Abstract
A swaying device for an electric fan includes a base consisting of
an upper shell and a lower shell, a small motor and a detective element
arranged in the base. The motor turns 360 degrees or sways for a certain
angle adjustable to move the upper shell in the same way to turn or
sway an electric fan fixed on the upper shell in the same way of the
upper shell. The detecting element finds out the swaying angle of
the electric fan and the speed of the swaying.
Claims
1. A swaying device for an electric fan comprising: a base consisting
of an upper shell and a lower shell, said upper shell having a bottom
wall and a vertical annular wall, a non-circular shaft provided to
extend down from a lower surface of the bottom wall of said upper
shell, a rod hole formed in said non-circular shaft; said lower shell
having a con-circular hole formed in the center vertical portion for
said con-circular shaft of said upper shell to fit immovably therein:
a small motor fixed on the bottom of said upper shell to turn or sway
together with said motor, and an eccentric rod fixed eccentrically
under a bottom surface of said motor and extending down to fit in
said rod hole of said non-circular shaft of said upper shell, said
motor turning around for 360 degrees or swaying for a certain angle
adjustable back and forth with its spindle as a shaft when electrically
powered so that said upper shell may also turn around for 360 degrees
or swaying for a certain angle back and forth to result in that an
electric fan fixed on said upper shell of said base may also turn
around for 360 degrees or sway for a certain angle back and forth
together with said upper shell of said base: and, a detecting element
fixed under the bottom of said upper shell of said base for detecting
the swaying angle of the electric fan fixed on said upper shell of
said base.
1. The swaying device for an electric fan as claimed in claim 1,
wherein said detecting element is a light detecting one.
2. The swaying device for an electric fan as claimed in claim 1,
wherein said detecting element is a Hall IC, which reacts with one
of the plural magnetic members for sensing the swaying angle of
the electric fan.
Description
FIELD OF THE INVENTION
[0001] The invention relates to a swaying device for an electric
fan, particularly having a small motor arranged in a base to specifically
move an upper shell of a base to turn 360 degrees or sway for a
certain angle so an electric fan fixed on the upper shell may turn
or sway in the same certain angle at the same time, and a detective
element for finding out the swaying angle and the speed of the swaying.
BACKGROUND OF THE INVENTION
[0002] A conventional swaying device for an electric fan shown
in FIGS. 1, 2, 3 and 4 includes a speed reducer (A), a plurality
of gears (A0) engaging with the speed reducer (A) one another. The
rotation of the gears (A0) are controlled by a synchronous stator
(B), which has no brush and a coil (B3), which is electrically powered
to generates a magnetic field for rotating a rotor (B0), The rotor
(B0) has a spindle (B1) connected with a gear (B2) engaging with
the gear (A0) of the speed reducer (A) for the fan head (that is
the fan together the motor and related components) to sway for a
certain angle back and forth. However, The synchronous stator has
no brush, so the rotating direction of the rotor (B0) and the magnetic
field are not constant. Therefore, the swaying of the fan head is
impossible to be smoothly controlled. In other words, the fan head
is liable to be moved reversely by an exterior force. So a cooling
fan available on the market as shown in FIG. 3 may have its fan
C easily reversely sway by tough of a finger or something else.
On this ground, a traditional electric fan may be provided with
a control rod (D) shown in FIG. 4 for enforcing the fan head to
sway in the correct swaying angle.
[0003] Moreover, the swaying angle controlled by the control rod
(D) of the traditional electric fan is set constant, impossible
to adjust, in the value of 30-45 degrees rightward and leftward.
SUMMARY OF THE INVENTION
[0004] The invention has been devised to offer a swaying device
for an electric fan, possible to force the electric fan to turn
for 360 degrees or sway for a certain angle adjustable and its swaying
angle and speed is accurately detectable.
[0005] The feature of the invention is described as follows.
[0006] 1. The swaying device for an electric fan in the invention
has a base and a small motor arranged in the base for turning for
360 degrees or swaying for a certain angle adjustable an electric
fan fixed on an upper shell of the base and at the same time, and
the swaying angle and speed can be detected by a detecting element
in the base.
[0007] 2. The detecting element in the base is a magnetic component
or a Hall IC.
[0008] 3. The detecting element in the base may be a light sensing
component or an infrared sensing component.
BRIEF DESCRIPTION OF DRAWINGS
[0009] This invention will be better understood by referring to
the accompanying drawings, wherein:
[0010] FIG. 1 is a front view of a conventional speed reducer used
in an electric fan;
[0011] FIG. 2 is a cross-sectional view of FIG. 1;
[0012] FIG. 3 is a front view of a conventional cooling fan;
[0013] FIG. 4 is a side view of a conventional electric fan;
[0014] FIG. 5 is an exploded perspective view of a first embodiment
of a swaying device for an electric fan in the present invention;
[0015] FIG. 6 is a cross-sectional view of the first embodiment
of a swaying device for an electric fan in the present invention;
[0016] FIG. 7 is a magnified view of the part marked (A) in FIG.
6;
[0017] FIG. 8 is a side cross-sectional view of a second embodiment
of a swaying device for an electric fan in the present invention;
and,
[0018] FIG. 9 is a magnified view of the part marked (B) in FIG.
8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] A first embodiment of a swaying device for an electric fan
is to be fixed at any location of a housing 10 of an electric fan,
including, as shown in FIGS. 5, 6 and 7, a base 2, a small motor
22, a light detecting element 23 and two conductors 24 and a disk
25 as main components.
[0020] The base 2 consists of an upper shell 20 of preferably a
cylindrical shape and a lower shell 21 of a similar shape as the
upper shell 20.
[0021] The small motor 22 is arranged stably in the base 2 on the
upper shell 20, having an eccentric rod 220 positioned eccentrically
on a lower surface of the motor housing and extending in a rod hole
222 of a non-circular shaft 221 (shown as hexagonal in the Figures),
which extends down from the bottom surface of the upper shell 20.
The non-circular shaft 221 also extends immovably in a non-circular
shaft hole 210 of the lower shell 21. So when the motor 22 is powered,
the eccentric rod 220 cannot rotate, because it is fixed with the
con-circular shaft 221 fitted immovably in the non-circular hole
210 of the lower shell 21. Therefore, the whole motor 22 is forced
to turn around its spindle and also forcing the upper shell 20 to
turn at the same time, with its spindle stopped rotating. Thus,
an electric fan fixed on the upper shell 20 may wholly turn for
360 degrees or sway for a certain angle adjustable back and forth
together with the upper shell 20, controlled by a separate device.
[0022] The light-detecting element 23 is fixed under the bottom
surface of the upper shell 20, and two conductors 24 are fixed on
the upper bottom surface of the upper shell 20.
[0023] The lower shell 21 is provided with the non-circular hole
210 for the non-circular shaft 221 to fit therein and plural holes
211 for fixing a disk 25 on the lower shell 21 and under the upper
shell 20.
[0024] The disk 25 fixed immovable on the lower shell 21 is provided
with two annular conductive rings 250 spaced apart with an annular
gap on an upper surface, but semicircular curves can also be used
instead of the annular rings 250. The conductive rings 250 contact
with the two conductors 24 for supplying the motor 22 with electric
power. Further, a plurality of stop members 251 for the light detective
element 23 to react for detecting the swaying angle and its speed.
A separate device not covered in this invention adjusts the turning
for 360 degrees or swaying for a certain angle of the small motor
22.
[0025] Next, when the motor 22 turns for 360 degrees or sways for
a certain angle, it moves the upper shell 20 in the same way, so
an electric fan fixed on the upper shell 20 of the base 2 also turns
or sways in the same way as the small motor 22. Moreover, the light-detecting
element 23 may face in turning or swaying one of the stop members
251 for the light-detecting element 23 to react and operate to sense
the swaying angle and its speed of the electric fan. The light detecting
element 23 can also be positioned on the disk 25, with the stop
members 25 fixed on the upper shell 20, obtaining the same function
as the way just described.
[0026] Further, FIGS. 8 and 9 shows a second embodiment of a swaying
device for an electric fan in the invention, in which a Hall IC
23A is used as a detecting element, and plural magnetic elements
251A is fixed on the disk 25. Then the Hall IC 23A reacts with one
of the magnetic elements 251A to find out the swaying angle of the
electric fan swayed by the upper shell 20, which is swayed by the
motor 22.
[0027] While the preferred embodiments of the invention have been
described above, it will be recognized and understood that various
modifications may be made therein and the appended claims are intended
to cover all such modifications that may fall within the spirit
and scope of the invention. |