember and the surrounding side wall of the fan housing, an
angular distance between each adjacent pair of the air-guiding blades being different
from that of any other adjacent pair of the air-guiding blades.
[0005] Other features and advantages of the present invention will become apparent in the
following detailed description of the preferred embodiments with reference to the
accompanying drawings, of which:
Figure 1 is a schematic bottom view showing the first preferred embodiment of a fan
device according to the present invention;
Figure 2 is a perspective view showing the first preferred embodiment without a fan
impeller;
Figure 3 is a partly schematic sectional view showing the first preferred embodiment;
Figure 4 is a plot illustrating experimental measurement results of acoustic noise
generated by the prior art and the first preferred embodiment;
Figure 5 is a schematic top view showing the second preferred embodiment of a fan
device according to the present invention without a fan impeller;
Figure 6 is a schematic top view showing a variation of the second preferred embodiment;
and
Figure 7 is a schematic top view showing the third preferred embodiment of a fan device
according to the present invention.
[0006] Before the present invention is described in greater detail, it should be noted that
like elements are denoted by the same reference numerals throughout the disclosure.
[0007] Referring to Figures 1 to 3, the first preferred embodiment of a fan device according
to the present invention is shown to include a fan housing 1, a fan impeller 2, and
an air-guiding unit 3.
[0008] The fan housing 1 is configured with a receiving space 10, and has a bottom wall
11, a top wall 12 and a surrounding side wall 13. The bottom wall 11 is formed with
an air inlet 111 in spatial communication with the receiving space 10. The top wall
12 is formed with an air outlet 121 in spatial communication with the receiving space
10. The surrounding side wall 13 is transverse to and interconnects the top and bottom
walls 12, 11, and cooperates with the top and bottom walls 12, 11 to define the receiving
space 10 thereamong.
[0009] The fan impeller 2 is mounted in the receiving space 10 in the fan housing 1, is
disposed adjacent to the air outlet 121 in the top wall 12 of the fan housing 1, and
is operable to rotate about a central axis (X) that is transverse to the top and bottom
walls 12, 11 of the fan housing 1. In this embodiment, the fan impeller 2 includes
a hub body 21, and a plurality of fan blades 22 extending outwardly and radially from
the hub body 21. In this embodiment, the fan blades 22 are angularly equidistant.
[0010] The air-guiding unit 3 is mounted fixedly in the receiving space 10 in the fan housing
1, and is disposed adjacent to the air inlet 111 in the bottom wall 11 of the fan
housing 1. The air-guiding unit 3 includes a center connecting member 31 disposed
coaxially with the central axis (X) , and a plurality of air-guiding blades 32 angularly
spaced apart from each other and interconnecting the central connecting member 31
and the surrounding side wall 13 of the fan housing 1. An angular distance (
θ) between each adjacent pair of the air-guiding blades 32 is different from that of
any other adjacent pair of the air-guiding blades 32. In this embodiment, the center
connecting member 31 includes a circular cap body 312, and a tube body 311 extending
integrally from the cap body 312 toward the hub body 21 and disposed coaxially with
the central axis (X).
[0011] In operation, when the fan impeller 2 is driven to rotate, air flowing from the air
inlet 111 is guided by the air-guiding blades 32, and then flows toward the air outlet
121, as indicated by solid-line arrows in Figure 3.
[0012] In sum, due to the presence of the air-guiding unit 3, the fan device of the present
invention can produce enhanced air pressure, thereby resulting in increased airflow
amount. It is noted that, since the angular distances (
θ) are different from each other, the fan device of the present invention generates
reduced acoustic noise during operation as compared to the prior art, as shown in
Figure 4.
[0013] Figure 5 illustrates the second preferred embodiment of a fan device according to
this invention, which is a modification of the first preferred embodiment. Unlike
the first preferred embodiment, the air-guiding unit 3' further includes a plurality
of auxiliary air-guiding blades 33 extending inwardly and radially from the surrounding
side wall 13 of the fan housing 1 toward the central connecting member 31. Each auxiliary
air-guiding blade 33 is disposed between a corresponding adjacent pair of the air-guiding
blades 32, and is spaced apart from the corresponding adjacent pair of the air-guiding
blades 32 and the central connecting member 31. In this embodiment, the auxiliary
air-guiding blades 33 have the same length.
[0014] Figure 6 illustrates a variation of the second preferred embodiment, wherein each
of the auxiliary air-guiding blades 33 of the air-guiding unit 3' has a length different
from that of any other one of the auxiliary air-guiding blades 33.
[0015] Figure 7 illustrates the third preferred embodiment of a fan device according to
this invention, which is a modification of the first preferred embodiment. Unlike
the first preferred embodiment, an angular distance (
φ) between each adjacent pair of the fan blades 22 is different from that of any other
adjacent pair of the fan blades 22.
1. A fan device
characterized by:
a fan housing (1) configured with a receiving space (10) and having a bottom wall
(11) formed with an air inlet (111) in spatial communication with said receiving space
(10), a top wall (12) formed with an air outlet (121) in spatial communication with
said receiving space (10), and a surrounding side wall (13) transverse to and interconnecting
said top and bottom walls (12, 11), and cooperating with said top and bottom walls
(12, 11) to define said receiving space (10) thereamong;
a fan impeller (2) mounted in said receiving space (10) in said fan housing (1), disposed
adjacent to said air outlet (121) in said top wall (12) of said fan housing (1), and
operable to rotate about a central axis (X) that is transverse to said top and bottom
walls (12, 11) of said fan housing (1); and
an air-guiding unit (3) mounted fixedly in said receiving space (10) in said fan housing
(1) and disposed adjacent to said air inlet (111) in said bottom wall (11) of said
fan housing (1) , said air-guiding unit (3) including a center connecting member (31)
disposed coaxially with the central axis (X), and a plurality of air-guiding blades
(32) angularly spaced apart from each other and interconnecting said central connecting
member (31) and said surrounding side wall (13) of said fan housing (1), an angular
distance (θ) between each adjacent pair of said air-guiding blades (32) being different from
that of any other adjacent pair of said air-guiding blades (32).
2. The fan device as claimed in Claim 1, characterized in that said air-guiding unit (3') further includes a plurality of auxiliary air-guiding
blades (33) extending inwardly and radially from said surrounding side wall (13) of
said fan housing (1) toward said central connecting member (31), each of said auxiliary
air-guiding blades (33) being disposed between a corresponding adjacent pair of said
air-guiding blades (32) and being spaced apart from the corresponding adjacent pair
of said air-guiding blades (32) and said central connecting member (31).
3. The fan device as claimed in Claim 2, further characterized in that said auxiliary air-guiding blades (33) of said air-guiding unit (3') have the same
length.
4. The fan device as claimed in Claim 2, further characterized in that each of said auxiliary air-guiding blades (33) of said air-guiding unit (3') has
a length different from that of any other one of said auxiliary air-guiding blades
(33).
5. The fan device as claimed in Claim 1,
characterized in that said fan impeller (2) includes:
a hub body (21) disposed coaxially with the central axis (X); and
a plurality of fan blades (22) extending outwardly and radially from said hub body
(21) and angularly spaced apart from each other, an angular distance (φ) between each adjacent pair of said fan blades (22) being different from that of
any other adjacent pair of said fan blades (22).