Note: Descriptions are shown in the official language in which they were submitted.
CA 02568487 2006-11-22
WINDING MECHANISM OF BLIND
BACKGROUND OF THE INVENTION
Field of Invention
The present invention relates to blinds and more particularly to a winding
mechanism of a blind (e.g., roll-up or Venetian blind) which can be releasably
locked
in any one of a plurality of positions relative to a top of window frame.
Related Art
Typically, a blind (e.g., roll-up or Venetian blind) is adapted to raise or
lower by
pulling a lift cord coupled to a winding mechanism. However, it is possible
that a child
may tie the exposed cord about the neck to cause danger or even death. Thus,
this is
not safe.
A conventional roll-up blind having a hidden lift cord is shown in FIG. 1 and
comprises a head rail 1 fixed to a top of window frame, two spaced, opposite
springs 2
in the head rail 1, a bottom stiffener strip 3, a plurality of folds 4 coupled
between the
head rail 1 and the stiffener strip 3, each fold 4 having two openings
proximate both
sides, two side rails 5 and 6 of U-section fixed at both sides of the window
frame, the
side rails 5 and 6 adapted to allow both ends of the folds 4 to longitudinally
slide
therein, and two cords 7 and 8 in which the cord 7 has one end passed the left
openings to couple to one spring 2 and the other end tied off at the left side
rail 5, and
the cord 8 has one end passed the right openings to couple to the other spring
2 and
the other end tied off at the right side rail 6.
However, the previous design suffered from several disadvantages. For example,
the springs 2 tend to lose its elasticity after a predetermined times of
lowering or
raising operation of the folds 4. And in turn, it may compromise the
positioning
capability of folds 4 by operating the cords 7 and 8. Further, there are no
guide
members for the cords 7 and 8 in the head rail 1 and the stiffener strip 3. It
may
increase friction in pulling the cords 7 and 8 during operation. To the worse,
the cords
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7 and 8 may break after a predetermined times of lowering or raising
operation.
Furthermore, the stiffener strip 3 is relatively thin, resulting in a poor
maneuverability of the blind.
Thus, it is desirable to provide an improved winding mechanism of blind in
order to overcome the above drawbacks of prior art.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a winding mechanism
mountable at a groove of a head rail of a blind, the blind further including a
bottom
stiffener strip and a sheet of drapery material coupled between the head rail
and
the stiffener strip, comprising:
a cord reel provided on the head rail;
lines each having one end tied off at a first position of the stiffener strip,
passed one side of the sheet of drapery material, the head rail, and the other
side
of the sheet of drapery material, and having the other end tied off at a
second
position of the stiffener strip, the other end of the line formed as a bight
section
proximate the cord reel;
a cord wound around the cord reel and having at least one loop wrapped
around the bight section;
a first drum rotated with the cord reel;
a second drum;
a tape spring interconnected the first drum and the second drum, the spring
including two worm sections together formed an S, the spring adapted to exert
a
force to support the weight of the sheet of drapery material; and
a plurality of spaced guide rollers disposed in the groove and holes formed
on a bottom of the groove, the guide rollers being coupled together by winding
the
cord therearound, two ends of the cord being adapted to pass the holes;
wherein in a downward pulling of the stiffener strip the cord reel rotates to
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release the lines and the cord for lowering the sheet of drapery material with
one
worm section being further wound and the other worm section being loosened as
a
counterweight of the sheet of drapery material so as to reach a balance,
thereby
maintaining the sheet of drapery material at any one of a plurality of
positions from
a fully raised position to a fully lowered position in response to stopping
the cord
reel; and in an upward pulling of the stiffener strip the cord reel rotates in
an
opposite direction to wind the lines and the cord for lifting the sheet of
drapery
material with one worm section being loosened and the other worm section being
further wound as a counterweight of the sheet of drapery material so as to
reach a
balance, thereby maintaining the sheet of drapery material at any one of a
plurality
of positions from the fully raised position to the fully lowered position in
response to
stopping the cord reel.
Preferably, it is therefore an object of the present invention to provide a
winding mechanism mountable at a groove of a head rail of a blind, the blind
further
including a bottom stiffener strip and a sheet of drapery material coupled
between
the head rail and the stiffener strip, comprising a cord reel provided on the
head
rail; a line having one end tied off at a first position of the stiffener
strip, passed one
side of the sheet of drapery material, the head rail, and the other side of
the sheet
of drapery material, and having the other end tied off at a second position of
the
stiffener strip, the other end of the line formed as a bight section proximate
the cord
reel; a cord wound around the cord reel and coupled to the bight section of
the line;
a first drum rotated with the cord reel; a second drum; a tape spring
interconnected
the first drum and the second drum, the spring including two worm sections
together formed an S, the spring adapted to exert a force to support the
weight of
the sheet of drapery material wherein in a downward pulling of the stiffener
strip the
cord reel rotates to release the line and the cord for lowering the sheet of
drapery
material with one worm section being further wound and the other worm section
being loosened as a counterweight of the sheet of drapery material so as to
reach a
balance, thereby maintaining the sheet of drapery material at any one of a
plurality
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of positions from a fully raised position to a fully lowered position in
response to
stopping the cord reel; and a retaining member including an elongate seat
engaged
with a bottom surface of the stiffener strip, and two upwardly curved snapping
edges along front end rear edges of the seat for clamping the stiffener strip;
wherein in an upward pulling of the stiffener strip the cord reel rotates in
an
opposite direction to wind the line and the cord for lifting the sheet of
drapery
material with one worm section being loosened and the other worm section being
further wound as a counterweight of the sheet of drapery material so as to
reach a
balance, thereby maintaining the sheet of drapery material at any one of a
plurality
of positions from the fully raised position to the fully lowered position in
response to
stopping the cord reel.
Preferably, it is another object of the present invention to provide a winding
mechanism mountable at a groove of a head rail of a blind, the blind further
including a bottom stiffener strip and a sheet of drapery material coupled
between
the head rail and the stiffener strip, comprising a cord reel provided on the
head
rail; lines each having one end tied off at a first position of the stiffener
strip, passed
one side of the sheet of drapery material, the head rail, and the other side
of the
sheet of drapery material, and having the other end tied off at a second
position of
the stiffener strip, the other end of the line formed as a bight section
proximate the
cord reel; a cord wound around the cord reel and having at least one loop
wrapped
around the bight section; a first drum rotated with the cord reel; a second
drum; and
a tape spring interconnected the first drum and the second drum, the spring
including two worm sections together formed an S, the spring adapted to exert
a
force to support the weight of the sheet of drapery material; wherein in a
downward
pulling of the stiffener strip the cord reel rotates to release the lines and
the cord for
lowering the sheet of drapery material with one worm section being further
wound
and the other worm section being loosened as a counterweight of the sheet of
drapery material so as to reach a balance, thereby maintaining the sheet of
drapery
material at any one of a plurality of positions from a fully raised position
to a fully
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lowered position in response to stopping the cord reel; and in an upward
pulling of
the stiffener strip the cord reel rotates in an opposite direction to wind the
lines and
the cord for lifting the sheet of drapery material with one worm section being
loosened and the other worm section being further wound as a counterweight of
the
sheet of drapery material so as to reach a balance, thereby
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maintaining the sheet of drapery material at any one of a plurality of
positions from the
fully raised position to the fully lowered position in response to stopping
the cord reel.
The above and other objects, features and advantages of the present invention
will become apparent from the following detailed description taken with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a conventional roll-up blind;
FIG. 2 is an exploded view of a first preferred embodiment of winding
mechanism
to be mounted on a roll-up blind according to the invention;
FIG_ 3 is a perspective view of the assembled winding mechanism and blind of
FIG. 2;
FIG. 4 is a top view in part section of the winding mechanism;
FIG. 5 is a greatly enlarged, exploded view of the winding mechanism;
FIGS. 6 and 7 are transverse and longitudinal sectional views of the winding
mechanism respectively;
FIG. 8 is a perspective view of a second preferred embodiment of winding
mechanism for roll-up blind according to the invention;
FIG. 9 is a transverse sectional view of the winding mechanism shown in FIG.
8;
FIG. 10 is a longitudinal sectional view of the winding mechanism shown in
FIG. 8
where the winding mechanism is activating to lift the blind and a single loop
is
interconnected the joining point of the line and the cord reel;
FIG. 11 is a view similar to FIG. 10 showing another configuration thereof
where
loops are interconnected the joining point of the line and the cord reel;
FOG. 12 is a perspective view of the fully lifted blind according to the
invention;
FIG. 13 is a longitudinal sectional view of a third preferred embodiment of
winding
mechanism for roll-up blind according to the invention;
FIG. 14 is a transverse sectional view of the winding mechanism shown in FIG.
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13;
FIG. 15 is a longitudinal sectional view of a fourth preferred embodiment of
winding mechanism for roll-up blind according to the invention; and
FIG. 16 is a transverse sectional view of the winding mechanism shown in FIG.
15.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 2, 3 and 4, there is shown a winding mechanism 40 in
accordance with a first preferred embodiment of the invention. The winding
mechanism 40 is to be mounted on a roll-up blind comprising a head rail 10 of
U-section, a bottom stiffener strip 20, and a sheet of drapery material 30
coupled
between the head rail 10 and the stiffener strip 20 and comprised of a
plurality of folds
31 each having two orifices 32 proximate both sides. A plurality of spaced
guide rollers
11, 12, 14, and 15 and the winding mechanism 40 are disposed in a groove of
the
head rail 10. The guide rollers 11, 12, 14, and 15 are coupled together by a
continuous
line 49 wound around them. Two ends of the line 49 pass two bottom apertures
(not
shown) and the orifices 32 to tie off in the stiffener strip 20. The guide
rollers 11, 12, 14,
and 15 are adapted to guide the line 49 in its pulling operation (i.e., more
smooth).
Note that the sheet of drapery material 30 and its folds 31 of the roll-up
blind in this
embodiment can be replaced by slats of a Venetian blind in the other
embodiment.
Referring to FIGS. 5 to 7, the winding mechanism 40 comprises a case 41 open
to its bottom, the case 41 having an internal space 42 for mounting a cord
reel 43, a
first drum 44, and a second drum 45 therein. The winding mechanism 40 further
comprises at least three shafts 46 each having two ends fixed on two opposite
walls of
the case 41 with the cord reel 43, the first drum 44, or the second drum 45
rotatably
put thereon. A tape spring 47 is interconnected the first drum 44 and the
second drum
45. The tape spring 47 comprises two worm sections 471 and 472 together formed
an
S. The tape spring 47 can exert a force to support the weight of the sheet of
drapery
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material 30. A free end 48 of the worm section 472 is fixed on the first drum
44. A long
cord 13A is wound around the cord reel 43. A winding direction of the cord 13A
is the
same as that of each of the worm sections 471 and 472. One end of the cord 13A
passes one of two slits 411 on one side surface of the case 41 to couple to
the line 49
at a bight section 491 formed at the other end of the line 49. As such, the
line 49 and
the cord 13A can operate as a whole. The cord reel 43 comprises a gear 412 at
one
end to be meshed with a gear 413 of the first drum 44 such that the cord reel
43 and
the first drum 44 can rotate in opposite directions.
The S-shaped tape spring 47 is energized due to the same winding direction of
the vvorm sections 471 and 472 and the weight of the sheet of drapery material
30. A
downward pulling of the stiffener strip 20 by the hand together with the
weight of the
sheet of drapery material 30 can overcome an upward pulling force of the cord
13A
provided by the tape spring 47. As such, the cord reel 43 rotates to release
the cord
13A and thus the line 49 so as to lower the sheet of drapery material 30. The
worm
section 472 is wound further (i.e., store energy) and the worm section 471 is
loosened
to compensate the further winding of the worm section 472 during the release.
Such
serves as a counterweight of the sheet of drapery material 30 so as to reach a
balance. As a result, the sheet of drapery material 30 is adapted to stay at
any one of
a plurality of positions from the fully raised position to the fully lowered
position by
stopping the cord reel 43.
Referring to FIGS. 8, 9, and 10, there is shown a winding mechanism 40 in
accordance with a second preferred embodiment of the invention. The winding
mechanism 40 of the second preferred embodiment is identical to that of the
first
preferred embodiment of the invention with certain exceptions. Cord 13A is
replaced
by a loop 13B having one end connected to the cord reel 43 and the other end
wrapped around the bight section 491 of the line 49. Referring to FIG. 11, it
shows
another configuration of the second preferred embodiment of the invention. In
this
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configuration, cord 13A is replaced by loops 13C each having one end connected
to
the cord reel 43 and the other end wrapped around the bight section 491 of the
line
49.
Referring to FIGS. 12 in conjunction with FIG. 2, an upward pulling of the
stiffener
strip 20 by the hand together with the compression force of the spring 47 can
oveircome the weight of the sheet of drapery material 30. For reaching a
balance, the
worm section 472 coupled to the first drum 44 begins to release and the worm
section
471 coupled to the second roller 45 begins to wind. A force exerted onto the
cord reel
43 by the spring 47 is thus adjusted. Also, a rotation of the first drum 44
will cause the
cord reel 43 to rotate the same for winding the line 49. Likewise, the sheet
of drapery
material 30 is adapted to stay at any one of a plurality of positions from the
fully raised
position to the fully lowered position by stopping the cord reel 43.
Referring to FIGS. 2 and 3 again, the winding mechanism 40 further comprises a
retaining member 50 including an elongate seat 51 engaged with a bottom
surface of
the stiffener strip 20 and two upwardly curved snapping edges 52 along front
end rear
edges of the seat 51 for clamping the stiffener strip 20. The provision of the
retaining
merriber 50 aims at facilitating the upward or downward pulling the stiffener
strip 20 by
the hand.
Referring to FIGS. 13 and 14, a third preferred embodiment of winding
meclianism 60 of blind according to the invention is shown. The winding
mechanism
60 of the third preferred embodiment is identical to that of the first
preferred
embodiment of the invention with certain exceptions. The winding mechanism 60
comprises a case 61 open to its bottom, the case 61 having an internal space
62 for
mounting a third drum 63 and a fourth drum 64 therein. The winding mechanism
60
further comprises two shafts 65 each having two ends fixed on two opposite
walls of
the case 61 with the third drum 63 and the fourth drum 64 rotatably put
thereon. An
S-shaped tape spring 66 is interconnected the third drum 63 and the fourth
drum 64. A
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free end of the worm section 66 is fixed on the third drum 63. A cord reel 67
is
coaxially formed at one side of the third drum 63. A long cord 68A is wound
around the
cord reel 67. One end of the cord 68A passes a slit on one side surface of the
case 61
to coiuple to a line 70. As such, the cord 68A and the line 70 can operate as
a whole.
F2eferring to FIGS. 15 and 16, a fourth preferred embodiment of winding
mechanism 60 of blind according to the invention is shown. The winding
mechanism
60 of the fourth preferred embodiment is identical to that of the third
preferred
embodiment of the invention with certain exceptions. The winding mechanism 60
comprises a case 61 open to its bottom, the case 61 having an internal space
62 for
mouriting a third drum 63 and a fourth drum 64 therein. The winding mechanism
60
further comprises two shafts 65 each has two ends fixed on two opposite walls
of the
case 61 with the third drum 63 and the fourth drum 64 rotatably put thereon.
An
S-shaped tape spring 66 is interconnected the third drum 63 and the fourth
drum 64. A
free end of the worm section 66 is fixed on the third drum 63. A cord reel 67
is
coaxially formed at one side of the third drum 63. A long cord 68A is wound
around the
cord reel 67. One end of the cord 68A formed as a loop 68B passes a slit on
one side
surface of the case 61 to wrap around a bight section 71 of the line 70. As
such, the
loop 68B and the line 70 can operate as a whole.
In practice, each of the springs 47 and 66 can control one or more cord reels
43
and 67 for accommodating different sizes of the blind. In brief, the invention
is safe
and smooth in its operation.
While the invention herein disclosed has been described by means of specific
embodiments, numerous modifications and variations could be made thereto by
those
skilled in the art without departing from the scope and spirit of the
invention set forth in
the claims.
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