BI-PARTING SHUTTER SYSTEM

Abstract: A bi-parting shutter system 12 is provided for an enclosure (not shown) having an aperture therein which is covered by two slidably displaceable shutters 14, 16. The shutters 14, 16 are connected by a flexible belt 20 arranged in a track 18 and looped around two freely rotatable pulley wheels 22, 24. This arrangement defines a first belt run 26, which is connected to first shutter 14 by way of attachment means 30, and a second belt run 28 similarly connected to second shutter 16 by way of respective attachment means 32. In order to provide a compact arrangement the second arttachment means 32 includes a bracket member 34 having a generally hollow square cross section and located with the track 18. This permits the first belt run 26 to freely pass through the second attachment means. In this way movement of one shutter 14, 16 is transmitted to the other shutter without requiring a complicated or bulky connection.

Description: This invention relates to a bi-parting shutter system, particularly for cupboards or cabinets provided with two shutters which it is intended or desired to operate in co-operation with each other. The provision of one or more shutters to close an opening in a cupboard or cabinet is well known and such shutters are often a flexible roller-type shutter which is unfurled to cover the opening. Alternatively known shutters may be composed of a number of slats which are slideably housed within the cabinet or cupboard itself and move from an open position to a closed position when so required. Such shutters are often provided in pairs, each shutter covering one half of the access opening provided as part of the cupboard or cabinet. Similar arrangements are also known in relation to shutters, blinds, curtains etc. for windows or similar apertures. Where two such shutters are provided it is often desirable that movement of one shutter should cause simultaneous and corresponding movement of the other shutter. Thus, for example, when one shutter is moved from its fully open position to its fully closed position (covering half of the opening in the enclosure) the other shutter moves correspondingly from its fully open position to its fully closed position (covering the other half of the enclosure's opening) thus ensuring that the opening in the enclosure is completely covered. In order to provide such simultaneous and corresponding operation various forms of linkages have been proposed in the prior art. Such methods include the well known linking means consisting of a number of pulleys and wires connecting the two shutters such that displacement of a first shutter in one direction causes a corresponding displacement in a second shutter in the opposite direction. Our co-pending British pending application No. 8827127.5 provides a further method of linking two such shutters by way of a number of rigid pivotally mounted members operating in a cantilever-type configuration. These known methods however have several disadvantages. For example the known wire and pulley mechanisms require the provision of channels within the side walls of the enclosure for the wires to run through. If a wire should become detached or snagged within its channel it requires complete disassembly of the enclosure in order to free the wire and repair the apparatus. In the two embodiments proposed in our co-pending application the shutters are required to be of extra length, such as to include the top and bottom of the enclosure, in order to provide sufficient length to link the two ends of the shutters by the pivoted rigid members. In a second embodiment proposed in the co-pending application the shutters are linked at their respective moveable edges, however this causes the size of the access opening in the cupboard or cabinet to be restricted by the need to provide a track and slideable block assembly on each interior face of the cupboard or cabinet. GB-A-885999 discloses a shutter system in which two shutters are linked by a flexible belt arranged adjacent to at least one edge of each shutter. By attaching the two shutters to near and far belt runs, with respect to the cabinets front, the shutters are moved in opposing directions by a movement of only one shutter. This arrangement is, however, not sufficiently rigid to maintain a good relatively inflexible positioning of the two shutters. Furthermore, the mouldings required to provide unobstructed movement of the two shutters are complex easily displaced. It is an object of the present invention to provide a bi-parting shutter system which does not require the use of extra lengths of shutter, which has a small number of moving parts and does not restrict the size of the access opening provided in the enclosure. With this object in view, the present invention provides a bi-parting shutter system comprising two shutters slideably arranged within an enclosure so as to be displaceable from a closed position in which the shutters co-operate to cover an opening in the enclosure and an opened position in which the shutters are disposed within the enclosure and do not substantially cover the opening, the two shutters being connected to each other such that movement of one shutter causes a corresponding displacement in the second shutter, by a flexible belt passing through a track and having a closed looped configuration about guide means located at each end thereof thereby providing two mutually opposed belt runs, said track being disposed adjacent to one respective slideably displaceable edge of each flexible shutter, a first shutter being attached to a first run of the belt and a second shutter being attached to a second run of the belt characterised in that the guide means are arranged at each end of a track in which the flexible belt is located and the second shutter is attached to the second run by a bracket member having a hollow cross section and fitting closely and slideably within the track, with the bracket member being arranged so that the first run of the flexible belt passes therethrough. It will be appreciated that with the shutters attached in this manner movement of the first shutter, attached to the first belt run, will result in movement of the second shutter, attached to the second belt run, in the opposite direction and to an equal amount. Preferably two tracks are provided, each track with its own belt adjacent to one slideably displaceable edge of the two shutters. Such an arrangement ensures more positive tracking and guidance of each shutter during its movement. Advantageously the guide means are in the form of a rotatably mounted pulley or wheel about which the belt is guided. This arrangement ensures that the belt is positively tracked around the guide means and results in a smaller frictional force than would be present if the guide means were a fixed assembly. Preferably the second shutter is attached to the second run by a bracket member having a hollow, preferably substantially square, cross section, the bracket member being arranged so that the first run of the flexible belt passes therethrough. Advantageously the track is in the form of a C-shaped profile having a slit along one face thereof such that the first and second shutters may be attached to the first and second belt runs respectively. A bi-parting shutter system according to the invention may be arranged either vertically or horizontally such that the attached shutters are displaced respectively either up and down or from side to side. When the system is arranged horizontally it is advantageous to arrange the guide means at an angle with respect to the track's vertical axis such that the shutters, depending vertically therefrom, are at a mutually parallel disposition. In this way the shutters will be able to pass behind or respectively in front of each other as desired. This arrangement is especially advantageous for flexible shutters such as cutains or similar intended for covering or closing a window in a room or a building. Preferably a cord pull or motor drive are provided attached to the flexible belt so as to cause movement thereof in response to a control signal. The invention will be described further by way of example with reference to the accompanying drawing in which:- Fig. 1 is a sectional side view of a first preferred embodiment of the invention located in an enclosure, for example a cabinet; and Fig. 2 is a sectional view along the line II-II of Fig. 1. Referring firstly to Fig. 1, a preferred embodiment of a bi-parting shutter system according to the invention is attached to an enclosure 10 of which only one wall is shown for simplicity. The enclosure 10 may be a cabinet or similar structure or could be a room or building or any other form of box shaped enclosure. The enclosure 10 is provided with an opening in a front face thereof and one bi-parting shutter system 12 according to the invention is located immediately adjacent thereto. The opening in the enclosure is provided with two shutters 14, 16 which are slideably displaceable along a track (not shown) provided on the upper and lower surfaces of the enclosure 10. The shutters are thus displaceable between a closed position in which the shutters combine together to cover the opening 12 and an open position in which they are retracted therefrom, leaving the opening uncovered, and are housed within the enclosure 10. The bi-parting shutter system 12 comprises a track 18 of generally C-shaped profile (see Fig. 2) and arranged along substantially the whole length of one edge of the opening in the enclosure 10. The track 18 is provided with a flexible endless belt 20 arranged in a looped configuration about two freely rotatable pulley wheels 22, 24 located at respective ends of the track 18. Thus the flexible belt provides a first belt run 26 and a second belt run 28 parallel thereto between the two wheels 22, 24. Each belt run 26, 28 is provided with respective attachment means 30, 32 which are rigidly connected to their respective belt runs so as to be moveable therewith. The attachment means 30, 32 include respective pins projecting through a slit 33 in the track 18. First attachment means 30 is attached via its pin to one edge of the first shutter 14 and the second attachement means 32 is attached to one edge of the second shutter 16. Thus the movement of the two shutters 14, 16 is connected via the attachment means 30, 32 and the flexible belt 20. As will be seen more clearly in Fig. 2 the second attachment means 32 also includes a bracket member 34 having a generally hollow square profile and adapted for location with the C-shaped track 18. The bracket member 34 is directly attached to the second belt run 28 and the hollow profile permits the first belt run 26 to pass therethrough without any direct connection to the second attachment means 32. In order to provide more certain and controllable tracking and movement of the two shutters 14, 16 a second bi-parting shutter system 12 according to an aspect of the invention may be provided on mutually opposed faces of the enclosure 10 adjacent to the opening therein. Thus each shutter 14, 16 is attached to its counterpart at each moveable edge. It will be understood from the foregoing description that movement of, for example, the first shutter 14 in an upwards direction from the closed position will result in movement of the flexible belt 20 about the pulley wheels 22, 24. As the first attachment means 30 is moved along the first belt run 26 towards the upper wheel 22 the second belt run 28 and the connected attachment means 32 are also displaced by a corresponding distance towards the lower pulley wheel 24. Thus the second shutter 16 is moved downwards in conjunction with the raising of the first shutter 14. It will be appreciated that no braking mechanism is required with a bi-parting shutter system according to an aspect of the invention as a force produced by the tendency of the second shutter to move downwards is resisted by an equal force required to move the first shutter upwards and by frictional losses about the pulley wheels 22, 24. Thus there will be no slippage of the shutters during use. Furthermore movement of the first shutter 14 will always cause an equal amount of movement of the second shutter 16 and the shutters will always meet at the same predetermined point over the opening in the enclosure 10. The predetermined point is preferably the middle of the enclosure as otherwise one shutter would never be completly retracted from the opening. In an alternative embodiment a bi-parting shutter system is arranged substantially horizontal such that the shutters depend vertically from the linkage means and are slidably displaceable in a side to side manner. In this configuration the system includes one track which is preferably disposed above the shutters such that is operation is not inhibited. Where the shutters are inherently flexible, such as curtains or other similar articles, it is advantageous for the shutters to have an amount of overlap. One way in which such an overlap may be provided, without fouling of the shutters or the linkage means, is to incline the guide means at each end of the track at an angle thereto. In this way the shutters depending from the first and second belt runs will be displaceable along parallel paths and can overlap each other, when desired or required, without fouling. A further advantageous modification of all aspects of the invention is to provide a draw cord or chain etc attached by a pulley to the linkage means such that movement of the shutters may be borught about simultansously at a remote location. Alternatively a motor, or similar means, may be provided connected to the linkage means such that actuation of the motor will displace the shutters attached thereto. It will be understood that the foregoing is illustrative and not restrictive of the scope of the invention and variations may be made thereto. For example the flexible belt may be made of any desired material providing the operating characteristics of the shutter system are maintained. The rotatable pulley wheels 22, 24 may be replaced by rotating shafts or fixed shafts having a low frictional component, for example shafts made of PTFE. Alternatively the guide means could be provided by suitable moulding of the end of the track 18. In the drawings the track 18 is provided with a lip 36 which covers the attachment means 30, 32. This lip is not necessary and merely serves as a protection to prevent the ingress of dirt etc into the interior of the C-shaped profile. The shutters 14, 16 may be of any convenient configuration, for example of a flexible material such as a roller blind or of a slatted construction as is common for this type of cabinet configuration.

Claims: A bi-parting shutter system comprising two shutters (14, 16) slideably arranged within an enclosure (10) so as to be displaceable from a closed position in which the shutters co-operate to cover an opening in the enclosure and an opened position in which the shutters and do not substantially cover the opening, the two shutters being connected to each other such that movement of one shutter causes a corresponding displacement in the second shutter, by a flexible belt (20) passing through a track and having a closed looped configuration about guide means (22, 24) located at each end thereof thereby providing two mutually opposed belt runs (26,28), said track being disposed adjacent to one respective slideably displaceable edge of each flexible shutter, a first shutter (14) being attached to a first run (26) of the belt and a second shutter (16) being attached to a second run (28) of the belt characterised in that the guide means (22, 24) are arranged at each end of the track (18) in which the flexible belt is located and the second shutter (16) is attached to the second run (28) by a bracket member (34) having a hollow cross section and fitting closely and slideably within the track, with the bracket member being arranged so that the first run (26) of the flexible belt (20) passes therethrough. A shutter system as claimed in claim 1 wherein two tracks (12) are provided each track with its own belt adjacent to one slideably displaceable edge of the two shutters (14,16). A shutter system as claimed in claims 1 or 2 in which the guide means are in the form of a rotatably mounted pulley or wheel (22, 24) about which the belt (20) is guided. A shutter system as claimed in claims 1, 2 or 3 in which the bracket member (34) has a substantially square hollow cross-section. A shutter system as claimed in any preceding claim in which the track (12) is in the form of a C-shaped profile (18) having a slit (33) along one face thereof such that the first and second shutters (14, 16) may be attached to the first and second belt runs (26, 28) respectively. A shutter system as claimed in any preceding claim in which a cord is connected to the linkage means in order to cause displacement therefof and corresponding displacement of the shutters. A shutter system as claimed in any of claims 1 to 5 in which a motor is provided connected to the linkage means such that actuation will cause displacement of the shutters.

Inventors: JACKSON, JOHN
Applicants: ROTALAC PLASTICS LIMITED
Application year: 1990
Main classification: E05F17
IPC codes: E06B3, E05F17