[0001] The present invention relates to tilter for Venetian blind, particularly a tilter
mechanism to rotate headrail of the Venetian blind directly.
[0002] Each Venetian blind is composed of a plurality of vertical or horizontal slats running
in parallel, tilting of which can adjust indoor darkness and preserve confidence in
personal living. It is being extensively used in offices and homes. The conventional
horizontal Venetian blind being used can have its slats tilted and lifted, and comprises
mainly a rectangular sectioned and non-rotary headrail, a foot rail, two or more ladders
each including an outer ladder and an inner ladder suspending from the headrail to
the foot rail to support a plurality of slats with a plurality of connecting tapes
located between the outer and inner ladders, and a tilter within the headrail and
a transmission device therefor to tilt the slats. The tilter and the transmission
device are incorporated with a handle to tilt the slats manually, and are substantially
in a form of a drum driven by a worm drive through the handle for rotation, include
at least to tilt drums each wound by a ladder to support the ladder, and a transmission
shaft located between the tilt drums to rotate the tilt drums simultaneously. When
the handle is operated, the ladders are moved linearly by the tilter, transmission
shaft and the tilt drums, the outer and inner ladders are moved in two opposite directions
to tilt the slats between them.
[0003] The conventional tilter for Venetian blind is firmly secured to a headrail, and has
a worm drive and a plurality of transmission shafts to rotate the respective ladder
drums suspending the slats. Such a tilter has a quite complicated structure, and hence,
its production cost is high. Moreover, it is hardly to implement mass production with
automatic assembly process, and it indeed has the following defects:
(1) In general a ladder drum is located near each end of the headrail to maintain
a good balance for the slats, but a transmission shaft having a length nearly equal
to the length of the headrail must be provided between the ladder drums, and a plurality
of bearings must be placed to support such a long transmission shaft, hence, the overall
weight of the Venetian blind is significantly increased, the long transmission shaft
means a relatively long momentum arm, and a considerable large force is required to
rotate the ladder drums simultaneously for tilting the slats to a desired angle.
(2) Such sophisticated tilter required assembly at factory, and its installation position
can not be changed after it is assembled to satisfy the user's habit or environmental
requirements. Production and use of which are hence inconvenient.
(3) The worm drive, bearing and gears in the conventional tilter will lose its transmission
efficiency due to improper use, prolonged exposure to dusts and other factors which
damage proper engagements among its components.
[0004] The present invention provides a revolutionary design concept for tilter of Venetian
blind to overcome the above defects. The tilter according to the present invention
can drive the headrail of the blind to rotate directly, and consequently the ladder
holders firmed fixed to the headrail to rotate simultaneously without the use of worm
drive, gears, long transmission shaft and bearings as needed in the conventional tilter.
Tilter mechanism according to the present invention comprises a hollow drum secured
to window frame or door frame, an end cover, and a rotary mechanism extended out of
the drum and connected to the tubular headrail so that pulling of a tilt cord can
drive the rotary mechanism to rotate and consequently rotate the tubular headrail
simultaneously so as to tilt the slats suspending from the tubular headrail to any
desired angle.
[0005] Therefore, the main object of the present invention is to provide a tilter mechanism
for Venetian blind with minimum components and simple structure. It is a design that
permits mass production with automatic assembly process at low production cost.
[0006] Another object of the present invention is to provide tilter mechanism for Venetian
blind which permits efficient and prompt adjustment of slat tilting, assures easy
operation, long service life and minimum failure possibility in comparison with the
conventional tilter.
[0007] Another object of the present invention is to provide a tilter mechanism which can
be installed at either end of the headrail to satisfy different user's habit and different
indoor installation requirements.
[0008] Another object of the present invention is to provide a tilter mechanism for Venetian
blind to be supplied to the general consumers in the form of a "DIY" kit to permit
assembly and replacement of slats by the consumers.
[0009] The drawings disclose an illustrative embodiment of the present invention which serves
to exemplify the various advantages and objects hereof, and are as follows:
Fig. 1 is a perspective view of a horizontal Venetian blind with a tilter mechanism
according to the present invention;
Fig. 2 is a front view of the Venetian blind as installed to a window frame;
Fig. 3 is a magnified side view of the Venetian blind;
Fig. 4 is a perspective fragmented view of the tilter mechanism according to the present
invention;
Fig. 5 is a perspective view illustrating wound of a tilt cord around a rotary mechanism
in the tilter mechanism, in which the rotary mechanism is shown with dashed lines;
Fig. 6 is a perspective view of the tilter mechanism according to the present invention;
Fig. 7 is a longitudinal sectional view of the tilter mechanism according to the present
invention;
Fig. 8 is a sectional view taken along line 8-8 in Fig. 7;
Please refer to Figs. 1 through 3, the Venetian blind (10) incorporated with the
tilter mechanism (20) according to the present invention comprises mainly a rotary
tubular headrail (11), a rotary tubular foot rail (12), two ladder sets (13) extending
from the headrail (11) to the foot rail (12) to support a plurality of parallel horizontal
slats (90), a tilter (20) located at any end of the headrail (11), and a lifter (19)
located at another end of the headrail (11). Each ladder set (13) is composed of an
outer ladder tape (14), an inner ladder tape (15), a plurality of horizontal connecting
tapes (16) each beneath a slat (90) to support a slat (90), and two pull cords (17a
and 17b) extending from the headrail (11) to the foot rail (12) and substantially
connected to a lift cord (18) for lifting and lowering of the slats (90) outside the
blind (10). When the lift cord (18) is pulled downward manually, the pull cords (17a
and 17b) are raised synchronously to lift the foot rail (12) so that the slats (90)
are displaced upward and overlaid in sequence to close the blind (10). The ladder
sets (13) are placed between an end of the headrail (11) and an end of the foot rail
(12) at the same side directly, and retained between the headrail (11) and the foot
rail (12) with a ladder holder (not shown) indirectly. When the headrail (11) is rotated,
the ladder tapes (14 and 15) at two opposite sides of the headrail is cause to perform
vertical movement linearly in two opposite directions so that the slats supported
by the horizontal connecting tape (16) are tilted for a same degree accordingly.
[0010] Please refer to Figs. 4 thru 8, the tilter (20) to rotate the headrail (11) directly
for tilting of the slats (90) comprises mainly a hollow drum (22) secured to a window
frame (93), an end cover (24) to close the hollow drum (22). The hollow drum (22)
has a pair of upward extended ribs (26), and the end cover (24) has a cross slot (28).
The drums (22) can be easily secured to a side of the window frame (93) with the extended
ribs (26) or the cross slot (28) by means of any conventional fasteners. the tilter
(20) includes further a rotary member (31). The rotary member (31) is a hollow structure
with an extended fixing section (33) and a pulley section (32). The pulley section
(32) has two cord ways (34 and 35) formed by three rims. A notch (36) is formed at
the middle rim so as to connect the cord ways (34 and 35) are connected together.
As shown in Fig. 5, a tilt cord (37) made of soft material is wound from a cord way
(34) to the other cord way (35) through the notch (36). The tilt cord (37) winding
on the cord way (34) has an overlapped portion (38). By friction between the tilt
cord (37) and the surface of the cord ways (34 and 35), pulling of the tilt cord (37)
can rotate the rotary member. The extended fixing section (33) has four notches (39)
arranged annularly in equal distance. As shown in Figs. 6 and 8, the extended fixing
section (33) can be partly extended from the drum (22) into the tubular headrail (11),
and its four notches (39) are engaged with a cross driven element (40) in the tubular
headrail (11) when the rotary member (31) is installed into the drums (22). Therefore,
when the rotary member (31) is rotated, the tubular headrail (11) is driven to rotate
simultaneously.
[0011] The drum (22) can be secured to either end of the headrail (11), and hence it is
designed with a cord outlet (41) in the middle of its bottom side, and two symmetric
cord outlets (42 and 43), one at the left side and the other at the right side. As
shown in Figs. 6 and 7, both ends of the tilt cord (37) are extended out of the drum
(22) through either the cord outlet (42) or another cord outlet (43) so that an end
of the tilt cord (37) can be pulled indoors and consequently the rotary member (31)
and the tubular headrail (11) can be driven to rotate clockwise or counterclockwise,
and then the ladder sets (13) are driven to pull the slats (90) to rotate to the desired
angle.
[0012] The drum (22) has a connecting section (45) composed of a plurality of elastic connecting
elements (44) arranged annularly in equal distance near an end of the tubular headrail
(11). Each elastic connecting element (44) has a wedged end (46) extending outward.
When the connecting section (45) of the drum (22) is fixed in the tubular headrail
(11), the wedged ends (46) of the respective elastic connecting elements (44) are
retained in a retaining groove (47) in the tubular headrail (11) so that the drum
(22) is rotatably connected to the tubular headrail (11) without risk of disengagement.
[0013] In comparison with the conventional tilter, the tilter mechanism according to the
present invention has the following advantages:
(1) It drives the headrail to rotate directly and consequently causes the ladder tapes
at both side of the ladder to perform vertical movement linearly in two opposite directions
in order to tilt the slats. In comparison with the conventional tilter which has a
fixed headrail and uses a handle to drive a worm drive, a transmission shaft and a
gear train to rotate the ladder drums for opposite linear movement of the ladder tapes,
the present invention has less component and simple structure which permits mass production
with automatic assembly process at low production cost.
(2) A tilt cord is used to tilt the slats, which means high efficiency in comparison
with the conventional operating handle. Since no transmission shaft of long momentum
is used, the slats can be tilted promptly with less effort. It is easy to operate,
durable and requires less service in comparison with the conventional tilter.
(3) The tilter can be installed at either end of the headrail to satisfy different
user's habit and different indoor installation requirements.
(4) It can be supplied to the general consumers in the form of a "DIY" kit to permit
assembly and replacement of the tilter by the consumers.
[0014] Many changes and modifications in the above described embodiment of the invention
can, of course, be carried out without departing from the scope thereof. Accordingly,
to promote the progress in science and the useful arts, the invention is disclosed
and is intended to be limited only by the scope of the appended claims.
1. A tilter mechanism for a Venetian blind comprising a rotary tubular headrail, a rotary
tubular foot rail, at least two ladder sets fixed between the headrail and the foot
rail each comprising an inner ladder tape and an outer ladder tape running in parallel
with each other as well as a plurality of equidistant and parallel horizontal connecting
tapes each support a slat between the inner and outer ladder tapes, a plurality of
slats above the respective horizontal connecting tapes, and a tilter comprising:
- a fixed hollow drum secured to the headrail;
- an end cover firmly secured to the hollow drum to define in the hollow drum a middle
cord outlet and two cord outlets symmetrically located on two ends of the hollow drum;
- a hollow rotary mechanism rotatably fixed in the hollow drum, including a pulley
section and an fixing section extended out of the hollow drum and engaged with the
headrail for synchronous motion;
- a tilt cord made of soft material, wound around the pulley section and having an
end extended out of the cord outlet, providing an adequate friction with the pulley
section so that the rotary mechanism and the headrail are rotated synchronously by
pulling of the tilt cord, and consequently the inner ladder tape and outer ladder
tape are driven by the rotating headrail to perform vertical movement linearly in
two opposite directions so that the slats are tilted for the same degree of rotation
accordingly.
2. A tilter mechanism as claimed in Claim 1 wherein the pulley section has two cord ways
formed by three rims and a notch is formed at the intermediate rim for connection
between the two cord ways.
3. A tilter mechanism as claimed in Claim 2 wherein the tilt cord is wound from a cord
way to the other cord way through the notch, and the tilt cord wounding between the
two cord ways has an overlapped portion.
4. A tilter mechanism as claimed in Claim 1 wherein the extended fixing section has four
notches arranged annularly in equal distance, and the extended fixing section can
be partly extended from the drum into the tubular headrail, and its four notches are
engaged with a polygonal driven element in the tubular headrail.
5. A tilter mechanism as claimed in Claim 1 wherein the drum has a connecting section
composed of a plurality of elastic connecting elements arranged annularly, the headrail
has a connecting slot corresponding to such connecting section so that the drum can
be rotatably engaged with the headrail.
6. A tilter as claimed in Claim 1 wherein the drum can be secured to window frame.