GB1597396A - Closure for an opening in a vertical surface - Google Patents

Description

(54) A CLOSURE FOR AN OPENING IN A VERTICAL SURFACE (71) We, UTEC AB, a Swedish Body Corporate, of Fack, S-931 01 Skelleftea, Sweden, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention concerns a closure in a vertical surface.

The invention provides a closure for an opening in a vertical surface, the closure comprising a leaf or sheet of flexible material to be suspended over the opening by affixing its upper edge and being opened or closed by raising or lowering its lower edge, the raising and lowering being effected by means of at least two ropes, strings or the like, which are connected to a hoist means, each rope extending within a respective separate channel sectioned guide bar extending along a respective vertical side of the opening and each rope being connected to the lower portion of the leaf via a protection means for preventing uncontrol led lowering, which protection means, in response to a predetermined decrease in the load on the respective rope, is released to lock the lower portion of the leaf to the respective guide bar, said protection means comprising a spring urged rod movable relative to the leaf and connected to the respective rope, which rod is connected by links to a locking mechanism having ratchets pivoted in crosswise arrangement on a common shaft, the arrangement being such that under the action of the spring the rod drives the links so as to cause outward movement of both ends of each ratchet into engagement with the lateral flanges of the associated guide bar at any position of the lower portion of the leaf relative to the guide bars to thereby locked the leaf against movement relative to the guide bars unless the tension in the rope is of sufficient magnitude to override the action of the spring.

The ropes may each extend over a respective guide wheel adjacent the upper portion of the opening to pass onto a common drum included in the hoist means for raising and lowering the closure.

Switch means may be provided adjacent each rope, which switch means, on being contacted by a slackened rope, interrupts the current to the drive unit of the hoist means.

An emnbodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which: Figure 1 is a front view of a closure provided with a lowering protection device and shown in the closed position, Figure 2 is a vertical section through the closure shown in Figure 1 and shows in a schematic way by das-dotted lines also the open position of the closure, Figure 3 is a section along the line III III in Figure 1, and Figures 4 and 5 are a lateral view and a section along the line V-V in Figure 4 respectively of the lowering protection device.

Referring to the drawings, 1 designates generally a leaf of a closure for an opening, one or both sides of which consist of cloth or other flexible material. The closure also includes several rigid cross-members 3 in mutually spaced relationship. The crossmembers are connected to the cloth by means of external strips 2 and are guided at their ends in substantially U-shaped or channel sectioned guide bars 4 attached to the vertical defining surfaces of the opening. The upper portion of the leaf 1 is susnended from a box 5 attached to the upper horizontal defining surface of the opening, which box includes a hoist means 6 with ropes, strings 7, 8 or the like, which are connected to the lower cross-member 3a of the leaf and by means of which and of the hoist means 6 the leaf can be hoisted to the position indicated in Figure 2 bv dashdotted lines, and be lowered to the position indicated in Figures 1 and 2 bv fullv drawn lines for revealing and obscuring the opening resPectively.

The two robes 7 and R are attached each to one end of the lower cross-member 3a of the leaf and from there extend along in the respective guide bar 4 in upward direction, each to a respective guide wheel 9 in the box 5. They then continue to a drum 10, which is common for both ropes is included in the hoist means for raising and lowering the leaf.

The hoist means 6 in the embodiment shown comprises, in addition to said drum, an electrically operated self-locking toothed gear 11, which is controlled from a coupling and control box 12 comprising control means for "UP" and "DOWN" movement.

The ropes 7 and 8, thus, are located and protected within the guide bars 4. In order to prevent the leaf 1 from damaging the ropes by engagement therewith by the ends of its cross-members upon movement, at least some of the cross-members 3, and preferably all of them, are provided at their ends with end stop members 13, which in co-operation with stop members 14 provided in the guide bars 4 limit the movement of the cross-members of the leaf in lateral direction to such an extent that said end stop members 13 never can come closer to the wall 15 of the guide bars facing the vertical defining surfaces of the opening than a dis tance which is greater than the rope thickness. In the embodiment shown, the stop members 14 consist of the rear surfaces of holding bars 16 for sealing strips 17 provided on each side of the leaf 1. The strips extend over the entire height of the opening.

For opening the leaf, the gear 11 is moved in such a direction, that the ropes 7 and 8 are wound on the drum 10 and thereby lift the lowermost cross-member 3a of the leaf. During the continued lifting movement, thus, the cross-members 3 are stacked one upon the other and the cloth is is folded together symmetrically. The upper positon of the leaf is determined by upper limit position stop units 18 located on each side of the opening. Said units comprise a so-called interlocked limit switch, which which when being actuated by the upper surface of the upper cross-member or by another means connected therewith interrupts the current from the "UP"-control to the gear, which thereby is stopped and can be started again only by means of the "DOWN"-control. Said units further comprise a main limit switch, which is switched on- and interrupts the main current to the gear drive motor only in the case when the interlocked limit switch does not operate.

There are, in other words, double safety devices. Each limit position stop unit 18, further, is provided with a slackrope switch 19, which abuts the rope and interrupts the current to the gear drive motor when the load on the rope drops and the rope is slackened.

Owing to the self-locking property of the gear 11, the leaf 1 can be stopped in any position. If during the lifting or lowerng movement, the leaf for some reason should start uncontrolled lowering, a lowering protection device automatically is released which safely locks the leaf against movement relative to the guide bars 4 and holds the leaf safely locked to the guide bars until it is subjected to an upward force of a predetermined magnitude.

Such a lowering protection device 20 is provided betwen the respective rope 7, 8 and the lower cross-member 3a of the leaf, and it comprises, as shown in Figures 4 and 5, a rope holder 21 for the rope which holder, by means of nuts 22, is attached adjustably on a vertical rod 23, and a locking mechanism generally designated by 24, which comprises a plurality of ratchets 25 and 26 arranged crosswise and having more or less pointed ends. Said ratchets are supported pivotally on a common shaft 28 located in a housing 27. In the embodiment shown, the locking mechanism comprises three such ratchets, the two ratchets designated by 25 are interconnected by a pin 29 and pivotally connected to the lower portion 31 of the vertical rod by a link 30 supported on said pin. The remaining ratchet 26 is located between the two ratchets 25 and ise pivotally connected to the lower portion of the vertical rod by a link 32, which by a pin 33 is connected to the ratchet 26. The vertical rod 23 is located movably in the housing 27 and provided witll stop discs 34, 35 located in spaced relationship one on each side of a partition wall 36 in the housing. Said discs limit movement of the rod relative to the housing. The housing 27 has a width slightly smaller than the distance between the inwardly directed lateral flanges 37 of the guide bar (see Figure 3) and is entirely open to said flanges, with which the ratches 25, 26 are intended to engage in order to stop and lock the leaf I against movement relative to the guide bar 4 as soon as the load on the rope drops below a predetermined value, which value is determined by a spring 38 clamped between the upper stop disc 35 of the vertical rod and the inside of the upper surface 39 of the housing.

At normal load on the ropes 7 and 8, which substantially is the dead weight of the leaf, the vertical rod 23 abuts with its lower stop disc 34 the partition wall 36 of the housing. At this position the ratchets 25, 26 are located entirely with the housing 27, and the leaf 1 can be lifted and lowered without being obstructed by the locking mechanism. However, when one of the ropes 7, 8 breaks, or when the load on a rope for- some reason drops below the force applied by the compressed spring 38 in the lowering protection device, the spring moves the rod 23 relative to the housing 27. Thereby the ratchets 25, 26 rapidly are pivoted out of the housing 27 into engagement with the lateral flanges 37 of the associated guide bar 4 and thereby lock the lower cross-member 3a of the leaf against movement relative to the guide bar.

At the same time as the load on the rope drops or ceases entirely, also the slackrop switch 19 is actuated, which thereby interrupts the current to the drive motor of the hoist means 6.

The lowering protection device acts in the locking position also as a lock, which renders lifting and lowering of the leaf 1 imposible, because both upwardly and downwardly directed forces on the lower cross-member 3a of the leaf cause the ratchets 25, 25 to additionally pivot outward and thereby bring about a still safer locking. This stopping and locking effect can be released only by an upwardly directed force acting upon the vertical rod 23 greater than the spring force, for example by stretching the rope by means of the hoist means 6. Even when the closure is in entirely closed position, i.e. when the lowermost cross-member 3q of the leaf with its lower surface, which may be provided with a clamp protection 40, entirely abuts the lower horizontal defining surface of The opening, the lowering protection devices will operate as an effective lock for the closure, which thereby cannot be opened unless the hoist means 6 can be started.

Each lowering protection device 20, thus, becomes operative and locks the leaf as soon as the rope load is less than the forces applied by the spring 38. By braking or lifting the lower cross-member of the leaf, for example manually, it is thus possible at any desired time to lock the leaf in any desired open position.

The present invention is not restricted to the embodiment described above and shown in the drawings,'but can be altered and modified in many different ways within the scope of the invention as set out in the attached claims. The device according to the invention, thus, also can be ap plied in connection with closures other than here described, if they can be opened and closed by vertical movement along at least a portion of the vertical defining surfaces of an opening.

WHAT WE CLAIM IS: 1. A closure for an opening in a vertical surface, the closure comprising a leaf or sheet of flexible material to be suspended over the opening by affixing its upper edge and being opened or closed by raising or lowering its lower edge, the raising and lowering being effected by means of at least two ropes, strings or the like, which are connected to a hoist means, each rope extending within a respective separate channel sectioned guide bar extending along a respective vertical side of the opening and each rope being connected to the lower portion of the leaf via a protection means for preventing uncontrolled lowering, which protection means, in response to a predetermined decrease in the load on the respective rope, is released to lock the lower portion of the leaf to the respective guide bar, said protection means comprising a spring urged rod movable relative to the leaf and connected to the respective rope, which rod is connected by links to a locking mechanism having ratchets pivoted in crosswise arrangement on a common shaft, the arrangement being such that under the action of the spring the rod drives the links so as to cause outward movement of both ends of each ratchet into engagement with the lateral flanges of the associated guide bar at any position of the lower portion of the leaf relative to the guide bars to thereby lock the leaf against movement relative to the guide bars unless the tension in the rope is of sufficient magnitude to override the action of the spring.

2. A closure according to claim 1, wherein the ropes each extend over a respective guide wheel adjacent the upper portion of the opening to pass onto a common drum included in the hoist means for raising and lowering the closure.

3. A closure according to any preceding claim, wherein switch means are provided adjacent each rope, which switch means, on being contacted by a slackened rope, interrupts the current to the drive unit cf the hoist means.

4. A closure substantially as herein described with reference to and as shown in the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   38 in the lowering protection device, the spring moves the rod 23 relative to the housing 27. Thereby the ratchets 25, 26 rapidly are pivoted out of the housing 27 into engagement with the lateral flanges 37 of the associated guide bar 4 and thereby lock the lower cross-member 3a of the leaf against movement relative to the guide bar.

   At the same time as the load on the rope drops or ceases entirely, also the slackrop switch 19 is actuated, which thereby interrupts the current to the drive motor of the hoist means 6.

   The lowering protection device acts in the locking position also as a lock, which renders lifting and lowering of the leaf 1 imposible, because both upwardly and downwardly directed forces on the lower cross-member 3a of the leaf cause the ratchets 25, 25 to additionally pivot outward and thereby bring about a still safer locking. This stopping and locking effect can be released only by an upwardly directed force acting upon the vertical rod 23 greater than the spring force, for example by stretching the rope by means of the hoist means 6. Even when the closure is in entirely closed position, i.e. when the lowermost cross-member 3q of the leaf with its lower surface, which may be provided with a clamp protection 40, entirely abuts the lower horizontal defining surface of The opening, the lowering protection devices will operate as an effective lock for the closure, which thereby cannot be opened unless the hoist means 6 can be started.

   Each lowering protection device 20, thus, becomes operative and locks the leaf as soon as the rope load is less than the forces applied by the spring 38. By braking or lifting the lower cross-member of the leaf, for example manually, it is thus possible at any desired time to lock the leaf in any desired open position.

   The present invention is not restricted to the embodiment described above and shown in the drawings,'but can be altered and modified in many different ways within the scope of the invention as set out in the attached claims. The device according to the invention, thus, also can be ap plied in connection with closures other than here described, if they can be opened and closed by vertical movement along at least a portion of the vertical defining surfaces of an opening.

   WHAT WE CLAIM IS: 1. A closure for an opening in a vertical surface, the closure comprising a leaf or sheet of flexible material to be suspended over the opening by affixing its upper edge and being opened or closed by raising or lowering its lower edge, the raising and lowering being effected by means of at least two ropes, strings or the like, which are connected to a hoist means, each rope extending within a respective separate channel sectioned guide bar extending along a respective vertical side of the opening and each rope being connected to the lower portion of the leaf via a protection means for preventing uncontrolled lowering, which protection means, in response to a predetermined decrease in the load on the respective rope, is released to lock the lower portion of the leaf to the respective guide bar, said protection means comprising a spring urged rod movable relative to the leaf and connected to the respective rope, which rod is connected by links to a locking mechanism having ratchets pivoted in crosswise arrangement on a common shaft, the arrangement being such that under the action of the spring the rod drives the links so as to cause outward movement of both ends of each ratchet into engagement with the lateral flanges of the associated guide bar at any position of the lower portion of the leaf relative to the guide bars to thereby lock the leaf against movement relative to the guide bars unless the tension in the rope is of sufficient magnitude to override the action of the spring.
2. 2. A closure according to claim 1, wherein the ropes each extend over a respective guide wheel adjacent the upper portion of the opening to pass onto a common drum included in the hoist means for raising and lowering the closure.
3. 3. A closure according to any preceding claim, wherein switch means are provided adjacent each rope, which switch means, on being contacted by a slackened rope, interrupts the current to the drive unit cf the hoist means.
4. 4. A closure substantially as herein described with reference to and as shown in the accompanying drawings.