Note: Descriptions are shown in the official language in which they were submitted.
TENSIONER AND SAFETY ENCLOSURE FOR WINDOW BLIND LOOP DRIVE
FIELD OF THE INVENTION
The invention relates to a tensioning device for tensioning an endless loop
control element in a
window blind and particularly relates to a blind operating mechanism and an
endless loop blind
.. control element for operating the blind mechanism and having; a channel
extending from an
upper end to a lower end, with the endless loop blind control element enclosed
within the
channel; a connector supporting the upper end of the channel adjacent to the
blind operating
mechanism; and, the tensioning device on the lower end of the channel.
The invention also discloses a narrow profile control element having a
sprocket wheel with the
channel, connector and tensioning device.
BACKGROUND OF THE INVENTION
Blinds for building openings, eg windows, doors and the like, may be operated
either simply
down and up, in the case of eg. roller blinds, or in the case of eg. vertical
shade panels, the
vertical shade panels may be rotated open or closed.
The control elements for these blind operations are usually in the form of an
endless cord or
chain. The control element simply hangs down along one side of the building
opening, in an
endless loop.
Other forms of blinds and window coverings may also be operated by means of an
endless
control element hanging in a loop.
In the past this system has been used . In some cases a pendant weight was
located on the
loop to assist in controlling it. In US Patent 8539645 Inventor Mario Marocco
showed an earlier
form of a lock for a blind cord loop in which a spring operated lock is used.
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However building codes are now requiring that the endless loop type of control
element be
guided and controlled at its lower end; and also be tensioned, so as to
attempt to prevent the
possibility of the element creating a hazard to children , handicap persons or
pets. Accordingly it
is desirable to provide improved tensioning devices.
Furthermore and generally speaking clutch mechanisms have been used in the
window
covering industry to inhibit the unwanted unrolling of window blinds. These
clutch mechanisms
have generally been used with sprocket wheels located at the end of window
blinds. However
there is a need to minimize the gap between the end of the blind and window
frame to minimize
the amount of unwanted light infused into a room. Generally speaking the use
of spur gears and
worm or bevel gears have not been widely used as they tend to increase the gap
between the
end of the window shade and window frame. Moreover there is a further need to
minimize the
thickness of a sprocket wheel. Attempts to reduce the thickness of such drives
tended to
produce a drive that flexed and wandered , and they tended to "bind" when
used.
Moreover there is great interest to provide a child safe environment so that
it is desirable to use
a single rod mechanism to activate the gear drive in a window shade.
For example US 5752558 illustrates a tensioning device is to be used with a
control cord of a
blind assembly and includes a hollow casing which confines a vertically
extending receiving
space and which has an open top end portion and a bottom end provided with a
pivot portion. A
pivot unit mounts rotatably the pivot portion of the casing on a wall body. A
cord engaging unit
has a pulley formed with a cord engaging groove for passing over of the
control cord, and a
base slideably provided in the receiving space and having a front side formed
with a pulley
receiving recess. The pulley is mounted rotatably to the base in the pulley
receiving recess. The
base further has a top wall formed with a pair of notches which permit
extension of parallel
sections of the control cord that passes over the pulley. A cover member is
mounted on the
open top end portion of the casing, and is formed with a pair of slits that
are aligned with the
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notches in the top wall of the base and that permit extension of the parallel
sections of the
control cord therethrough. A force generating member is provided in the
receiving space and
forces the base of the cord engaging unit downwardly in the casing in order to
permit tensing of
the control cord when the casing is mounted on the wall body.
Another arrangement is shown in US 5845696 which shows a blind cord safety
device for use in
controlling an adjustable blind having a looped control cord and a looped
control chain by
enclosing the loops has housing within which are disposed a rotatable wheel
adapted to engage
the chain loop thereabout and a U-shaped cord loop receiver adapted to receive
the cord loop in
a peripheral groove formed thereon. The receiver is mounted within the housing
so as to permit
limited longitudinal but not lateral movement of the receiver within the
housing. A spring is
disposed within the housing between the receiver and the housing top so as to
normally urge
the receiver away from the housing top so as to avoid slack in the cord as a
result of the cord
stretching over time as a result of use.
Also US 7114544 describes a tensioner for the control element of a covering
for an architectural
opening includes a base member attachable to a support surface adjacent to the
architectural
opening with the base member supporting an upstanding plunger about which a
surrounding
housing is adapted to slide. A coil spring biases the housing downwardly
relative to the plunger
and a rotatable pulley is mounted in an open top of the housing around which
an endless
operating element for a covering for an architectural opening extends.
Applicant has also filed a previous patent application for a tensioner which
has been allowed.
The tensioner described herein has a funneled upper end to draw the endless
loop together so
as to make it more difficult to access the endless loop.
These and other prior art devices and blind controls attempt to block out the
light coming from
outside the window particularly when a person desires to sleep.
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It is an object of this invention to provide an improved blind control for a
window covering.
It is another object of this invention to locate the drive mechanism to
minimize the gap between
the end of the window shade and window frame.
Yet another object of this invention relates to the use a single rod means
depending from the
control module to activate the drive mechanism in a safe and secure manner.
It is another object of this invention to provide a narrow profile control
module for a window
shade to minimize light from outside the window infiltrating the room.
SUMMARY OF INVENTION
It is an aspect of this invention to provide a spring loaded tensioning device
for tensioning an
.. endless loop blind control element to be secured in position on a window
opening; comprising; a
housing for housing said endless loop blind control element; a hinged flap
portion on said
housing , said hinged flap portion being operable between an open position for
insertion of a
portion of the control element into said housing and a closed position for
securing the control
element in said housing; a funnel portion on said housing for drawing said
endless loop
together.
In one embodiment the housing comprises a first shell portion and a second
shell portion , and
wherein one of shell portions presents said hinged flap. In another embodiment
the first and
second shell portions engage each other to present an upper end and a lower
end and define a
cavity therein and wherein the hinged flap portion is disposed in said upper
end of one of said
first or second shell portions. Another embodiment presents a spring loaded
tensioning wherein
said funnel portion is disposed in said upper end. In yet another embodiment
there is a
moveable lock in the housing shell, moveable between a locking position in
which it clamps onto
said element, and a released position in which said lock is free of said
control element.
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It is also an aspect of this invention to provide a blind operating mechanism
and an endless loop blind
control element for operating the blind mechanism and comprising; an enclosure
having an upper end
and a lower end, with the endless loop blind control element enclosed within
the enclosure between the
upper end to the lower end of said enclosure; a connector supporting the upper
end of the enclosure
adjacent to the blind operating mechanism and depending downwardly from it;
and, a tensioning device
on the lower end of the enclosure for tensioning the endless loop control
element; said tensioning
device including a housing having a hinged position being operable between an
open position for
insertion of a portion of said endless loop blind control element and a closed
position for securing the
endless loop blind control element in the tensioning device.
In one embodiment of the invention the enclosure comprised a channel extending
between said upper
end to said lower end for containing said endless loop blind control element
within said channel.
In another embodiment the channel includes a pusher means for pushing a
portion of said endless loop
blind control element out of said channel between an operable position for
manipulating said endless
loop blind control element to move a blind and a retracted position whereby
the pusher means and said
portion of said endless loop blind control element retracts back into said
channel.
The channel has an open side and further includes a cover to cover said open
side of said channel
from said upper end to said lower end.
In one embodiment the channel includes the pusher means for pushing a portion
of said endless loop
blind control element out of said channel between an operable position for
manipulating said endless
loop blind control element to move a blind and a retracted position whereby
the pusher means and said
portion of said endless loop blind control element retracts back into said
channel , and the cover
includes an aperture aligned with said pusher means to receive said portion of
said endless loop blind
control element.
The endless loop blind control element can either be a chord or chord and ball
chain or the like.
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In one aspect the tensioning device includes a housing having a hinged portion
being operable
between an open position for insertion of another portion of said endless loop
blind control element and
a closed position for securing the element in the tension device. In one
embodiment the the tensioning
device includes guide surfaces to guide said another portion of said endless
loop blind control element
there around.
Furthermore the housing comprises a first shell portion and a second shell
portion , and wherein one of
shell portions includes said hinged portion where the hinged portion comprised
a hinged flap and
wherein said flap includes a distal portion from said hinged portion to engage
said lower end of said
channel.
It's another aspect of this invention to provide a blind having a blind
operating mechanism and an
endless loop blind control element for operating the blind mechanism and
comprising; an enclosure for
the blind control element, the enclosure defining an upper end and a lower end
with the element
concealed within the enclosure from the upper end to the lower end; a
connector supporting the upper
end of the enclosure adjacent to the blind operating mechanism and depending
downwardly from it;
and a tensioning device on the lower end of the enclosure for tensioning the
endless loop control
element; wherein said tensioning device comprises a housing having a first
shell portion and a second
shell portion, and wherein one of the shell portions includes a hinged flap
being operable between an
open portion for insertion of a portion of said endless loop bind control
element and a closed portion for
serving the element in the tensioning device.
In a further embodiment there is provided a sprocket wheel adjacent one end of
said blind and
engageable with said endless loop to control the movement of said blind;
moreover the blind operating
mechanism for the window shade for a window opening has a narrow profile
wherein the gap is
between 4 to 8 millimeters and said endless loop blind control element is
contained out of reach by
children.
It is another aspect of the invention to provide a connector for a window
blind comprising: a housing
having an upper end and a low end , and defining a cavity between said upper
end and lower end ; said
upper end adjacent a blind operating mechanism for receiving a blind loop
element from the blind
operating mechanism through said upper end, through said cavity and
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out the lower end, said lower end being smaller than said upper end to bring
said loop element
closer together. In one embodiment the connector for a window presents a
funnel from said
upper end to said lower end.
It is yet another aspect of this invention to provide a stopper for an open
channel receiving an
endless loop element therein , said stopper moveable relative said channel to
limit the extension
of said endless loop from said channel.
These and other objects and features shall now be described in relation to the
following
drawings.
IN THE DRAWINGS
Figure 1 is a perspective view of a window blind with the tensioning device,
channel and
connector.
Figure 1A shows the connector, enclosure and tensioning device.
Figure 1B shows the connector, a telescoping enclosure and joint.
Figures 2a and 2b, 2c, and 2d show the tensioning device first housing shell
and second
housing shell.
Figure 3A and 3B are top views of the tensioning shell halves.
Figures 4A, 4B, 4C are partial perspective view of the channel showing a
pusher means, with
and without a cover.
Figures 5A and 5B show the tensioning device engage the lower end of the
channel while
Figure 5C shows the cover in perspective cross section.
Figure 6 is a perspective view of the connector engaging the upper end of
another embodiment
of the enclosure.
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Figures 7A, 7B and 7C are views showing the endless loop engaging a sprocket
wheel where
the endless loop is guided through a connector, and another embodiment of
telescoping
channels with a connector at the top end thereof.
Figure 8A and 8B are cross sections of different embodiments of the channel.
Figure 9 is a perspective view of the tensioning device
Figures 10A, 10 B, and 10C are side views of the tensioning device,
DETAILED DESCRIPTION OF THE INVENTION
Like parts are given like numbers throughout the figures.
Like parts are given like numbers throughout the figures.
Description of a specific embodiment
Figure 1 illustrates a window 10 with an opening 12 and a border 14 which has
a window blind
16 adapted to move up and down within the opening 12.
For purposes of illustration Figure 1 depicts a simple roller blind 18 mounted
on the frame 14.
The blind 18 has a sheet of suitable material wound upon a roller which may be
lowered or
raised. The roller is operated by a controlled element depicted generally as
18.
The element 20 can comprise a typical chain type element with a series of
balls 22 connected
by a wire or cord 24 in a manner well known to those persons skilled in the
art. The element 20
may also comprise a cord. The element 20 comprises an endless loop and engages
a gear
drive in the mechanism of the blind.
The roller blind is shown by way of example as various other forms of blinds
employ a
continuous loop type of control element 20 and the invention to be described
herein is
applicable to all of them and is not confined solely to the roller blind as
shown.
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Moreover different forms of drive mechanisms can be used and the invention is
described
herein as applicable to a variety of forms of control elements that utilize
ball and chain or cord
mechanisms.
Recent building codes require that the endless loop be held in tension between
the blind at the
upper end and a tension device 30 at the lower end thereof as a safety
feature.
The tension device 30 is shown in more detail in figures 1A, 2A, 3B, as well
as figures 3A and
3B.
The tensioning device 30 comprises a housing 32 having a hinged portion 38
being operable
between an open position as shown in figure 10C for insertion of a portion of
the endless loop
blind control element 20 and a closed position as shown in Figure 10B for
securing the element
in the tension device 30. More particularly the housing 32 comprises a first
shell portion 36A
and second shell portion 36B as shown in Figures 3A and 3B and wherein one of
the shell
portion includes the hinged portion or hinged flap 38.
Furthermore the tension device 30 includes guide surfaces 40 to guide a
portion of the endless
15 loop blind control element 20 there around.
The first shell portion 36A and second shell 36B can be formed from synthetic
plastic or other
suitable material and have upper and lower ends 42 and 44 respectively. The
lower end 42
displays generally semi-circular profile as shown. Each shell portion 36A and
36B include
upstanding sidewalls 46A and 46B and extend from the lower end 42 upwardly and
terminate
20 adjacent the upper end 44. The upstanding sidewalls 46A and 46B present
reduced height
portions 48A and 48B so as to define an opening 50.
The housing 32 and in particular the first shell portion 36A and second shell
portion 36B define
a cavity there between.
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Each shell housing portion 36A and 36B includes a support ledge 52A and 52B
which cooperate
to contact each other once the first shell housing portion 36A and second
shell housing portion
36B register with each other.
Located at the upper end 44 of the first shell housing portion 36A and second
shell housing
.. portion 36B and spaced from the upstanding side walls 46A and 46B is a
fixed hub 54 which
presents the guide or glide surfaces 40 around which the control element 20
can freely slide.
The hub 54 acts like a pulley though it is stationery.
Each first and second shell hub housing portion 36A and 36B present post or
plug 56 that
register with receiving holes 58 so that the two halves can snap together. One
of the housing
.. shells 36A and 36B include a notch 58 that is adapted to receive a tab 60
as best seen in Figure
1A so as to help to register the first and second shell housing 36A and 36B
together.
Adjacent the upper end 44 of one of the shell housing units 36A and 36B is a
flexible self-hinge
groove 34 defining the hinge so as to permit the flap 38 to be opened and
closed as previously
described. This allows the upper end 44 of the second shell housing 36B to be
flexed outwardly
and inwardly like a flap to enable service persons to install the element 20.
Also it permits a
person to mount the tensioner 30 onto an existing window blind having an
endless loop 20
without having to dismantle any of the existing hardware. Thus the tensioner
30 can be used as
a retrofit item into existing window blind hardware.
A captive slide lock 60 is located within the housing 30. The slide lock 60
includes a spring
guide rod 62 which receives and guides a spring 64. One end of the spring 64A
abuts against
the upper inner end of the slide lock 60 while the opposite end 64B abuts
against the ledge 52A
and 52B.
At the other end of the slide lock 60 there are optionally one or two
upstanding rows of teeth 66
or engaging means 66. The teeth 66 or element engaging means 66 are presented
so as to
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engage with the element 20 when it passes over the hub 54 to prevent the
element 20 from
passing around the hub 54 and lock it into place. Furthermore the engagement
means 66 or
teeth 66 act as another layer of safety as the teeth 66 will "bite" the
control element 20 if the
tensioner 30 is not secured to the window frame 14 by fastener 59 ( see Figure
1A as the spring
64 will expand and cause the "teeth" to bite into the endless loop 20 and
prevent the endless
loop from moving until properly secured. Alternatively the slide lock 60 may
eliminate teeth 66
and present a surface to contact the endless loop. In yet another embodiment
the engaging
means 66 and slide lock 60 may be eliminated.
At the opposite end of the slide lock 60 there is screw housing sleeve 68
which permits a screw
fastener 59 to be passed there through. A pair of finger buttons 70 extend
outwardly from a slide
lock 60 passing through the holes 50.
In order to secure the tension device 30 to the window frame 14 a screw 59 is
received through
the screw receiving slot 72 as shown in Figure 1. Each shell housing 36A and
36B includes a
screw receiving slot 72A and 72B respectively. The fastener 59 that passes
through the screw
receiving slot 72 also passes through the screw housing sleeve 68 of the slide
lock 60 as
shown.
In operation the serviceperson would manipulate the finger button 70 and slide
the slide lock 60
downwardly compressing a spring 64 so as to open the space around the hub 54.
Thereafter a
portion of the loop of element 20 is placed around the hub 46 for contact with
the guides 40.
Thereafter the flap 38 is closed and the finger buttons 70 released. The slide
lock 60 will react
when the pressure of the spring 64 and the teeth or element engaging means 66
will grip the
element 20 against the hub 54.
The tensioner 30 in one embodiment can be used by itself as the tensioner 30
includes side
wall 46a and 46b that converge toward each other in the vicinity of the upper
end 44 so as to
"funnel" the endless loop 20 together, and more particularly endless loop
portion 20a and 2b
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"close together". In another embodiment the invention comprises the tensioner
in combination
with the connector 90.
Furthermore the connector 90 presents a wider opening at the top 90a thereof
than the lower
open end 90b so as to "funnel" the endless embodiment the invention comprises
a connector 90
for receiving the loop 'together' making it more difficult to get between the
elements 20a and
20b. In one embodiment the invention comprises a connector adjacent a blind
control
mechanism for receiving the endless loop into an opening at the upper end 90a
thereof through
said connector and out the lower end 90b thereof, the lower end being smaller
than the upper
end thereof so as to "funnel" or bring the endless loop 20a and 20b closer
together than when
entering the upper end 90a so as to bring the loop elements closer together.
Accordingly the
invention includes using the connector by itself, or alternatively using the
connector 90 in
combination with the tensioner 30, or alternatively the combination of the
tensioner 30,
enclosure 80 and connector 90.
The blind operating mechanism 18 also comprises an enclosure 80 extending from
an upper
.. end 82 to a lower end 84 with the endless loop button control element 20
enclosed within the
enclosure 80 between the upper end 82 and the lower end 84 of the enclosure
80.
The blind operating mechanism 18 also includes a connector 90 supporting the
upper end 82 of
the enclosure 80 adjacent to the blind operating mechanism and depending
downwardly from it.
The tension device 30 is located at the lower end 84 of the enclosure 80 for
tensioning the
endless loop control element 20.
The enclosure 80 comprises a channel 86 as shown in Figure 4A, 4B, and 4C
which channel
extends between said upper end 82 and said lower end 84 for containing the
endless loop blind
control element 20 within the channel 86.
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The channel 86 includes a pusher means 88 as best in figure 4A and 4B. The
pusher means 88
comprises a paddle surface 90 that can be moved by moving element or handle 92
connected
to the paddle 90 by means of a shaft that extends through one of the sidewalls
86A and 86B.
The channel also includes a bottom wall 86C. Accordingly the pusher means 88
pushes a
portion of the endless loop blind control element 20 out of the channel
between an operable
position for manipulating the endless loop blind control element 20 to move
the blind up and
down; to a retracted position whereby the pusher means 88 and a portion of the
endless loop
blind control element 20 retracts back into the channel 86 between the
sidewalls 86A and 86B
down towards the bottom wall 86C.
More particularly the pusher means 90 pushes two portions 20a and 20b of the
endless loop 20
out of the enclosure or channel 80 in the operable position. Thus a person
will have the choice
ton either move the portion 20a so as to move the blind 16 either up or down
or to move the
other portion 20b so as the move the blind 16 in the opposite direction ie
either down or up.
As can be seen the channel 86 includes an open side. Furthermore the operating
mechanism
may also include an adjustable stopper or limiter, 94 that is moveable along
the open end of the
channel 80 from the upper end 82 to the lower end 84 so as to be able to
adjust how far or how
much of the endless loop 20 and particularly the portions 20a and 20b are
presented outside the
channel walls 86a and 86b and thus provide and added safety feature to the
blind operating
mechanism. For example if the stopper 94 is presented close to the pusher
means 88 then a
smaller portion of the endless loop 20a and 20b is exposed as compared to
moving the stopper
means 94 further away from the pusher means 90. In other words the stopper or
limiter is a
safety device that limits the extension of the loop beyond the enclosure 80.
The channel in one embodiment as shown in Figure 8A includes a recess 96A and
96B at the
upper ends of the sidewalls 86A and 86B respectively. The recesses 96A and 96B
are adapted
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to receive projections 98A and 98B of stopper 94 so as to snap the stopper 94
onto the channel
86.
The hinge portion 34 defines a hinge flap 38 which has a distal portion 38A
for engaging with
the lower end 84 of the channel 86 as shown in Figure 9 and "snaps" into
place.
The invention as described relates to a blind 18 having a blind operating
mechanism 18 and an
endless loop blind control element 20 for operating the blind 18 and
comprises:
(a)
an enclosure 80 for the blind control element 20, the enclosure 80 defining an
upper end 82 and a lower end 84 with the element 20 concealed within the
confines of the enclosure 80 from the upper end 82 to the lower end 84;
(b) a connector
90 supporting the upper end 82 of the enclosure 80 adjacent to the
blind operating mechanism and depending downwardly therefrom; and
(c) a
tension device 30 at the lower end 84 of the enclosure 80 for tensioning the
endless loop control element 20.
The channel 86 also comprises telescoping first and second channel portions
87A and 87B as
shown in Figure 7C. In the embodiment shown in Figure 7C, 87a has the profile
shown in
Figure 8B while 87b has the profile shown in Figure 8A. However this is just
one example of a
telescoping enclosure 80 and other profiles may be used.
Alternatively the telescoping portions 87A and 87B may have the cross-
sectional profile as
shown in figure 8B which can be secured together at the appropriate telescopic
length by
utilizing a fastener 100 that extends between the first telescoping channel
87A towards the
second telescoping channel 876 by means of extending through a ridge portion
87C presented
by the second telescoping channel 87B.
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The channel 80 may be manufactured and sold in pre-selected lengths, for
example 3 feet. The
tensioner 30 can also be sold separately or as a kit with the connector 90 for
the retrofit market.
The channel can be made from plastic aluminum, metal or other suitable
material and cut to any
desired length. If he widow height is larger than the pre-selected length of
the channel 80 then a
telescoping length of enclosure 87A may be utilized with the channel 80 ; once
adjusted to the
desired length the telescoping members 80 and 87a may be secured by fastener
100.
If the height of the window is extremely large a joint 200 as shown in Figure
1B can be used to
join telescoping member 87a to connector 90.
The connector 90 which supports the upper end 82 of the channel 86 comprises a
connector
upper end 90a to guide the endless loop 20 towards the channel 86 and a
connector lower end
90b to engage with the upper end 82 of the channel 86. The connector 90 is
funnel shaped and
funnels the endless loop close together at the lower end so as to present the
endless loop 20a
and 20b close together to inhibit access to the endless loop 20.
Although the invention has been described in one embodiment or example to be
well suited to a
retrofit market , the invention is also applicable as product for a new or
original widow blind.
The invention as described herein also shows in Figure 11 the use of a
sprocket wheel 110
adjacent to one end of the blind 18 and engageable with the endless loop 20 to
control the
movement of the blind.
In particular as shown in Figure 11 there is a blind operating mechanism 18
for a window shade
16 for a window opening 12 comprising:
(a) a control housing disposed at one end of the window shade 18 and the
window
frame 14 to define a gap there between;
(b) a first cavity presented by the control housing;
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(c) a sprocket wheel 110 within said first cavity 112 for moving the window
blind 16;
(d) an endless blind control element 20 engagable with the sprocket wheel
110;
(e) a channel 86 defining an upper end 82 and a lower end 84 with the
endless loop
blind control element 20 contained within the channel 86 from the upper end 82
to the lower end 84;
(f) a connector 90 supporting the upper end 82 of the channel 86 to the
blind
operating mechanism 118 and depending downwardly from it; and
(g) a tensioning device 30 at the lower end of the enclosure 80 for
tensioning the
endless loop control element 20.
The blind operating mechanism 18 for the window shade 16 using the sprocket
wheel 110
defines a narrow profile whereby the gap is between 4-8 millimetres and the
endless loop
control blind control element 20 is contained out of reach by children.
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