[0001] The present invention relates to a retractable covering for architectural openings,
having primary and secondary retraction mechanisms.
[0002] Architectural coverings with primary and secondary lift mechanisms are known in the
art. Such architectural coverings are generally intended for escape openings in building
structures. The secondary lift mechanism thereby provides an emergency drive that
is preferably automatically activated in emergency situations such as in case of a
fire. Such a secondary lift mechanism is known from German patent reference
DE 3238437, which uses a spring motor to wind a separate lift tape for raising its bottom rail.
When the secondary lift mechanism operates the separate lift tape, the regular lift
tape of the primary lift mechanism will be gathered in an uncontrolled manner between
the slats of the blind. This may inhibit or distort subsequent operation of the primary
lift system. European patent reference
EP 1681435 also discloses the use of a spring drive for a secondary lift mechanism. Again the
secondary lift mechanism uses lift tapes that are separate from the lift tapes for
the primary operating mechanism. This results in a similar drawback of the primary
lift tapes of being gathered in an uncontrolled fashion.
[0003] Accordingly it is an object of the present invention to overcome or ameliorate at
least one of the disadvantages of the prior art. It is also an object of the present
invention to provide alternative structures which are less cumbersome in assembly
and operation and which moreover can be made relatively inexpensively. Alternatively
it is an object of the invention to at least provide the public with a useful choice.
[0004] To this end the invention provides a retractable covering device for architectural
openings, that includes a collapsible covering member; a bottom bar, positioned along
a first edge of the collapsible covering member; at least one flexible element in
engagement with the bottom bar for raising the bottom bar and collapsing the covering
member to define a retracted position of the covering; a primary retraction mechanism
for retracting a first end of the at least one flexible element; and a secondary retraction
mechanism operatively connected with the bottom bar for selectively also retracting
the covering member, wherein the secondary retraction mechanism is arranged for retracting
a second end of the at least one flexible element. The arrangement of sharing one
and the same flexible element between two independent retraction mechanism solves
one of the major inconveniences of the prior art.
[0005] One advantageous embodiment of the retractable covering device according to the invention
further comprises a head rail on a second edge of the covering member opposite the
bottom rail, and wherein both the first and secondary retraction mechanisms are associated
with the head rail. This makes for a compact arrangement of the retractable covering
device with both retraction mechanisms concentrated on one side of the blind and thereby
enabling the bottom rail having the least obtrusive contours. In this regard it is
further advantageous when the bottom rail is provided with at least one guide element
and wherein the at least one flexible element is looped around the at least one guide
element to define a first branch extending from the head rail to the at least one
guide element and a second branch extending from the at least one guide element to
the head rail and parallel to the first branch of the at least one flexible element.
In a further advantageous embodiment of the invention the primary retraction mechanism
has a first axis of rotation and the secondary retraction mechanism has a second axis
of rotation and the second axis of rotation therein is parallel to the first axis
of rotation. Thereby it is further advantageous when a first plane is defined that
is common to the first and second axes of rotation, which first plane is perpendicular
to a second plane that is common to the head and bottom rails in an extended position
of the collapsible covering member. These optional features will make it possible
to also fit the retractable covering device according to the invention in spaces into
which otherwise only conventional retractable covering device would fit.
[0006] Generally it is also advantageous for the retractable covering device according to
the invention when the secondary retraction mechanism includes a spring motor. This
type of drive can be pretensioned to provide for a rapid operation in case of an emergency.
[0007] Still further advantageous embodiment will become apparent from the following description
and appended claims.
[0008] The invention will now be explained in reference to the accompanying drawings, in
which:
- Figure 1 is a compound perspective, sectioned view of a retractable covering device
according to the invention, in which section [A] corresponds to a version using a
first type of side guiding and section [B] corresponds to a version using a second
type of side guiding;
- Figure 2 is an elevation of the compound sectioned view of Figure 1 in the direction
of arrows II-II;
- Figure 3 is a cross-sectional view taken along the line III-III in Figure 2; and
- Figure 4 is a cross-sectional view taken along the line IV-IV in Figure 2.
[0009] In Figure 1, the reference numerals 1A and 1B generally indicate two slightly different
versions of a Venetian blind incorporating the invention. The left hand portion (Figure
1 [A]) illustrates a Venetian blind 1A, that includes a head rail 3, a collapsible
covering member comprising a plurality of slats 5 and a bottom rail 7. The slats 5
are each supported by a flexible ladder support 9 as is conventional with Venetian
blinds. The slats 5 of the blind 1A are each guided and retained in vertical alignment
by a side guiding arrangement using a rod or tensioned cable 11 extending through
apertures 13 at the longitudinal ends of the slats 5. Similarly, the right hand portion
(Figure 1 [B]) represents a portion or a Venetian blind 1B, having a head rail 3,
slats 5 and a bottom rail 7. The slats 5 are each supported by a flexible ladder support
9 and as such the right hand section of version [B] would be similar to a right-hand
portion of the left-hand section of version [A]. The difference is that version [B]
has a channel shaped side guide rail 15 in which slat guiding pins (not shown, but
conventional) ride along the guide rail 15. Such guiding pins may be attached in the
apertures 13 and extend from the longitudinal end of a relevant slat 5. The skilled
person will be familiar with the exchangeability of the side guiding details and will
easily conceive the execution of the right-hand portion of blind version [A] or the
left-hand portion of blind version [B]. Of the lowest slat 5 in Figure 1, only the
contours are shown to reveal more detail of the bottom rail 7.
[0010] Also visible in Figure 1 is that the blind 1A, 1B has openings 17 in the slats 5
for the passage of flexible elements 19 for raising the bottom rail 7 and collapsing
the slats 5 and ladder supports 9 against the head rail 3 to retract the Venetian
blind 1A, 1B. The bottom rail 7 is further provided with guide elements 21, which
are associated with each support ladder 9 for a purpose to be described herein below.
Associated with the head rail 3 is a primary retraction mechanism 23 and a secondary
retraction mechanism 25. The primary retraction mechanism 23 is preferably a conventional
motorized mechanism for raising and lowering a window covering that is controlled
by a conventional electric switch or remote control unit (not shoiwn).
[0011] In Figure 2, a rear elevation of the blind of Figure 1, the same components are referenced
by the same reference numerals. The longitudinal ends of the head rail 3 are connected
with a respective first end bracket 27 and second end bracket 29. The first and second
end brackets 27, 29 are fixedly attached to the respective longitudinal ends of the
head rail 3 and each are adapted to carry one end of the secondary retraction mechanism
25, which is in the form of a spring motor roller having mounted thereon a first an
a second rotatable secondary winding reel 31,33. The elongated spring roller motor
of the secondary retraction mechanism 25 is arranged in parallel relationship with
the head rail 3. The first and second end brackets 27, 29 are each provided with a
relevant first and second mounting flange 35, 37. When a cable or rod side guiding
11 is provided, this can also be attached to the end bracket 27 or 29 by means of
an anchor strip 39. Also attached to the head rail 3 are a first pair of spaced arms
41 and a second pair of spaced arms 43. The first and second pair of arms each form
a cradle for rotatably supporting a relevant first and second guiding rollers 45,
47 and first and second deflection pins 49, 51 (see Figures 3 and 4) for a purpose
to be described.
[0012] Figure 3 is a cross-section taken along the line III-III in Figure 2. The flexible
lift element 19 has a first branch 19A extending downwardly from the primary retraction
mechanism 23, over the deflection pin 51 (or the similar deflection pin 49 as the
case may be), towards a return roller 53 in the guide element 21. The primary retraction
mechanism 23 is provided with a rotatable primary winding reel 55 onto, or from, which
a first end of the flexible element 19 can be wound or unwound as desired. From the
return roller 53 a second branch 19B of the flexible element 19 extends upwardly to
the second guide roller 47 (or the first guide roller 45 as the case may be) to have
its second end wound by the second secondary winding reel 33 (or first secondary winding
reel 31 as the case may be).
[0013] The reference "P" in Figures 3 and 4 denotes an exemplary guiding pin for use with
a side guiding rail (reference "15" as indicated in Figures 1 and 2). Figure 4, which
is a cross-section along the lines IV-IV of Figure 2, shows in more detail one of
the ladder supports 9. Each ladder support 9 has a first branch 9A and a second branch
9B which both extend from a tilt mechanism associated with the primary retraction
mechanism 23. This tilt mechanism is not shown, but is conventional for combined mono-commando
type tilting and lifting mechanisms with which the skilled person is familiar. In
the present context a detailed description of such devices is thus deemed redundant.
The first branch 9A of the ladder support 9 is deflected towards a plane in which
the flexible element 19 extends downwardly towards the guide element 21 on the bottom
rail 7. The first branch 9A is connected to a second branch 9B which extends upwardly
from the guide element 21 along opposite edges of slats 5, back to the tilting mechanism
associated with the primary retraction mechanism 23. The interconnected first and
second branches enable the ladder support 9 to extend through a funnel through the
guide element 21 and to effect tilting of the slats without altering the position
of the bottom rail 7. The first and second branches 9A, 9B are each connected with
opposite ones of the longitudinal edges of slats 5 at points 59A and 59B. This interconnection
can be accomplished by any suitable conventional means as known to the skilled person.
It is also possible to support the slats 5 between cross-rungs, extending between
points 59A and 59B of the first and second branches of the ladder support 9. Also
this system is well known to the skilled person and will not require any further explanation.
[0014] The operation of the retractable covering device as described in relation to Figures
1 to 4 is as follows. Each of the primary and secondary retraction mechanisms 23,
25 are adapted to raise the bottom rail 7 by winding a relevant first or second end
of the flexible element 19. When the primary retraction mechanism 23 lifts the bottom
rail, it will be lifted with half the speed at which the first branch 19A of the flexible
element is wound. This will basically reduce the force required to raise a relatively
heavy blind, which may be an advantage to the general applicability of the primary
retraction mechanism 23. The further advantage obtained is that there will be no flexible
lift element of the secondary retraction mechanism that is compromised or distorted
by the lifting action of the primary retraction mechanism. Conversely also the secondary
retraction mechanism 25 may lift the bottom rail 7 through winding of the second branch
19B of the flexible element 19 in case of an emergency. Again this action will not
compromise or interfere with the operation of the primary retraction mechanism 23.
To achieve this, the secondary retraction mechanism 25 may be provided with a very
strong spring motor which may actually accelerate the movement of bottom rail 7 towards
the head rail 3. Thereby the flexible covering member formed by the slats 5 and the
ladder supports 9 is collapsed between the bottom rail 7 and the head rail 3. To achieve
a quick operation of the secondary retraction mechanism 25, the head rail 3 can be
provided with an operation device 61 (see Figure 1) that is adapted to withdraw a
latch 63 from a circumferential cavity 65 provided in a collar 67 of the secondary
retraction mechanism 25 (Figures 1 and 4).
[0015] The operation device 61 can be remotely controlled by a fire alarm or may be a mechanical
device that is responsive to temperature or smoke conditions that can be associated
with a fire in a building. Also the operation device can be manually controlled from
a button or handle in the close proximity of the escape opening with which the blind
is associated. The skilled person will generally be familiar with other suitable mechanisms
for withdrawal of the latch 63 that are both effective and compliant with the applicable
regulations.
[0016] It is thus believed that the operation and construction of the present invention
will be apparent from the foregoing description and accompanying drawing figures.
The invention is not limited to any embodiment herein described and, within the purview
of the skilled person; modifications are possible which should be considered within
the scope of the appended claims. Equally all kinematical inversions are considered
inherently disclosed and to be within the scope of the present invention. The term
comprising when used in this description or the appended claims should not be construed
in an exclusive or exhaustive sense but rather in an inclusive sense. Expressions
such as: "means for ..." should be read as: "component configured for ..." or "member
constructed to ..." and should be construed to include equivalents for the structures
disclosed. The use of expressions like: "critical", "preferred", "especially preferred"
etc. is not intended to limit the invention. Features which are not specifically or
explicitly described or claimed may be additionally included in the structure according
to the present invention without deviating from its scope.
1. Retractable covering device for architectural openings, including:
a collapsible covering member;
a bottom bar, positioned along a first edge of the collapsible covering member;
at least one flexible element in engagement with the bottom bar for raising the bottom
bar and collapsing the covering member to define a retracted position of the covering;
a primary retraction mechanism for retracting a first end of the at least one flexible
element; and
a secondary retraction mechanism operatively connected with the bottom bar for selectively
also retracting the covering member,
wherein the secondary retraction mechanism is arranged for retracting a second end
of the at least one flexible element.
2. Retractable covering device according to claim 1, wherein the collapsible covering
member includes a plurality of elongate slats, kept in a mutually parallel and spaced
arrangement by at least two flexible suspension ladders, which are spaced from one
another along the length of the slats.
3. Retractable covering device according to claim 1 or 2, further comprising a head rail
on a second edge of the covering member opposite the bottom rail, and
wherein both the first and secondary retraction mechanisms are associated with the
head rail.
4. Retractable covering device according to claim 3, wherein the bottom rail is provided
with at least one guide element and wherein the at least one flexible element is looped
around the at least one guide element to define a first branch extending from the
head rail to the at least one guide element and a second branch extending from the
at least one guide element to the head rail and parallel to the first branch of the
at least one flexible element.
5. Retractable covering device according to one of claims 1 to 4, wherein the secondary
retraction mechanism includes a spring motor.
6. Retractable covering device according to one of claims 1 to 5, wherein the at least
one flexible element is a lift tape and retraction of the covering member can be accomplished
by lifting of the bottom rail.
7. Retractable covering device according to one of claims 1 to 6, wherein the primary
retraction mechanism includes at least one rotatable primary winding reel to which
the first end of the at least one flexible element is attached.
8. Retractable covering device according to one of claims 1 to 7, wherein the secondary
retraction mechanism includes at least one rotatable secondary winding reel to which
the second end of the at least one flexible element is attached.
9. Retractable covering device according to one of claims 1 to 8, wherein the primary
retraction mechanism has a first axis of rotation and the secondary retraction mechanism
has a second axis of rotation and wherein the second axis of rotation is parallel
to the first axis of rotation.
10. Retractable covering device according to claim 9, wherein a first plane is defined
that is common to the first and second axes of rotation, which first plane is perpendicular
to a second plane that is common to the head and bottom rails in an extended position
of the collapsible covering member.
11. Retractable covering device according to claim 10, wherein the at least one flexible
element extends in a third plane that intersects the first plane common to the first
and second axes of rotation substantially between the first and second axes of rotation.
12. Retractable covering device according to claim 11, wherein the third plane is co-extensive
with the second plane and wherein the at least one flexible element is deflected from
to primary retraction mechanism towards the second plane by a first guide means and
from the secondary retraction mechanism towards the second plane by a second guide
means.
13. Retractable covering device according to claim 12, wherein the first guide means is
a deflection pin and wherein the second guide means is a guiding roller.