WO2001012944A1

WO2001012944A1 - Lock mechanism for blinds

Info

Publication number: WO2001012944A1
Application number: PCT/IL2000/000478
Authority: WO
Inventors: Jack Ohayon; Ruth Hirsch
Original assignee: G.H.R.D.N. Marketing & Management Ltd.
Priority date: 1999-08-17
Filing date: 2000-08-07
Publication date: 2001-02-22
Also published as: IL131430A0; AU6313300A

Abstract

A lock mechanism for a roller blind deployed for selectively obstructing an opening, the roller blind (10) having, a pair of tracks (12) deployed along opposite edges of the opening, a spindle (14) located in a cavity above the opening, a rolling mechanism (16) for turning the spindle, and a number of interconnected slats (18) associated with the spindle and configured to be slidably engaged with the pair of tracks such that rotation of the spindle in a first sense to a fully-lowered position causes the plurality of interconnected slats to slide along the tracks to a closed position obstructing the opening, and rotation of the spindle in a second opposite sense causes the plurality of slats to be rolled around the spindle within the cavity. The locking mechanism includes one or more locking elements (26) associated with one of the interconnecting slats, the locking element being deployable between a projecting state in which part of the locking element engages a corresponding recess (28) in one of the tracks and a retracted state in which the locking element clears the track so as to allow sliding of the interconnected slats relative to the tracks. The locking element also includes a deployment-and-retraction mechanism.

Description

LOCK MECHANISM FOR BLINDS

FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to reliable blinds constructed from

interconnected slats and, in particular, it concerns a lock mechanism for such

blinds.

It is known to provide blinds constructed from interconnected slats

which, in their closed position, are lowered along tracks positioned at the sides

of an opening such as a window or door and, in their open position, are rolled

around a spindle located in a cavity above the opening. For domestic

applications, the slats are commonly made from polymer materials while partly

or wholly metallic constructions may be preferred for larger or higher-security

applications. Raising and lowering of the blind is typically performed either

manually or electrically. All such blinds will be referred to herein generically

as "roller blinds".

The security offered by roller blinds may be enhanced by use of a lock

to prevent opening of the blind. The simplest and most common

implementation of such a lock is a simple bolt slidably mounted within one of

the slats which can be slid into engagement with a recess formed in a

corresponding part of the track.

Locks of this type suffer from a number of disadvantages. Firstly, since

the lock is actuated independently from the closing action of the blinds, the

user may forget altogether to actuate the lock, leaving the blind in a low

security state. Additionally, in the case of electrically operated blinds, damage may be caused to the blinds, lock or motor if the opening mechanism is

inadvertently operated without first releasing the lock.

There is therefore a need for a lock mechanism and corresponding

method which would lock a roller blind when closed without requiring

independent actuation of a lock and which would unlock it as an initial part of

the normal opening operation.

SUMMARY OF THE INVENTION

The present invention is a lock mechanism for roller blinds, and a

corresponding method.

According to the teachings of the present invention there is provided, a

lock mechanism for a roller blind deployed for selectively obstructing an

opening, the roller blind having: a pair of tracks deployed along opposite edges

of the opening; a spindle located in a cavity above the opening; a rolling

mechanism for turning the spindle; and a plurality of interconnected slats

associated with the spindle and configured to be slidably engaged with the pair

of tracks such that rotation of the spindle in a first sense to a fully-lowered

position causes the plurality of interconnected slats to slide along the tracks to a

closed position obstructing the opening, and rotation of the spindle in a second

opposite sense causes the plurality of slats to be rolled around the spindle

within the cavity, the lock mechanism comprising: (a) at least one locking

element associated with one of the interconnected slats, the locking element

being deployable between a projecting state in which at least part of the locking element engages a corresponding recess in one of the tracks and a retracted

state in which the locking element clears the track so as to allow sliding of the

interconnected slats relative to the tracks; and (b) a deployment-and-retraction

mechanism associated with the at least one locking element and with the

spindle, the deployment-and-retraction mechanism being responsive to rotation

of the spindle to its fully-lowered position to deploy the at least one locking

element to the projecting position so as to lock the blind, the

deployment-and-retraction mechanism being further responsive to rotation of

the spindle from its fully-lowered position to retract the at least one locking

element to the retracted position so as to unlock the blind.

According to a further feature of the present invention, the

deployment-and-retraction mechanism includes: (a) a biasing element

associated with the locking mechanism and the at least one slat, the biasing

element being configured to bias the locking element to the projecting state;

and (b) a retraction mechanism associated with the locking element and the

spindle, the retraction mechanism being responsive to rotation of the spindle in

the second sense to withdraw the locking element to the retracted state against

the biasing element.

According to a further feature of the present invention, the retraction

mechanism includes at least one draw-cable connecting between the locking

element and the spindle.

There is also provided, according to the teachings of the present

invention, a method of locking a roller blind deployed for selectively obstructing an opening, the roller blind having: a pair of tracks deployed along

opposite edges of the opening; a spindle located in a cavity above the opening;

a rolling mechanism for turning the spindle; and a plurality of interconnected

slats associated with the spindle and configured to be slidably engaged with the

pair of tracks such that rotation of the spindle in a first sense to a fully-lowered

opposite sense causes the plurality of slats to be rolled around the spindle

within the cavity, the method comprising, providing a lock mechanism

mechanically linked to the spindle such that the lock mechanism is deployed by

lowering of the blind to its full extent to lock the blind against opening and is

unlocked by rotation of the spindle in its second sense.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, with

reference to the accompanying drawings, wherein:

FIG. 1 is a schematic representation of a roller blind fitted with a lock

mechanism constructed and operative according to the teachings of the present

invention;

FIG. 2 is a partial, cut-away isometric view showing part of the lock

mechanism of Figure 1; and

FIGS. 3A-3C show schematically three points during the operation of

the roller blind of Figure 1. DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is a lock mechanism for roller blinds, and a

corresponding method.

The principles and operation of lock mechanisms according to the

present invention may be better understood with reference to the drawings and

the accompanying description.

Referring now to the drawings, Figures 1-3 illustrate a lock mechanism,

constructed and operative according to the teachings of the present invention,

deployed within a roller blind 10 which is deployed for selectively obstructing

an opening (not shown).

Before addressing the lock mechanism of the present invention, the

structure and operation of roller blind 10 will first be described. It should be

noted however that the description of roller blind 10 is given here to facilitate

understanding of the lock mechanism of the present invention, but that the

blind does not per se constitute part of the present invention. The description of

roller blind 10 given here should therefore be understood as exemplary of the

class of blinds to which the invention applies, and should not be considered

limiting.

Roller blind 10 has a pair of tracks 12 deployed along opposite edges of

the opening, and a spindle 14 located in a cavity above the opening. A rolling

mechanism, represented here schematically by a drive belt 16 is deployed for

turning spindle 14. A number of interconnected slats 18 are associated with

spindle 14, typically suspended by straps 20. Interconnected slats 18 are configured to be slidably engaged with tracks 12. Normal operation of roller

blind occurs by rotating spindle 14 in a first sense 22 to a fully-lowered

position which causes interconnected slats 18 to slide along tracks 12 to a

closed position obstructing the opening (Figures 1 and 3C), and by rotating

spindle 14 in a second opposite sense 24 which causes interconnected slats 18

to be rolled around spindle 14 within the cavity (Figure 3A), thereby

uncovering the opening.

Turning now to the lock mechanism itself, this includes at least one, and

preferably at least two, locking elements 26 associated with one of

interconnected slats 18. Each locking element 26 is deployable between a

projecting state (Figures 1, 2 and 3C) in which at least part of locking element

26 engages a corresponding recess 28 in one of tracks 12 and a retracted state

(Figure 3B) in which locking element 26 clears track 12 so as to allow sliding

of interconnected slats 18 relative to tracks 12. In the preferred example

illustrated here, locking elements 26 are implemented as bolts slidably mounted

within a cylindrical housing 27.

The lock mechanism also includes a deployment-and-retraction

mechanism associated with the at least one locking element 26 and with spindle

14. The deployment-and-retraction mechanism is responsive to rotation of

spindle 14 in first sense 22 to its fully-lowered position to deploy the at least

one locking element 26 to the projecting position so as to lock the blind. The

deployment-and-retraction mechanism is also responsive to rotation of spindle 14 from its fully-lowered position in second sense 24 to retract the at least one

locking element 26 to its retracted position so as to unlock the blind.

At this stage, it will be clearly understood that the lock mechanism of

the present invention provides a convenient and elegant solution to the

above-mentioned problems of the prior art. Specifically, the locking element is

deployed automatically as a continuation of the normal operation of lowering

the blind without requiring the user to remember to actuate a lock. Once in the

locked state, the locking element provides effective security against

unauthorized manual raising of the blind from outside. The mechanism then

automatically unlocks itself at the beginning of the normal opening operation,

rendering the blind convenient for manual operation and avoiding the damage

caused by operation of electric actuation systems when locked.

Turning now to the features of the lock mechanism in more detail, it is

generally preferred to deploy locking elements 26 symmetrically in pairs at

opposite ends of a slat 18. In the preferred case illustrated here, two locking

elements 26 are deployed at the ends of the uppermost slat 18 that enters tracks

12. Additionally, or alternatively, locking elements 26 may be deployed in

lower slats, at the lower edge of the blind or in an intermediate position.

The deployment-and-retraction mechanism may be implemented in a

wide range of forms which perform the function stated above. In a particularly

effective and simple implementation shown here, the

deployment-and-retraction mechanism includes a biasing element 30 associated

with each locking element 26 and the at least one slat 18, and configured to bias locking element 26 to its projecting state. A retraction mechanism,

preferably implemented as a draw-cable 32 connecting between each locking

element 26 and spindle 14, is responsive to rotation of spindle 14 in second

sense 24 to withdraw locking element 26 to its retracted state against biasing

element 30. Optionally, a single retraction mechanism may be used to operate

two or more locking elements 26. Additionally, the retraction mechanism may

be implemented without the use of separate draw-cables through a mechanical

linkage operated by tension in straps 20.

Where one or more draw-cable 32 is used, the required sequence of

closing followed by locking and unlocking followed by opening is typically

ensured by the relative tensioning and length of straps 20 and draw cables 32.

Specifically, straps 20 should be sufficiently long to hang slightly loose in the

fully-lowered and locked state of Figure 3C while being just-taut when locking

elements 26 reach their fully retracted position of Figure 3B. It should be

noted, however, that these conditions are not always necessary. For example, in

many roller blinds, slats 18 are interconnected by links which allow a slight

spacing to open up between adjacent slats when raised, the spacing closing up

when the blind is lowered. In such a case, if locking element 26 is deployed at a

lower position in blind 10, the opening and closing of spaces between slats

inherently provides the required changes in tension in draw-cables 32.

It will be clear that the present invention also provides a method of

locking a roller blind of the type described above, by providing a lock

mechanism mechanically linked to the spindle such that the lock mechanism is deployed by lowering of the blind to its full extent to lock the blind against

opening and is unlocked by rotation of the spindle in its second sense.

It will be appreciated that the above descriptions are intended only to

serve as examples, and that many other embodiments are possible within the

spirit and the scope of the present invention.

Claims

WHAT IS CLAIMED IS:

1. A lock mechanism for a roller blind deployed for selectively

obstructing an opening, the roller blind having:

a pair of tracks deployed along opposite edges of the opening;

a spindle located in a cavity above the opening;

a rolling mechanism for turning the spindle; and

a plurality of interconnected slats associated with the spindle and

configured to be slidably engaged with the pair of tracks such that

rotation of the spindle in a first sense to a fully-lowered position

causes the plurality of interconnected slats to slide along the

tracks to a closed position obstructing the opening, and rotation

of the spindle in a second opposite sense causes the plurality of

slats to be rolled around the spindle within the cavity,

the lock mechanism comprising:

(i) at least one locking element associated with one of the

interconnected slats, said locking element being deployable

between a projecting state in which at least part of the locking

element engages a corresponding recess in one of the tracks and a

retracted state in which said locking element clears said track so

as to allow sliding of the interconnected slats relative to the

tracks; and

(ii) a deployment-and-retraction mechanism associated with said at

least one locking element and with the spindle, said deployment-and-retraction mechanism being responsive to

rotation of the spindle to its fully-lowered position to deploy said

at least one locking element to said projecting position so as to

lock the blind, said deployment-and-retraction mechanism being

further responsive to rotation of the spindle from its fully-lowered

position to retract said at least one locking element to said

retracted position so as to unlock the blind.

2. The lock mechanism of claim 1, wherein said

deployment-and-retraction mechanism includes:

(i) a biasing element associated with said locking mechanism and

the at least one slat, said biasing element being configured to bias

said locking element to said projecting state; and

(ii) a retraction mechanism associated with said locking element and

the spindle, said retraction mechanism being responsive to

rotation of the spindle in the second sense to withdraw said

locking element to said retracted state against said biasing

element.

3. The lock mechanism of claim 2, wherein said retraction

mechanism includes at least one draw-cable connecting between said locking