U.S. patent application number 11/331312 was filed with the patent office on 2006-12-07 for electric fan.
Invention is credited to Chung-Yin Cheng.
Application Number | 20060276122 11/331312 |
Document ID | / |
Family ID | 37494756 |
Filed Date | 2006-12-07 |
United States Patent
Application |
20060276122 |
Kind Code |
A1 |
Cheng; Chung-Yin |
December 7, 2006 |
Electric fan
Abstract
An electric fan includes a motor, two blade units, and two
engaging units. The motor has a motor shaft that defines an axis
and that has two axially opposite end segments. Each of the end
segments has an engaging region. The engaging regions of the end
segments are disposed at angularly opposite positions relative to
the axis. Each of the blade units includes a hub that is sleeved on
a respective one of the end segments. Each of the engaging units
includes a first engaging member provided on the engaging region of
a respective one of the end segments, and a second engaging member
provided on the hub of a respective one of the blade units and
engaging the first engaging member.
Inventors: |
Cheng; Chung-Yin; (Chang-Hua
Hsien, TW) |
Correspondence
Address: |
OSTROLENK FABER GERB & SOFFEN
1180 AVENUE OF THE AMERICAS
NEW YORK
NY
100368403
US
|
Family ID: |
37494756 |
Appl. No.: |
11/331312 |
Filed: |
January 11, 2006 |
Current U.S.
Class: |
454/254 |
Current CPC
Class: |
F04D 29/263 20130101;
F04D 25/08 20130101; F04D 25/166 20130101; F24F 7/007 20130101 |
Class at
Publication: |
454/254 |
International
Class: |
F24F 7/00 20060101
F24F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 6, 2005 |
TW |
094118548 |
Claims
1. An electric fan comprising: a motor with a motor shaft defining
an axis and having two end segments that are axially opposite to
each other, each of said end segments having an engaging region,
said engaging regions of said end segments being disposed at
angularly opposite positions relative to said axis; a pair of blade
units coupled respectively to and driven by said end segments of
said motor shaft, each of said blade units including a hub that is
sleeved on the respective one of said end segments, and a plurality
of blades that extend from said hub; and a pair of engaging units,
each of which includes a first engaging member that is provided on
said engaging region of a respective one of said end segments of
said motor shaft, and a second engaging member that is provided on
said hub of a respective one of said blade units and that engages
said first engaging member, thereby securing said blade units to
said end segments of said motor shaft, respectively.
2. The electric fan as claimed in claim 1, wherein each of said end
segments of said motor shaft has a free end portion with a
non-circular cross-section, said free end portion of each of said
end segments having a flat surface that defines said first engaging
member of the respective one of said engaging units, said hub of
each of said blade units including a sleeve part that is sleeved on
the respective one of said end segments and that has a free end
portion with a non-circular cross-section, said free end portion of
said sleeve part of said hub of each of said blade units having a
flat surface that defines said second engaging member and that
conforms to and that contacts said flat surface of said free end
portion of the respective one of said end segments of said motor
shaft.
3. The electric fan as claimed in claim 1, wherein each of said end
segments of said motor shaft is formed with an engaging hole that
defines said first engaging member of the respective one of said
engaging units, said hub of each of said blade units including a
sleeve part that is sleeved on the respective one of said end
segments and that is formed with a threaded hole, said second
engaging member of each of said engaging units being in the form of
a screw that engages threadedly and that extends through said
threaded hole in said sleeve part of said hub of the respective one
of said blade units and that engages said engaging hole in the
respective one of said end segments.
4. The electric fan as claimed in claim 1, wherein each of said end
segments of said motor shaft is formed with an engaging protrusion
that defines said first engaging member of the respective one of
said engaging units, said hub of each of said blade units including
a sleeve part that is sleeved on the respective one of said end
segments and that has a free end portion formed with an engaging
groove which extends axially, which opens in a direction toward
said motor, and which defines said second engaging member of the
respective one of said engaging units, said engaging protrusion of
each of said end segments extending through said engaging groove in
said free end portion of said sleeve part of said hub of the
respective one of said blade units.
5. The electric fan as claimed in claim 2, wherein said hub of each
of said blade units further includes a hub base and an outer
annular wall that extends axially from a periphery of said hub base
and that surrounds said sleeve part, said hub base having an inner
side and an outer side that is opposite to said inner side, said
sleeve part of said hub of each of said blade units further having
an open outer end that is opposite to said free end portion of said
sleeve part, each of said end segments of said motor shaft having a
threaded portion that extends axially and outwardly through said
open outer end of said sleeve part of said hub of the respective
one of said blade units, said electric fan further comprising a
pair of screw nuts, each of which is disposed at said outer side of
said hub base of a respective one of said blade units and each of
which engages threadedly said threaded portion of a respective one
of said end segments of said motor shaft.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority of Taiwanese application
no. 094118548, filed on Jun. 6, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to an electric fan, more particularly
to an electric fan with a pair of blade units.
[0004] 2. Description of the Related Art
[0005] Referring to FIG. 1, a conventional electric fan is shown to
include a motor 1, a pair of blade units 2 respectively driven by
the motor 1, and a stand unit 3 for supporting a bottom of the
motor 1. When the motor 1 is actuated, the blade units 2 rotate
simultaneously so as to generate two streams of air flow blowing in
opposite directions relative to an axis so as to dissipate
heat.
[0006] Although the aforesaid electric fan is able to dissipate
heat effectively, since only one motor 1 is used to simultaneously
drive the two blade units 2, vibration tends to occur during
rotation of the blade units 2 when the blade units 2 mounted on two
end portions of a motor axle 101 of the motor 1 are unbalanced.
SUMMARY OF THE INVENTION
[0007] Therefore, the object of the present invention is to provide
an electric fan that is capable of overcoming the aforesaid
drawback of the prior art.
[0008] Accordingly, an electric fan of this invention comprises a
motor, a pair of blade units, and a pair of engaging units.
[0009] The motor has a motor shaft that defines an axis and that
has two end segments which are axially opposite to each other. Each
of the end segments has an engaging region. The engaging regions of
the end segments of the motor shaft are disposed at angularly
opposite positions relative to the axis.
[0010] The blade units are coupled respectively to and are driven
by the end segments of the motor shaft. Each of the blade units
includes a hub that is sleeved on the respective one of the end
segments, and a plurality of blades that extend from the hub.
[0011] Each of the engaging units includes a first engaging member
that is provided on the engaging region of a respective one of the
end segments of the motor shaft, and a second engaging member that
is provided on the hub of a respective one of the blade units and
that engages the first engaging member, thereby securing the blade
units to the end segments of the motor shaft, respectively.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] 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:
[0013] FIG. 1 is a fragmentary partly sectional view of a
conventional electric fan;
[0014] FIG. 2 is a fragmentary partly sectional view of the first
preferred embodiment of an electric fan according to the present
invention;
[0015] FIG. 3 is an exploded partly sectional view of an assembly
of a motor and a pair of blade units of the first preferred
embodiment;
[0016] FIG. 4 is a sectional view taken along the line IV-IV in
FIG. 2;
[0017] FIG. 5 is an exploded partly sectional view of the second
preferred embodiment of an electric fan according to the present
invention;
[0018] FIG. 6 is a fragmentary assembled partly sectional view of
the second preferred embodiment;
[0019] FIG. 7 is a sectional view taken along the line VII-VII in
FIG. 6;
[0020] FIG. 8 is an exploded partly sectional view of the third
preferred embodiment of an electric fan according to the present
invention;
[0021] FIG. 9 is a fragmentary assembled partly sectional view of
the third preferred embodiment; and
[0022] FIG. 10 is a sectional view taken along the line X-X in FIG.
9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] Before the present invention is described in greater detail
with reference to the accompanying preferred embodiments, it should
be noted herein that like elements are denoted by the same
reference numerals throughout the disclosure.
[0024] Referring to FIGS. 2 to 4, the first preferred embodiment of
an electric fan according to the present invention is shown to
include a motor 10, a pair of blade units 20, and a pair of
engaging units 50. The first preferred embodiment further includes
a stand unit 40 for supporting the motor 10. The stand unit 40
includes a connecting rod 41 coupled to a bottom of the motor 10,
and a stand 42 connected to the connecting rod 41.
[0025] The motor 10 has a motor shaft 11 that defines an axis (L)
and that has two end segments 111 axially opposite to each other.
Each of the end segments 111 has an engaging region 113. The
engaging regions 113 of the end segments 111 of the motor shaft 11
are disposed at angularly opposite positions relative to the axis
(L).
[0026] The blade units 20 are coupled respectively to and are
driven by the end segments 111 of the motor shaft 11. Each of the
blade units 20 includes a hub 21 that is sleeved on a respective
one of the end segments 111, and a plurality of blades 22 that
extend from the hub 21.
[0027] Each of the engaging units 50 includes a first engaging
member 51 that is provided on the engaging region 113 of a
respective one of the end segments 111 of the motor shaft 11, and a
second engaging member 52 that is provided on the hub 21 of a
respective one of the blade units 20 and that engages the first
engaging member 51, thereby securing the blade units 20 to the end
segments 111 of the motor shaft 11, respectively.
[0028] In the first embodiment, each of the end segments 111 of the
motor shaft 11 has a free end portion 112 with a non-circular
cross-section. The free end portion 112 of each of the end segments
111 has a flat surface 116 that is disposed at the engaging region
113 and that defines the first engaging member 51 of the respective
one of the engaging units 50. The hub 21 of each of the blade units
20 includes a sleeve part 212 that is sleeved on the respective one
of the end segments 111 and that has a free end portion 213 with a
non-circular cross-section. The free end portion 213 of the sleeve
part 212 of the hub 21 of each of the blade units 20 has a flat
surface 216 that defines the second engaging member 52 and that
conforms to and that contacts the flat surface 116 of the free end
portion 112 of the respective one of the end segments 111 of the
motor shaft 11. Moreover, the hub 21 of each of the blade units 20
further includes a hub base 210 and an outer annular wall 214 that
extends axially from a periphery of the hub base 210 and that
surrounds the sleeve part 212, which extends axially from an inner
portion of the hub base 210. The hub base 210 has an inner side
2101 and an outer side 2102 that is opposite to the inner side
2101. The sleeve part 212 of the hub 21 of each of the blade units
20 further has an open outer end 211 that is opposite to the free
end portion 213 of the sleeve part 212. Each of the end segments 11
of the motor shaft 11 has a threaded portion 114 that extends
axially and outwardly through the open outer end 211 of the sleeve
part 212 of the hub 21 of the respective blade unit 20. The
electric fan further comprises a pair of screw nuts 30, each of
which is disposed at the outer side 2102 of the hub base 210 of a
respective blade unit 20 and each of which engages threadedly the
threaded portion 114 of a respective one of the end segments 111 of
the motor shaft 11 so as to secure the blade units 20 to the end
segments 111 of the motor shaft 11 after engagement between the
first and second engaging members 51, 52 of the engaging units
50.
[0029] After assembly, since the engaging units 50 are disposed at
angularly opposite positions relative to the axis (L), balance
between the blade units 20 mounted respectively on the end segments
111 of the motor shaft 11 can be achieved, and vibration during
actuation of the motor 10 can be reduced significantly.
[0030] Referring to FIGS. 5, 6 and 7, the second preferred
embodiment of this invention differs from the first preferred
embodiment in that: each of the end segments 111 of the motor shaft
11 is formed with an engaging hole 116 that is disposed in the
engaging region 113 and that defines the first engaging member 51
of the respective one of the engaging units 50. The sleeve part 212
of the hub 21 of each blade unit 20 is formed with a threaded hole
215. The second engaging member 52 of each of the engaging units 50
is in the form of a screw 30 that engages threadedly and that
extends through the threaded hole 215 in the sleeve part 212 of the
hub 21 of the respective one of the blade units 20 and that engages
the engaging hole 116 in the respective one of the end segments 111
so as to secure the blade units 20 to the end segments 111 of the
motor shaft 11 after engagement between the first and second
engaging members 51, 52 of the engaging units 50. Moreover, the
sleeve part 212 of the hub 21 of each of the blade units 20 is
formed with a blind hole 217 for insertion of the respective one of
the end segments 111 of the motor shaft 11
[0031] Referring to FIGS. 8 to 10, the third preferred embodiment
of this invention differs from the first preferred embodiment in
that: the engaging region 113 of each end segment 111 is formed
with at least one engaging protrusion 116 (in this embodiment, two
engaging protrusions 116 are formed on the engaging region 113)
that defines the first engaging member 51 of the respective one of
the engaging units 50. The sleeve part 212 of the hub 21 of each
blade unit 20 has a free end portion 213 formed with an engaging
groove 215 (in this embodiment, two engaging grooves 215 are formed
in the free end portion 213 of the sleeve part 212) which extends
axially, which opens in a direction toward the motor 10, and which
defines the second engaging member 52 of the respective one of the
engaging units 50. Each engaging protrusion 116 of each of the end
segments 111 extends into the corresponding engaging groove 215 in
the free end portion 213 of the sleeve part 212 of the hub 21 of
the respective one of the blade units 20, as best shown in FIG. 10,
thereby securing the blade units 20 to the end segments 111 of the
motor shaft 11.
[0032] By disposing the engaging units 50 at the angularly opposite
positions relative to the axis (L), the aforesaid drawback
associated with the prior art can be alleviated.
[0033] While the present invention has been described in connection
with what is considered the most practical and preferred
embodiments, it is understood that this invention is not limited to
the disclosed embodiments but is intended to cover various
arrangements included within the spirit and scope of the broadest
interpretation so as to encompass all such modifications and
equivalent arrangements.
* * * * *