ELECTRIC BLIND

STORE ELECTRIQUE

English Abstract

An electric blind includes a frame, a plurality of
horizontal slat units, and a stepping motor. The frame
has two side vertical rods pivotally connected with the
slat units, and a linking rod is fixed with a lengthwise
side of all the slat units, possible to force the slat units
synchronously swing for an angle. The stepping motor
unit is composed of a stepping motor and a controller.
The stepping motor is positioned in a cavity of one of the
two side vertical rods, connected with a slat of the salt
units. Further the controller controls the rotating angle
of the motor, and the stepping motor can rotate idle in
case the motor should meet an exterior force (for
example, in case of the slat units already swung to the
largest angle), or the slat units are manually moved any
time. Thus the electric blind may not easily be broken or
damaged.

Claims

WHAT IS CLAIMED IS:
An electric blind comprising:
a frame having plural insert holes respectively in
two side vertical rods, said plural insert holes spaced
apart equidistantly, and a cavity formed in one of said
side vertical rods just behind one of said plural insert
holes;
a preset number of slat units, each slat unit having
a pin extending forward from two ends and fitting in one
of said insert holes of said frame;
a linking rod fixed vertical with one lengthwise
side of all said horizontal slat units, said linking rod
possible to move up and down together with all said slat
units when said slat unit is swung by a stepping motor
for an angle;
a stepping motor unit composed of said stepping
motor and a controller, said stepping motor positioned in
said cavity of said frame, said stepping motor connected
with said slat having said pin inserted in said cavity so
said slat unit may be swung by stepping said motor, said
controller controlling input signal fed in said stepping
motor.
2. The electric blind as claimed in Claim 1,
wherein at least one of said slat units has a slat with at
least one end fitted with an end cap, said slat has a
preset shape, said end cap is provided with a recessed
groove to fit with said end of said slat, and said end cap
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has a pin extending outward.
3. The electric blind as claimed in Claim 1,
wherein said controller is directly connected with said
motor.
4. The electric blind as claimed in Claim 1,
wherein said controller controls said motor by infrared
ray.
5. The electric blind as claimed in Claim 1,
wherein said controller controls operation of said motor
by pulse, and at the same time, the rotating angle of said
motor makes up a constant proportion with the number of
input pulse of said controller.
6. The electric blind as claimed in Claim 1,
wherein said motor is connected with said slat unit by
means of a linking member, which has two opposite sides
respectively provided with a position groove and an
insert groove lengthwise, said motor has a shaft
provided with a flat position surface to fit in said
position groove of said linking member, and said pin fits
in said insert groove.
7. The electric blind as claimed in Claim 1,
wherein a gear unit is pivotally provided between said
motor and said slat unit connected with said motor, said
motor connected with an input end of said gear unit, and
said pin of said slat unit is connected with an output of
said gear unit.
8. The electric blind as claimed in Claim 1,
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wherein a set switch is fixed between said motor and said
slat unit, consisting of a protruding wheel and an
electrical switch, said protruding wheel generates a
location signal in accordance to swinging of said slat
unit to said electrical switch, which then sends a related
signal to said controller so that said controller can reset
the location of said slat units.

Description

CA 02532092 2006-01-05
ELECTRIC BLIND
BACKGROUND OF THE INVENTION
Field of the Invention
This invention relates to an electric blind,
particularly to one provided with a stepping motor for
driving the slat units of a blind to let the slat units swing for a needed
angle.
Description of the Prior Art
A conventional blind shown in Fig. 1 includes a
frame 1 and a plurality of horizontal slats 2 pivotally
arranged in the frame 1, and all the horizontal slats 2 are
connected with a linking rod 3 so that all the slats 2 may
swing all synchronously, driven by a motor 4 installed in
an interior of the frame 1.
However, the slats of the conventional blind
cannot be adjusted in their angle to be swung, in spite
that the slats can be swung by the motor, only having two
angles, that is, one for opened and another for closed.
Moreover, in case that the slats receive an exterior force
and stopped immovable, the coil of the motor 4 may be
overloaded to burn up.
SUMAMRY OF THE INVENTION
The electric blind in the invention includes a
frame, a plurality of slat units, a linking ro'd, and a
stepping motor unit. The frame has two side vertical rods
pivotally connected with the horizontal slat units
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between, and the linking rod is fixed with a lengthwise
side of all the slat units, so all the slat units may
synchronously swing to an angle by the function of the
linking rod when the steeping motor rotates one of the
slat units, The stepping motor is positioned in one of the
two side vertical rods, connected with only one end of
one slat unit so that all the slat units may swing at the
same time by function of the linking rod.
In addition, the stepping motor is moved by input
pulse to generate a certain angle rotation and its angle
rotated is accurate owing to the input pulse controlling
its.extent of rotation, and at the same time the motor can
rotate idle in case of the input pulse interrupted by an
exterior force, Therefore, the slat units cannot be driven
temporarily by the stepping motor if the stepping motor
receives irregular resistance (such as when the slat units
swings to the utmost angle), or if the slat units are
pulled by a user any time, avoiding damage.
BRIEF DESCRIPTION OF DRAWINGS
This invention will be better understood by
referring to the accompany drawings, wherein:
Figure 1 is a perspective view of a conventional
electric blind;
Figure 2 is a perspective view of a preferred
embodiment of an electric blind in the present invention;
Figure 3 is a partial exploded perspective view of
the preferred embodiment of an electric blind in the
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present invention;
Figure 4 is an exploded perspective view of a slat
unit in the present invention;
Figure 5 is a perspective view of a stepping motor
to be combined with one slat unit in the present
invention; and,
Figure 6 is a side view of a second embodiment of
an electric blind with a stepping motor and a slat angle
sensor in the present invention.
DETAILED DESCRIPTION OF THE PREFERRED
EMBODIMENT
A preferred embodiment of an electric blind in the
present invention, as shown in Figs. 2 and 3, includes a
frame 10, a plurality of slat units 20, a linking rod 30
and a stepping motor unit 40 as main components,
The frame 10 is provided with a plurality of insert
holes 11 spaced apart equidistantly in two side vertical
rods respectively, and a cavity 12 just behind one of the
insert groove 11 in one of the two vertical rods. The
insert holes 11 in one side vertical rod are respectively
at the same level with those 11 in the other side vertical
rod to align to each o.ther.
Each slat unit 20 as shown in Fig. 4, consists of a
slat 21 and two end caps 22 with a recessed hollow 221 to
fit around one of the two ends of the slat 21. Further, a
pin 222 is fixed with in a center of an outer side of the
end cap 22 to fit in the insert hole 11 of the side vertical
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rod of the frame so that each slat 21 may be combined
pivotally and horizontally with the frame.
The connect rod 30 is fixed vertically with an
lengthwise side of all the horizontal slats 21 so that all
the slat units 20 may rotated for a certain angle at the
same time by the interactive function of the connect rod
30, when they are driven by the stepping motor unit 40.
The stepping motor unit 40 consists of a stepping
motor 41 and a controller 42, and the stepping motor 41
is positioned in the cavity 12 of the frame 10 and has a
shaft 411, which is provided with a flat position surface
412 on its end. Further a linking member 43 fits around
the flat position surface 412 of the shaft 411, having a
position groove 431 and a fit groove 432 respectively in
two ends. Then the shaft 411 of the stepping motor 41
fits in the position groove 431 of the linking member 43,
and one of the slat unit 20 fits in the fit groove 432 of
the linking member 43 so that the stepping motor unit 40
may drive all the slats units 20 through the connect rod
20 for changing the angle of the slat units 20. As to the
controller 42, it is connected with the rear side of the
motor 41, controlling the input pulse of the steppi-ng
motor 41 by means of infrared ray,
Next, how to use the electric blind in the invention
is to be described as follows. Referring to Figs. 3, 4 and
5, the electric blind has the slat units,20 possible to be
handled to manually change the angle of the slat units 20,
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and also at the same time possible to be electrically
handled to change the angle of the slat units 20. In case
of electrically changing the angle of the slat units 20 of
this blind, the controller can control the input pulse to
the stepping motor 41 so the shaft 411 of the stepping
motor 41 may be rotated to a needed angle. Thus the
electric blind is changed in its angle by the controller 42,
which controls the input pulse to the stepping motor 41
and adjusts the rotating angle of the motor 41 so as to
make the slat units 20 rotate for , a needed angle.
Provided that the slat units 20 should be interrupted by
an external force and become stopped, the input pulse to
the motor 41 might not force the stepping motor 41
overloaded, enabling the slat units 20 still be swung for
a needed, angle whether the stepping motor 41 rotates or
not, because the stepping motor 41 can rotate idle in the
worst case.
In addition, it is worth mentioning th.at the slat
units 20 can have a movement to return to a zero point so
the controller or manual operation can swing the slat
units 20 to the zero point. In other words, the stepping
motor 41 can rotate idle if the slat units 20 is swung to
the utmost-point, and if the stepping motor 41 keeps on
rotating for a preset time, the slat units 20 can be shut
completely (i.e., move to the zero point). And
subsequently if the motor starts from the zero point, the
slat units 20 are to be swung precisely to the needed
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angle according to the input pulse.
Next, Fig. 6 shows a second preferred embodiment
of an electric blind in the invention, which has the same
structure as the first one, except that a gear unit is
added between the motor 41 and the linking member 43.
The gear unit consists of a gear unit 433 and a set switch
44. The gear unit 433 can be a bevel gear unit. The set
switch 44 is composed of a protruding wheel 441 and an
electrical switch 442, and the protruding wheel can fit
around the linking member 43 or firmly connected with
the slat 21, the end cap 22 or the pin 222. Then when the
slat 21 reaches the zero point, it touches the electrical
switch 44.2, which then generates a signal, and the
controller 42 receives the signal of the zero point from
the slat unit 20. Besides, the number of the combination
of the protruding wheel 441 and the electrical switch 442
can be increased, augmenting the number of sensing
points. For example, more accurate and timely control
can be got by eight different locations that three sensing
points in conjunction with a two digit code mode can
obtain. It goes without saying that the sensing signal can
be substituted by a photo-sensing mode, which is a
well-known art not to be described here.
Lastly, the invention has the following advantages,
as can be seen from the foresaid description.
The sfat units can be manually rotated even if the
stepping motor is still in operation, and then the
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stepping motor can rotates idle. Therefore, the angle of
the slat units can be adjusted, not making any damage to
the stepping motor, with its service life prolonged.
The control signal for the motor is pulse, so the
rotating process for an angle of the slat units is in
proportion to the number of the pulse. It means that the
angle of the slat units can be accurately calculated by
the number of the input pulse, so the stepping motor can
make a preset angle rotation owing to the function of the
controller, with its practicality and accuracy of the
control increased.
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.
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Representative Drawing