GB2257470A

GB2257470A - "screen"

Info

Publication number: GB2257470A
Application number: GB9212415A
Authority: GB
Inventors: Thomas John Scott Tidmarsh; John Stewart Jackson
Original assignee: TIDMARSH ESTATE Ltd
Current assignee: TIDMARSH ESTATE Ltd
Priority date: 1991-06-13
Filing date: 1992-06-11
Publication date: 1993-01-13
Also published as: AU1896792A; GB9112683D0; WO1992022724A1; GB9212415D0

Abstract

A screening device (1) for use in banks or building societies is provided where a flexible screen (7) can be moved across a window (5) which is located above a counter (4) to obscure the view through the window (5) and thereby break visual contact between the cashier on one side of the window (5) and a gunman on the other side of the window (5). The movement of the flexible screen is rapid and is triggered by the provision of an electrical alarm signal. The leading edge of the screen (7) is provided with a rail (11), itself having a leading edge covered with a strip of padding (13) to prevent injury to a cashier's hand if positioned below the rail (11). The rail (11) is made heavy so that it descends under the force of gravity. The screen is dispensed from a first roller (9) which is biased to wind the screen (7) onto itself but the biasing force of the roller (9) is less than the force exerted on the rail (11) by gravity so that on activation of a release mechanism the rail (11) and screen (7) descend rapidly down across the window.

Description

.q CR E < N The present invention relates to a screening device that is provided with a screen whose movement can be triggered by an alarm signal. The screening device finds particular use in conjunction with counters and cash desks where a window is located above the counter or cash desk. The screen may break visual contact between a cashier on one side of the counter and an armed robber on the other side.

Generally the arrangement of cash desks in banks and building societies consists of a desk or counter above which is located a window. The window is usually a panel of bullet resistant glass. Usually a cashier will be on one side of the window where money is kept. Public access is allowed to the other side of the window.

During a robbery a gunman or robber will be on the public side of the window and the cashier will often only have the bullet resistant window between himself and the armed robber. From the cashier's point of view, experiencing an armed robbery is a particularly distressing experience and can have lasting psychological effects even after the robbery has finished. The fact that the cashier will usually see a firearm, which is being pointed towards the cashier through the window, only serves to increase the distress.

Previous attempts have been made to provide apparatus capable of effecting an instant and complete break in communication between the cashier and the gunman. One such apparatus consists of an "open" type counter (that is to say, one that is not provided with a window) where, upon activation of an alarm signal, a solid plate is moved rapidly and upwardly from below the counter. This plate is usually made of metal, and is bullet resistant, and under normal circumstances is concealed below the counter. The plate, on activation, thus provides a physical barrier, and prevents audio and visual communication between the gunman and cashier. The break in communications may serve to reduce the possibility of the gunman taking a hostage on the public side and using him or her to bargain for any money or valuables.

An alternative similar "open" type apparatus is additionally provided with two relatively slidable panels on the public side of the counter. The top of a solid plate is hinged so that on upward movement of the plate the panel performs a tilt and slide motion. The panels tilt towards the gunman to provide a physical barrier between the gunman and cashier.

There are several disadvantages with these systems.

Firstly, both are usually installed at the same time as when the counter or desk itself is installed. Although alteration of existing counters or desks is not impossible, a considerable amount of modification would be required. In fact, the amount of work required makes alteration of existing counters or desks impractical and prohibitively expensive. Thus both systems will usually be installed when the counter or desk is being built and cannot be practically installed to an existing counter or desk. Furthermore, due to their complexity and the nature of installation both systems require a considerable cost outlay.

Secondly, many counters or desks are provided with a bullet resistant window and so the fact that these two systems are only suitable for "open" type counters is a considerable disadvantage.

In addition, the second system described above, with the tilting desktop, is not suitable where items and apparatus (such as computers, terminals and printers) are situated on the desktop.

There is therefore a need to provide a relatively simple apparatus that can not only break visual contact between the gunman and the cashier but that can be quickly and rapidly deployed so that the gunman has little time to react.

Thus according to a first aspect of the present invention there is provided a screening device comprising a counter above which is located a window, and a flexible screen which can be moved across the window to obscure at least part of the field of view through the window, the movement of the screen capable of being triggered on provision of an alarm signal.

By providing a flexible screen, the screen can be rapidly and quickly deployed, allowing a gunman little time to react. Indeed, the screen in the present invention is preferably moved across the window at such a speed that the gunman will not have sufficient time to discharge any firearm he or she is carrying. The screen may thus effect a break in visual contact and communication between the cashier and the gunman which can considerably decrease the distress experienced by a cashier during an armed robbery. Furthermore, the gunman, realising he has lost visual (and probably also audio) contact with the cashier, tends to view this as removal of any control he or she may have had, and can psychologically lower any expectations of receiving money or valuables on demand or threats.

In addition, the screening device of the present invention can be used in conjunction with existing counters that are provided with windows, so that they can be installed after installation of the counter. This means that the screening device is less expensive to install.

It will be appreciated that the screening device encompasses arrangements where a plurality of counters and/or a plurality of screens are provided. Thus a single counter may be provided with a plurality of screens, and in this case it is preferred that all of the screens can be triggered simultaneously, so that they suitably all move across an (e.g. respective) window in unison. However, a plurality of counters may be provided, for example staggered with respect to each other, in which case each counter may have a respective screen.

The screening device can be relatively simple in construction, allowing for easy installation, and with few moving parts can be reliable, which is clearly a desirable quality. Cashiers can benefit from peace of mind knowing that the screening device will operate once the alarm signal has been provided, and indeed it is likely that the screening device will be tested at least once every working day, usually before opening hours, as a check to ensure that the screening device is operating correctly.

Here the term "window" is intended to encompass an optically transparent panel that is often provided above the counter and which is usually resistant to attack by the discharge of a firearm or by the use of other offensive weapons. Although the bottom of the window need not necessarily be in contact with a top of the counter, it is preferred that this is the case so that it may provide the cashier with maximum protection against any gun fire. If a tray or well is provided in the counter top (to allow passage of money and/or valuables) then this is also preferably constructed to provide protection against any gun fire.

The window suitably comprises glass and/or transparent polymeric material, eg perspex. Preferably the window will be a laminate structure. In this case, a glass layer will suitably be provided on either side of the window, so 'sandwiching' any other layer or layers.

It will thus be appreciated that there are two separate sides of the screening device, one on either side of the window (or counter). On one side, which shall be called the cashier's side, a cashier, member of staff or employee (the terms are used interchangeably) of, for example, a bank or building society, will be present. The cashier's side will thus be the side on which cash, jewellery or other valuables will usually be kept, collected or dispensed from.

The other side of the window can be termed the gunman's side. This side of the window is accessible by the public, which will usually be customers and/or clients.

Although reference is made to a gunman in this specification, it will be realised that this includes thieves, robbers and any person that is intending t^ obtain cash, jewellery or other valuables by means of visual or verbal threats. Thus the gunman may not necessarily be carrying a gun but may be armed with an offensive weapon which he or she is using to obtain the cash, jewellery or other valuables. Indeed, it is not impossible that the gunman may be carrying an object which appears to be a gun or offensive weapon, or an object which the gunman falsely represents as being a gun or offensive weapon.

The screening device of the present invention finds particular use during armed robberies since the flexible screen can be moved rapidly so that the cashier may not see the gunman discharge the firearm towards the cashier.

As has been appreciated, although reference is made to guns and firearms, the gunman may in fact be carrying a fake gun or firearm that cannot be fired. However, the cashier is unlikely to know this.

The term "counter" in this specification encompasses a desk, bar or other items of furniture that acts as a separating barrier between the public or gunman on one side of the window and the cashier on the other side.

The counter need not necessarily be in a bank or building society but may be in a building where any cash, jewellery or other valuables are kept, collected or dispensed. Thus this may include safety deposit houses, ticket offices and casinos.

The screening device is thus intended to substantially reduce, and preferably completely obscure, the field of view through the window. The whole of the window may not necessarily be covered or obscured by the flexible screen, although it will be appreciated that in preferred embodiments the screening device achieves this. Thus, it is preferable that on movement of the flexible screen the field of view through the window is obscured to the extent that the cashier cannot see the gunman on the other side of the window (or vice versa), preferably even if the gunman decides to climb onto the counter itself.

The term "screen" is intended to encompass shutters, sheets, curtains or blinds, all of which are capable of being moved across the window. One of the principal purposes of the flexible screen is to provided visual obscuration. Generally the flexible screen need not be fire resistant, bullet resistant or impenetrable since these characteristics will usually be properties of the window. However, a screen having sound proofing and/or flame retardant or resistant properties may be advantageous in some applications. In some embodiments the screen is preferably impenetrable to flying glass or spalling that may contact the screen after, for example, discharge of a firearm into the window. The flexible screen can thus be made of a lightweight material so that it can be rapidly moved.The screen is therefore preferably made of light metal alloy (e.g. aluminium alloy) or of a non-metallic material. Preferred nonmetallic materials include textile materials, fabrics or a plastics material (such as in the form of a sheet).

Indeed, some of these materials may be combined, for example a fabric material (eg a polymer, such as polyester) having a metallic layer (eg aluminium).

Thus the term "flexible", when used in conjunction with the screen, encompasses screens that can be bent, flexed or curled but does not include solid inflexible panels.

However, the invention does contemplate screens that can be folded, pleated or corrugated, such as shutters (which may comprise a plurality of jointed stripsj that may be in a folded (e.g. like a concertina) state before movement across the window. The screen may thus provide a degree of audio isolation, as well as visually, especially if it is constructed of metal. Preferably the screen will be adapted so that it can be dispensed from a roller and/or dispensed in the form of a roll.

The screen will preferably be provided with writing on one or both sides, which will usually be printed. Thus the screen may carry a warning, instructions, or other information to the gunman and/or the cashier. On the gunman's side of the screen, this may be to the effect that an alarm has been raised and that the cashier can not communicate (visually or audibly) with the gunman and/or that the cashier is unable to remove or retract the screen once it has been deployed. On the cashier's side of the screen, there may be provided information to the effect that the cashier is to move away from the window and that the cashier is also unable to (at least initially) remove or retract the screen once it has been deployed.

It will thus be appreciated that the screen will preferably move across the cashier's side of the window.

This can prevent the gunman tampering with the screen.

It is also preferred that the screen moves in a downward direction, since this will be gravity-assisted.

Although it has been stated that the flexible screen can be moved across the window, it is usual that the movement of the screen is in a direction between the cashier and the window so that the f eln ; vie. through the window can be at least partially (although preferably totally) obscured. Thus although the screen preferably moves in a direction parallel to the window, or substantially parallel to the window, it will be appreciated that this is not essential. Nevertheless the direction of travel of the screen will preferably be ln the plane of the window.

The movement of the flexible screen is suitably a sliding motion so that the flexible screen progresses across the window. This may be in any direction, such as upwardly or sideways across the window although a downward motion is preferred. Preferably the screening device will be provided with one or more (suitably vertical) guides, for example channels, to guide the motion of the screen.

The alarm signal is suitably provided by an alarm system.

The signal can be in the form or a hydraulic, pneumatic or any other suitable impulse but will usually be an electrical signal. Such an alarm system is preferably triggered manually by a trigger mechanism. This may be cashier-operated, for example a "panic button" or by means of another suitable mechanisms, such as personal alarm or personal attack buttons, pedals, foot bars or kicks and infra-red (or other light beam) or radio activated devices. For example, such a trigger mechanism may be triggered by the removal of all the bank notes from a compartment or tray.

The screen will generally be biased, via biasing means, in a direction that moves the screen across the window, thereby obscuring at least part of the view therethrough.

The screening device will thus preferably have a release mechanism that is triggered, operable cr activated by the alarm signal (either directly or indirectly). The biasing means will then act, on provision of the alarm signal, to move the screen across the window. The biasing means may comprise one or more individual biasing mechanisms: these may act together, although sometimes it is preferred that they act against each other, in which case one biasing mechanism will have greater force than another to ensure that the screen will still move across the window when desired. In preferred embodiments, two opposing biasing mechanisms may be provided.

The screen may thus be moved either by a suitable (eg mechanical) biasing mechanism, or may simply move (downwardly) under the influence of gravity, or even a combination of both. A gravity system may be cheaper to manufacture and install.

If one is relying on the force of gravity, then the screen needs to be of sufficient weight so that the gravitational force is stronger than any resisting forces, for example frictional forces. Here the screen may include heavier materials and so may include metallic components, for example the screen may be wholly metallic or be provided with metal layers, or may comprise suitably located metal weights.

Of course, if the screen is too heavy, then despite the advantage of relatively quick (downward) motion, it may become difficult to raise the screen after deployment.

Thus, in some embodiments it is preferable to additionally bias the screen against movement across the window, such as with a biasing mechanism. Clearly such a bias will not prevent such motion, but may merely assist in retraction of the screen. Thus. the screen will still, effectively, be biassed towards moving across the window, by the biasing means which will usually occur on provision of the alarm signal.

While a single biasing means may serve to move the screen (for example, the biasing mechanism may simply be weights or a spring-loaded roller), better results have been achieved by using more than one biasing mechanism, and in particular two. Preferably these biasing mechanisms oppose each other.

Thus, while the invention includes a single biasing mechanism, two preferred embodiments have the following constructions. Firstly, the biasing means comprises a first biasing mechanism in the form of weights, and a second, opposing, mechanically operated biasing mechanism. The second is that the biasing means comprises two opposing mechanically operated biasing mechanisms.

In preferred embodiments the mechanically operated mechanisms comprise springs. Thus, in the first embodiment, the spring may be wound up, and the torsion increased, when the screen is moved across the window.

This will result in the screen moving quickest on provision of the alarm signal and slowest when the screen has moved across the window. Usually the second biasing mechanism will not prevent the screen from moving or stopping: in any case at this stage the screen may have built up momentum. However, the force of the second biasing mechanism may be such that it balances the force of the weight of the screen (to keep it still) or, when the screen is not in motion, be sufficient to just raise the screen.

The screen may thus be pulled or drawn across the window.

This arrangement may provide the most rapid form of movement of the screen. However, the screen may be suitably weighted so that it will move (such as descend) simply under the influence of gravity, and it will be appreciated that some mechanical assistance may additionally be provided. Thus the screening device can be provided with a biasing mechanism which is biased to move the flexible screen (such as by a pulling or drawing motion) across the window. However, in some embodiments a biasing mechanism may bias the screen in the opposite direction, that is to say to retract the screen so that the screen has a tendency not to obscure the view through the window.In this case, such a biasing mechanism will assist retraction of the screen after deployment, and will usually be included if the movement of the screen across the window is solely due to gravity, or essentially gravity assisted.

The biasing mechanism comprises a spring, such as a torsion spring, or a weight if the screen is to be moved by gravity. The biasing mechanism may thus preferably be provided with a release mechanism, for example a latch.

The release mechanism may thus act to hold the screen in a biased state, or an "active" condition, so that the flexible screen as prevented from moving across the window. Preferably the release mechanism is activated by, or operable by, the alarm signal. Thus, the alarm signal will suitably activate the release mechanism to allow the screen to be pulled or drawn across the window by the biasing mechanism.

Similarly, if the movement of the screen across the window is gravity operated, or substantially gravity assisted, a release mechanism can be provided which, for preference, may also comprise a latch. This will initially hold and prevent the screen moving across the window. Again, the alarm signal will suitably activate the release mechanism, this time allowing the screen to move downwards under the influence of gravity.

Where a (eg second) biasing mechanism is provided that acts against the natural tendency of the screen to move downwards under gravity, it will be apparent that these two forces need to be properly balanced. The screen should have sufficient weight (or momentum) to allow it to obscure partially, and preferably all of, the view through the window despite the opposing force of this biasing mechanism.

The screen, by being flexible, can be folded, curled, wound up or pleated into a compact state (such as in the active condition) from which the screen can be moved across the window once triggered by the alarm signal. In this compact state the screen may occupy a relatively small volume which, unlike prior art solid screen panels, can allow easy installation with an existing counter having a window. The compact state may thus be in the form of a roll or, if the screen is a shutter having a plurality of jointed strips, in the form of folded pleats (such as a concertina fashion).

The flexible screen is thus preferably dispensed from a roll or a rotatable dispensing member. Thus, in the active condition the screen will usually be wound onto the rotatable dispensing member. If the screen is sufficiently rigid (e.g. a shutter), the dispensing member may be constituted by a roll of the flexible screen itself. However. the dispensing member will usually be a roller. In such a compact state the screen may be enclosed within a housing.

The biasing means can thus comprise a first biasing mechanism embodiment and a second biasing mechanism (which may also be in the form of a spring) which acts to wind the flexible screen onto the rotatable dispensing member. In a preferred embodiment the dispensing member is a roller so that the flexible screen and rotatable dispensing member comprise a roller blind. The second biasing mechanism is thus preferably a spring, such as a torsion spring, which may be mounted internally inside the roller (e.g. a helical spring).

It will thus be appreciated that in a preferred embodiment there is a first biasing mechanism (such as one or more weights or a spring) which is biased to pull or draw the screen across the window while a second biasing mechanism acts in the opposite direction, to wind the flexible screen onto the rotatable dispensing member.

So that the flexible screen can be moved across the window it will be appreciated that the first biasing mechanism must have a greater (eg gravitational) force or bias than the second. Thus, under equilibrium conditions the screen will be pulled or drawn across the window by the greater strength of the first biasing mechanism. The first biasing mechanism is preferably a weight (which may be the weight of the screen itself) or a spring and may be the same as the second biasing mechanism, namely a helical spring. This may be provided internally inside a roller. The first and/or second biasing mechanisms may therefore be provided by the roller portion of a roller blind.

By providing opposed first and second biasing mechanisms this may assist in retraction of the screen once it has been moved across the window, but may also help to keep the screen taut during its motion.

In order that the first biasing mechanism can act on the screen, tending it to be drawn or pulled across the window, the first biasing mechanism is suitably connected to the screen, such as to a leading edge of the screen.

This may be done by one or more flexible elongate members. Each elongate member can be a strap, cord, rope, filament, fibre (or group of filaments or fibres), a line, cable, wire or (preferably) a tape. It is preferred that two flexible elongate members are provided, each elongate member being attached to respective ends of a leading edge of the screen. Thus the force of the first biasing mechanism is transmitted along the or each flexible elongate member to pull or draw the screen across the window.

The or each elongate member is preferably attached to an end of a leading edge of the screen. However, it is more preferable that the or each elongate member is attached to a side edge of the screen. This may allow the or each flexible elongate member to be concealed inside a slot (e.g. respective) or channel so that the or each elongate member is not visible from the gunman's side of the window. Each slot or channel may thus serve as the guide for the flexible screen whose side edges can thus extend into a respective slot or channel. This may mean that there is no gap between the (two) side edges of the screen and the respective slot or channel.

Tbe leading edge f I~h.2 CkP screen is preferably provided with a rail. This may serve as a biasing means to assist (downward) movement ot the screen, and so may constitute the first biasing mechanism. The leading edge may also serve to collect the leading edge of the screen to prevent fraying and/or distortion of the screen. In addition it may also provide a point of attachment for the or each flexible elongate member. The rail may be provided, along the rail's leading edge, with a (suitably resiliently) deformable strip which may act as a cushion or padding, for example so that the rail has a soft leading edge. The motion of the screen (and rail if provided) across the window will usually be terminated, or stopped by the top of the counter.The deformable strip may therefore act to cushion the impact of the rail, which will usually be moving at a considerable speed, when it contacts the top of the counter. In addition, the deformable strip may serve to reduce or prevent injury to the cashier should he or she have a part of the body, such as fingers, hand or arm, between the rail and the counter top.

The rail may also be used to attach additional weights, if desired, when it forms part of the biasing means (such as the first biasing mechanism). These may help in quickening the movement of the screen downwardly and may assist in balancing the force of the second biasing mechanism, if provided.

In addition to the movement of the screen being triggered by an alarm signal, the same movement can also preferably be triggered manually, without an alarm signal, as a manual override. This can be useful if the alarm signal, for whatever reason, fails to trigger the motion of the screen. This can be achieved by adapting the release mechanism so that it is also manually operable. In preferred embodiments this mechanism comprises a latch; suitably this latch releases the screen, or the rail or a part of the rail, for example on provision of an electrical (alarm) signal, such as if the release mechanism comprises! or is activated or triggered by, a solenoid.

Thus a latch may be provided on each side of the screen; preferably each latch operates on the rail, for example on a retractable protrusion on (eg each side of) the rail. Such protrusions may be retracted manually to provide the manual override and are preferably biased to protrude, such as by means of one or more springs. The protrusions may be placed on the rail but are suitably housed within the rail. Each protrusion (suitably one at each end of the rail) may form part of a rod whose movement relative to the rod is accomplished by one or more linkages, such movement allowing retraction of the or each protrusion. Such linkage(s) may be joined by pivotable members. A manually operable actuator can be provided (eg on or in the rail) which is adapted to retract the or each protrusion (eg via the pivotable members, linkages and rod movement), thereby disengaging the latch and releasing the screen. The latch can also be disengaged on provision of the alarm signal by an electrical signal that activates a solenoid.

Preferably the screen, once it has been deployed, can be held in a position where it obscures, at least partially, the view through the window, by catch means. Such catch means is, of course, suitably releasable (eg manually) so that the screen can be retracted when necessary. The catch means may be any suitable mechanism to prevent motion of the screen, and to prevent retraction, and may comprise a latch or any means of engaging with a fixed member to prevent movement. Such engagement means may be a protrusion (for example, the protrusions mentioned above for the rail that are preferably retractable), a detent, groove or male or female member that can be provided on the screen (eg on or inside the rail) and/or the counter, window or other suitable rigid part of the screening device (eg guide means, slot channel).

In a preferred embodiment the rail is provided with an espagnolet lock arrangement whereby the movable rods provide the retractable protrusions. The arrangement may be operable by a key, in which case the screen cannot be deployed without the key, but the same key is needed to retract the screen. Alternatively the arrangement is operable by a knob or other manually movable device so that the screen can be operated quickly if the alarm signal fails, but equally allows easier retraction of the screen once fixed by the catch means.

The counter top can be provided with a contoured elongate strip which is angled or contoured so that if an object is caught between the rail and elongate strip the object will be urged in a direction out of the path of the flexible screen, in order to no longer be located between the rail and elongate strip. The elongate strip may thus act to prevent the screen being stopped from fully closing, that is to say, reaching the end of its travel (which will usually be the counter top).

The screening device is preferably provided with a rotatable winding member onto which the or each flexible elongate member can be wound. This can be in the form of a wheel or spool but is preferably a roller. If the winning member 15 s oiler, ten the first biasing mechanism can be an internal torsion (e.g. helical) spring. Here torsion spring means a spring that is capable of developing a torque and transmitting such (for example through a roller) in such a way to cause (e.g.

the roller) to rotate about its longitudinal axis.

Combined with the force of the second biasing mechanism, this results in the flexible screen being kept taut during both the active condition and when the screen is being pulled or drawn across the window. The first biasing mechanism may assist in retraction of the flexible screen when required (by winding the flexible screen onto the rotatable dispensing member).

The screening device is preferably provided with a locking mechanism. This may prevent the screen from being retracted. Here retraction means withdrawal or motion of the screen back across the window so that the field of view through the window is no longer obscured.

The locking mechanism can prevent the cashier from retracting the flexible screen if, for example, the cashier (perhaps erroneously) believes that the robbery has finished and that the gunman is no longer on the other side of the window. The locking mechanism is preferably a ratchet arrangement which allows movement of the screen in only one direction. This direction will be the direction of motion of the screen to obscure the field of view through the window. The ratchet arrangement preferably comprises a pawl which is capable of engaging with teeth on a sprocket wheel (which term encompasses a circular rack). Thus, once the flexible screen has stopped moving across the window, or comes to the end of its travel, the ratchet arrangement of the locking mechanism will prevent retraction of the screen (at least InitIally).

It will of course be realised that at some stage, such as after the robbery has finished, it will be desirable to retract the flexible screen. This can be achieved by allowing the locking mechanism or catch means to be overridden or reset. This can be done by making the ratchet arrangement disengagable by provision of ratchet disengagement means. This is preferably operable manually, and may be achieved by provision of a lever or push-rod. However, the ratchet disengagement means may be operable electrically and may be operable at a place remote from the screen or counter (thus preventing operation by the cashier), for example this may be operable only by a key mechanism which will provide the electrical signal to disengage the ratchet arrangement.

On disengagement of the ratchet arrangement the flexible screen can be retracted and it is preferable that once the screen has been retracted (such as to the compact state) it will be in an active condition ready to be triggered on provision of the alarm signal (such as deployed on activation of the release mechanism).

The release mechanism may comprise a ratchet arrangement.

In common with the preferred form of the locking mechanism, the ratchet arrangement is suitably disengagable and/or may comprise a pawl that is capable of engaging with teeth on a sprocket wheel (which term also encompasses a circular rack). Thus it is preferred that activation of the release mechanism comprises disengagement of the pawl from the teeth on the sprocket wheel, thereby allowing rotation of the rotatable winding member. The rotatable windina member is thus preferably provided with the sprocket wheel.

Preferably both the locking mechanism and release mechanism act on the rotatable winding member, and more preferably on the sprocket wheel of the rotatable winding member. Suitably the release mechanism and locking mechanism co-operate so that in the active condition the release mechanism allows the sprocket wheel (and therefore the rotatable winding member) to be rotated only in one direction (such as to retract the screen) while the locking mechanism acts to allow rotation of the sprocket wheel (therefore rotatable winding member) in the opposite direction (namely movement of the screen across the window). Thus the locking mechanism and release mechanism co-operate so that engagement or disengagement of the ratchet arrangement of one mechanism results in respective disengagement or engagement of the ratchet arrangement of the other mechanism. This will preferably occur simultaneously and is preferably achieved by the ratchet disengagement means.

The locking mechanism and release mechanism may thus comprise two pawls which are both biased towards each other and towards the sprocket wheel. The ratchet disengagement means will thus preferably be capable of engaging one ratchet mechanism while simultaneously disengaging the other ratchet mechanism.

The rotatable winding member onto which the flexible elongate member, e.g. tape, can be wound can be provided below the counter top. However, it is preferably provided above the counter top, to allow for easier and more convenient installation, such as close to the rotatable (screen) dispensing member. For example, the tzfindir:g member d~~pensig member are preferably provided above the window, such as so they cannot be seen from the gunman's side. If this arrangement is employed, then it is preferred that one or more pulley means are provided to allow travel of the or each flexible elongate member in a outwardly direction (e.g. from the dispensing member), around the pulley means and in an return direction (e.q. to the rotatable winding member).Each pulley means may comprise a pulley or wheel (or other suitable rotatable devices), preferably for a respective flexible elongate member.

Preferably if pulley means are provided it is located above the counter top (usually on the cashier's side) then they can be suitably located at sides of the window, such as in line with the side edges of the screen. Each pulley means may thus be situated inside a respective guide (e.g. slot or channel) to thereby conceal each pulley means.

Where a rail is provided (on the leading edge of the screen) it will be preferred that recesses are provided in portions of the rail that correspond to the or each pulley means. This may be so that the rail does not contact any pulley means, and so the leading edge of the rail (or deformable strip) will contact the counter top and will not be prevented from doing so merely by provision of only pulley means.

One or both of the locking mechanism or release mechanism may have the following features. Apart from both mechanisms preferably comprising a ratchet arrangement, the pawls of the two mechanisms are preferably biased towards each other by a spring. Suitably both pawls pivot around a common pivot for a pawl control member (such as a bar). The pawl control member is suitably capable of allowing one pawl to engage with the sprocket wheel while preventing the other pawl from engaging with the sprocket wheel. The two pawls need not act on the same sprocket wheel while preventing the other pawl from engaging with the sprocket wheel. The two pawls need not act on the same sprocket wheel, although for convenience this is preferred.The sprocket wheel can be connected to either side of the rotatable winding member or rotatable dispensing member.

Movement of the pawl control member (such as rocking motion), which may be effected by the ratchet disengagement means, may thus move one pawl into engagement with the sprocket wheel while moving the other pawl out of engagement with the sprocket wheel. In this manner the pawl control member can control the direction of rotation of the sprocket wheel (and thus also of one or more of the rotatable members), depending on the position of the pawl control member. The pawl control member may thus have means for moving each pawl towards, and away from, the sprocket wheel. For example, two such means may be provided, one for each pawl.

Preferably a housing will be provided which will conceal any or all of the rotatable winding member, rotatable dispensing member, locking mechanism, screen and/or release mechanism. Preferably all of these elements will thus not be visible from the gunman's side of the window, and indeed will not usually be visible by the cashier.

The ratchet disengagement means (such as a lever or pushrod) may extend outwardly from the housing. The housing may be provided with an elongate slot or opening which may allow the passage of the flexible screen (and preferably also the leading rail) therethrough.

second aspect of the present invention relates to a screen operating mechanism comprising a flexible screen that can be dispensed from a rotatable dispensing member, the dispensing member biased to wind the screen onto the dispensing member, the screen being connected to a rotatable winding member by one or more flexible elongate members, the winding member biased to wind each elongate flexible member onto the winding member, and a dispensing member and/or winding member release mechanism, the biasing force of the winding member being greater than that of the dispensing member so that on activation of the release mechanism the or each flexible elongate member is wound onto the winding member so dispensing the flexible screen from the dispensing member.

A third aspect of the present invention relates to a ratchet mechanism comprising a toothed sprocket wheel, a first pawl and second pawl, each pawl capable of being engaged and disengaged from the sprocket wheel, the first pawl allowing rotation of the sprocket wheel in a first direction and the second pawl allowing rotation of sprocket wheel in a second direction opposite from the first direction, whereby disengagement or engagement of the first pawl with respect to the sprocket wheel causes, respectively, engagement or disengagement of the second pawl with respect to the sprocket wheel.

According to a fourth aspect of the present invention there is provided a method of screening a window, the method comprising providing a screening device which comprises a counter above which is located a window and a flexible screen which can se moved across the screen to obscure at least part of the field of view through the window, and triggering the movement of the screen by provision of an alarm signal.

A fifth aspect of the present invention relates to a method of installing a screening device, the method comprising placing a screening devise on, above below or to one side of a window which is located above a counter, where the screening device is provided with a flexible screen which can be moved across the window to obscure at least part of the field of view through the window, and constructing the screening device so that the movement of the screen is capable of being triggered on provision of an alarm signal.

Preferred features and characteristics of the second, third, fourth and fifth aspects are as for the first mutatis mutandis.

The invention will now be described by way of example with reference to the accompanying drawings which are provided for reasons of illustration and are not to be construed as being limiting on the invention: Figure 1 is a longitudinal section through a first embodiment of a screening device according to the present invention; Figure 2 is a front elevation of the screening device in Figure 1; Figure 3 is a side elevation view of a release mechanism that can be provided with the screening device of Figures 1 and 2, the release mechanism being in an active (or latched) condition; Figure 4 is a side elevation view of the release mechanism of Figure 3 in an unlatched condition; Figure 5 is a longitudinal section through a second embodiment of a screening device according to the present invention;; Figure 6 is a section of a roller, screen and rail of the screening device of Figure 5; Figure 7 is a front elevation of a release mechanism; and Figure 8 is a front elevation of the screening device of Figure 5 incorporating the release mechanism of Figure 7.

Referring firstly to Fiaure 1 there is provided a screening device 1 comprising a counter 3 above which is located a window 5. The window comprises a number of laminated layers of glass and plastics material (such as polycarbonate) so as to make the window resistant to ballistic attack by firearms or other forms of force.

The device 1 has a flexible screen 7 which is dispensed from a rotatable dispensing member which is a roller 9.

The screen 7 and roller 9 are provided by a roller blind.

A leading edge of the screen 7 is provided with a rail 11 which prevents fraying and distortion of the material making up the screen 7. The leading edge of the rail 11 (which is downward facing) is provided with a deformable strip 13 which has the same length as that of the rail 11. The deformable strip 13 15 made of a cushioning material such as soft padding, such as foam, so that injury or damage to an object or a part of the body (such as a hand or arm) can be mitigated, or prevented, if the object or part of the body is struck by the deformable strip 13 by virtue of its downward movement.

The roller 9 is biased to wind the screen 7 onto the roller 9. This is achieved by providing biasing mechanism which is a helical torsion spring mounted internally inside the first roller 9. Attached to respective ends of the rail 11 are two flexible elongate members in the form of tapes 15 which are wound onto a rotatable winding member which is a roller 17 via respective pulleys 19. The tapes 15 thus pass in a vertically downward direction close to, and parallel with, the windows before being passed around a respective pulley 19 to then travel upwards (again close to, and parallel with the window 5) before being wound onto the roller 17 to which they are attached. Like the roller 9, the roller 17 is provided with an internal helical torsion spring. The roller 17 is biased so that both the tapes 15 are wound onto the roller 17.The force of the helical torsion spring inside the roller 17 is stronger than that inside the roller 9 and therefore under equilibrium conditions the tapes 15 will be wound onto the roller 17 thereby pulling the rail 11, and thus also the screen 7, in a downward direction (parallel to the windows) so that the field of view through the window is obscured.

In use the roller 9 and roller 17 will both be enclosed by a housing (not shown). This housing will have an elongate slot through which the rail 11 and screen 7 can freely pass. Both of the two tapes 15 will usually be housed within concealing channels or slots so that the tapes 15 are not easily visible. Likewise, both of the pulleys 19 will be concealed in an appropriate enclosure, such as the channels or slots. Although in Figure 1 both the rail 11 and screen 7 are positioned next to the window (and therefore visible) the rail 11 will visually be above the window 5 in the active or latched condition and will usually be concealed inside the housing.

One end of the roller 17 is provided with an externally toothed sprocket wheel 21 (see Figures 2, 3 and 4). The wheel 21 is provided with a number of teeth 23 which are shown in more detail in Figures 3 and 4. The release mechanism which acts to release the screen 7 so that it is pulled downwardly over the window 5 is positioned to act on the sprocket wheel 21. The release mechanism is shown in greater detail in Figures 3 and 4.

Figure 3 shows the release mechanism 25 in the active or latched condition. The screening device 1 is in the active condition (and compact state) whereby provision of the alarm signal will trigger the downward movement of the screen 7. The release mechanism 25 is provided with a horizontal arm 27 which on its lower side is provided with a notch 29 which engages a first pin 31. The arm 27 moves about a first pivot 33 at one end. The opposite end of the arm 27, which is a free end, is thus movable and it is the upward movement of the free end 35 of the arm 27 that triggers the release mechanism 25. A solenoid 37 is provided above the free end 35 of the arm 27 via a connector 39. The alarm signal is an electrical signal and such a signal activates the solenoid 39 causing upward movement of the connector 39 and therefore also the free end 35 of the arm 27.This movement of the arm 27 disengages the first pin 31 from the notch 29.

A bar 41 is provided which has the first pin 31 at a lower end 53 and a second pin 43 at an upper end 55. The bar 41 is pivoted about a second pivot 45. The second pivot 45 is shared by a first (upper) pawl 47 and a second (lower) pawl 49. The two pawls 47 and 49 are biased towards each other, and towards the sprocket wheel 21, by a first spring 51.

When the arm 27 is moved upwardly to pivot around the first pivot 33 the first pin 31 is disengaged from the notch 29. The lower end of the bar 53 is then pulled towards the first pivot 33 by means of a second spring 57 which is connected between the lower end 53 of the bar 41 and the first pivot 33. As the bar 41 pivots about the second pivot 45 this results in the upper end of the bar 55 moving away from the sprocket wheel 21. The first pawl 47 is provided with a shoulder 59 which engages with the second pin 43 such that motion of the upper end of the bar 55(to the right in Figures 3 and 4) moves the second pin 43 likewise. The first pawl 47 is thus moved away from the sprocket wheel 21 so that the first pawl 47 and sprocket wheel 21 are disengaged. This will allow the sprocket wheel 21 to rotate clockwise. Since the second pawl 49 is biased towards the first pawl 47, and the first pin 31 has moved (with the lower end of the bar 53) away from a shoulder 67 on the second pawl 47 movement of the first pawl 47 away from the sprocket wheel 21 simultaneously results in the second pawl 49 engaging with the sprocket wheel 21. This engagement is such that anti-clockwise motion of the sprocket wheel 21 -s prevented.

Thus once the sprocket wheel 21 is allowed to rotate clockwise of its own motion the greater bias in the spring of the roller 17 over the bias of the spring inside the roller 9 causes the tapes 15 to be wound onto the roller 9. The tapes 15 pass underneath their respective pulleys 19 thus pulling the rail 11, and therefore also the screen 7, in a downward direction across the window 5. This downward motion of the rail 11 and screen 7 continues until the rail 11 hits a stop which will be either the counter top 4 or an angled strip 61. The angled strip 61 may serve to help deflect any object that is caught between the rail 11 on its descent and the angled strip 61.The rail 11 has two cut-away portions 59 at each end which are larger than the pulleys 19 so that the pulleys 19 do not prevent the deformable strip 13 contacting either the counter top 4 or angled strip 61.

The rail 11 and screen 7, once their motion has been terminated, cannot be moved in an upwardly direction since the sprocket wheel 21 cannot rotate anti-clockwise due to engagement of its teeth 23 with the second pawl 49. This provides a locking mechanism such that upward movement of the rail 11 and screen 7 is thus prevented.

When the counter screen device 1 is to be reset into an activated state, the rail 11 must firstly be retracted in an upwardly direction. A reset mechanism is provided in the form of a push-rod 63 which is fixed to the upper end of the bar 55. The push-rod protrudes through a housing 65 which conceals the roller 9, the roller 17, the rail 11 and screen 7 during the active condition, and the release mechanism 25. When the push-rod 63 is moved towards and into the housing the upper end of the bar 55 is moved towards the sprocket wheel 21 (see Figure 4).

Thus the first pin 31 will be moved away from the sprocket wheel 21 and will bear upon the shoulder 67 provided on the second pawl 49. This will result in the disengagement of the second pawl from the sprocket wheel 21. The push-rod 63 is moved to an extent whereby the first pin 31 will travel until it rests underneath the notch 29, and will engage the notch 29 by the action of gravity on the arm 27. With the simultaneous movement of the second pawl 49 away from the sprocket wheel 21, by virtue of the second spring 57, connecting the two pawls 47 and 49, the first pawl 47 will engage one of the teeth 23 on the sprocket wheel 21. This will then prevent clockwise motion of the roller 17 (and therefore downward movement of the screen 7). Once the first pin 31 has engaged the notch 29 the release mechanism 25 is again in the active condition, ready for triggering by the alarm signal.

Thus the engagement of either the first or second pawl 47 or 49 with the teeth 23 on the sprocket wheel 21 is such that rotation of the wheel 21 is prevented in the clockwise direction by pawl 47 and in an anti-clockwise direction by pawl 49. In either case rotation in the direction allowed by one of the pawls results in the other pawl being pushed away from the wheel 21 due to the angle of engagement between the pawl and the teeth 23.

The push-rod 63 may be moved by direct manual pressure or it may only be moved as a result of a key turning a locking device. In addition, the push-red 63 Tnay bo actuated remotely, for example it may be moved by the activation of a solenoid. An electrical signal may be provided by a key operated mechanism whereby only a specific key will allow an electrical impulse to be sent to the solenoid to move the lever 63.

Figures 5, 6, 7 and 8 show a screening device in accordance with a second embodiment of the present invention. Parts or components of the screening device that are common to the screening device of the first embodiment in Figures 1 to 4 have been accorded the same reference numerals.

Thus, there is provided a screen device 1 which comprises a counter 3 above which is located a window 5. A flexible screen 7 is dispensed from a rotatable dispensing member in the form of a roller 9. Screen 7 and roller 9 form part of a roller blind. The screen 7 is provided with a rail 11 which is provided, by its lower side, with a deformable strip 13.

Unlike the screening device of the first embodiment, the screen device shown in Figure 5 has only one roller 9.

This is biased against movement of the screen 7 and rail 11 downwardly. However, the weight of the rail 11 is sufficient such that on release by provision of the alarm signal the screen 7 will move rapidly downwards, pulled by the rail 11. Thus, the gravitational force of the rail 11 is greater than the force provided in the opposite direction by the roller 9, which is provided with an internal helical torsion spring. The roller 9 provides a retarding force which will slow down the rail as it travels downwards. However, the force that roller 9 exerts will not be sufficient to prevent the rail 11 coming close to, or contacting, the counter top 4.

However, the roller 9 ill assist in retraction (upward movement) of the screen 7 and rail 11 and the weight of the combined rail 11 and screen 7 may be such that, after deployment of the screen 7, the gravitational force acting on the screen 7 and rail 11 balances, or is slightly less than, the force provided by the roller 9.

Thus, the roller 9 may, in some circumstances, provide a force that is just sufficient to cause slow upward movement of the screen 7 and rail 11 after deployment.

Thus, the roller 9 acts as a second biasing mechanism while the rail 11 can act as a first biasing mechanism.

On the rear side of the rail 11 (facing the cashier) there is provided a manually operable release mechanism 69 which is in the form of an espagnolet lock. This lock is key operated although the key mechanism can be replaced by a manually movable device so that the lock can be operated quickly and easily without recourse to a key.

Inside the mechanism 69 is a bar having two pivotable linkages, one at each end of the bar (not shown). These linkages are linked to a respective rod 71. Rotation of a key in the mechanism 69 (or movement of the manually operable device) results in rotation of the bar (not shown) which, via the two linkages, results in sideways movement of the rods 71 within the rail 11.

Figure 7 shows the release mechanism which comprises a pair of latches 73, each provided with a pivot 75, 77.

The latches 73 have, at each end, a linkage joined to a bar 79, 81, both of which are movable by a solenoid 83 situated therebetween. When an alarm signal is provided, in the form of an electrical signal, this actuates the solenoid 83 and roves both of the bars 79 and 81 in towards the solenoid. The latches 73 thus pivot around the pivot 75 and 77 so that they move outwards and disengage with the ends of the rods 71. The electrically operated release mechanism shown in Figure 7, and manually operable release mechanism shown in Figure 8, are both part of the same screening device but are separated for the sake of clarity.

The manually operable release mechanism is operated by turning a key in the mechanism 69. This causes both of the rods 71 to move towards the espagnolet lock 69 and into the rail 11, thus disengaging themselves from the latches 73. The ends of the rods 71 therefore act as retractable protrusions. Actuation of either solenoid 83 by an electrical signal, or operation of the manual release mechanism 69 will cause the screen to move rapidly downwardly as a result of the influence of gravity on the rail 11.

To prevent unwanted retraction of the screen, a locking mechanism is provided, and is shown in Figure 8. This mechanism, or catch means, prevents upward movement of the screen 7 after deployment. Two fixed detents 85 and 87 are provided which have slanting surfaces along which the retractable protrusions, provided by the ends of the rods 71, and slide. As the rail 11 passes downwardly towards the counter top 4, the rods 71 are both forced inside the rail 11 as their ends slide along the detents 85 and 87. Once past these detents, the rods 71 spring upwardly and become fixed underneath the detents 85 and 87, thereby securing and holding the screen (and rail 11). Thus, the rods 71 are preferably biased outwardly (to protrude from the rail 11). The detents 85 and 87 are suitably provided above the counter d or within appropriate concealing slots or channels.

Claims

(?T.h TMS

1. A screening device (1) comprising a counter (4) above which is located a window (5), and a screen (7) which can be moved across the window to obscure at least a part of the field of view through the window, the movement of the screen (7) capable of being triggered by provision of an alarm signal.

2. A screening device as claimed in claim 1 wherein the screen moves in a sliding motion.

3. A screening device as claimed in claim 1 or 2 having channels or slots which serve to guide the motion of the screen.

4. A screening device as claimed in any preceding claim wherein the screen moves downwardly across the window (5).

5. A screening device as claimed in any preceding claim wherein the direction of motion of the screen is in the plane of the window.

6. A screening device as claimed in any preceding claim wherein the alarm signal is provided by an alarm system which is manually triggered.

7. A screening device as claimed in any preceding claim wherein the alarm signal is electrical.

8. A screening device as claimed in any preceding claim wherein the screen is made of a textile material, fabric material, plastics material or is metallic.

9. A screening device as claimed in any preceding claim which is provided with, on one or both sides, a warning, instruction, or information.

10. A screening device as claimed in any preceding claim wherein the flexible screen is dispensed from a rotatable dispensing member (9).

il. A screening device as claimed in any preceding claim wherein a release mechanism (25,73), is provided to prevent movement of the screen across the window.

12. A screening device as claimed in claim 11 wherein the release mechanism is activated by an alarm signal.

13. A screening device as claimed in claim 11 or 12 wherein the release mechanism is a latch (73).

14. A screening device as claimed in any of claims 10 to 13 wherein a biasing mechanism acts to wind the flexible screen onto the dispensing member (9).

15. A screening device as claimed in claim 14 wherein the biasing mechanism is a torsion spring.

16. A screening device as claimed in claim 14 or 15 wherein the biasing mechanism is a torsion spring mounted internally inside the rotatable winding member.

17. A screening device as claimed in any preceding claim which is provided with a second biasing mechanism.

18. A screening device as claimed in claim 17 wherein the second biasing mechanism is a weight mounted on a rail (11).

19. A screening device as claimed in claim 17 wherein the bias of the first biasing mechanism is stronger than that of the second biasing mechanism.

20. A screening device as claimed in any preceding claim which is provided with a locking mechanism (85,87) which prevents retraction of the flexible screen.

21. A method of screening a window (5), the method comprising providing a screening device (1) which comprises a counter (4) above which is located a window (5) and a flexible screen (7) which can be moved across the screen to obscure at least part of the field of view through the window, and triggering the movement of the screen by provision of an alarm signal.

22. A method as claimed in claim 21 wherein the screening device is as claimed in any of claims 1 to 20.

23. A method of installing a screening device, the method comprising placing a screening device (1) on, above, below or to one side of a window (5) which is located above a counter (4), where the screening device is provided with a flexible screen (7) which can be moved across the window (5) to obscure at least part of the field of view through the window, and constructing the screening device so that the movement of the screen is capable of being triggered on provision of an alarm signal.

24. A method as claimed in claim 23 wherein the screening device is as claimed in any of claims 1 to 20.

25. A screening device, screen operating mechanism or ratchet mechanism substantially as herein described with reference to the accompanying drawings.