GB2145454A

GB2145454A - Roller shutter door

Info

Publication number: GB2145454A
Application number: GB08322637A
Authority: GB
Inventors: Gordon Mcilwrick
Original assignee: SHUTTER DOORS Ltd
Current assignee: SHUTTER DOORS Ltd
Priority date: 1983-08-23
Filing date: 1983-08-23
Publication date: 1985-03-27
Also published as: GB2145454B; GB8322637D0

Abstract

A roller shutter door which allows for expansion of the lath curtain (20) due to heat in the eventuality of a fire has each lath formed of two lath members (22,25) which interengage in overlapping relationship by means of the formations (29,30) on their longitudinal edges. This allows relative longitudinal movement between interengaging lath members (22,25) and also increases the strength and bowing resistance of the curtain (20). Insulating cavities between the lath members may be provided. <IMAGE>

Description

SPECIFICATION Roller shutter door This invention relates to roller shutter doors and in particular to roller shutter door curtains which are used for fire protection purposes.

Such roller shutter door curtains comprise rolled steel laths extending along the length of the curtain in side-by-side disposition and which interconnect along their longitudinal edges. Each of such laths is provided at each end with an endlock which locates in an upstanding door guide. The door guides and the longitudinal interlocking of the laths prevent disengagement when bowing occurs in the event of a fire, thereby maintaining the integrity of the door as a fire screen. The maintenance of the integrity of the curtain across the length of the doorway depends upon the size and shape of the quirks or interconnecting rolled formations along the longitudinal edges of the laths, which are required to maintain mutual engagement and avoid opening up under the heat to which the door may be subjected in use in the event of a fire.Such opening tendency is further aggravated by bowing of the door curtain caused by an expansion thereof greater than that which can be accommodated within the depth of the door guides. With larger doors, for example of 7500mm in length and longer, the abovementioned problems are increasingly acute.

It is an object of the present invention to provide a roller shutter door which avoids or mitigates to a substantial extent the abovementioned problems and disadvantages.

The invention provides a roller shutter door comprising a curtain formed of a plurality of laths extending longitudinally of said curtain, each lath having formations along its longitudinal edges adapted to engage corresponding formations on an adjacent lath, and a plurality of endlocks located at each end of said curtain by means of which ends of said laths may be supported in a guide channel, each endlock being connected to an endlock disposed at the opposed end of said curtain by means of at least two mutually interengaging laths.

The mutually interengaging laths connecting an endlock with an endlock disposed at the opposed end of said curtain may be in face-to-face overlapping disposition. Alternatively they may be in longitudinal edge-toedge overlapping disposition.

The invention will now be further described with reference to the accompanying drawings, in which: Figure 1 is a perspective scrap view in end section of a roller shutter door curtain of previously known type, Figure 2 is a view similar to Fig. 1 of a roller shutter door curtain in accordance with one embodiment of the invention, Figure 3 is a front elevation of the door of Fig. 2, Figure 4 is a front elevation of a second embodiment, and Figure 5 is a view similar to Fig. 2 of an alternative lath arrangement.

Referring now to Fig. 1 there is shown a part of a roller shutter door curtain 10. Two laths 11, 12 are shown, the curtain 10 being made of a large number of such laths extending longitudinally of the curtain 10 and each lath being in longitudinal edge-to-edge contact with the adajcent laths in the manner hereinafter described. Each lath 11, 12 has upper and lower rolled edge formations or quirks 13, 14 respectively, the upper edge formation 13 of one lath 11 interengaging with the lower edge formation 14 of the adjacent lath 12. Such edge formations 13, 14 maintain the laths 11, 12 in mutual edge-to-edge engagement whilst allowing relative pivotal movement therebetween as the door curtain 10 is raised and lowered.

Referring now to Figs. 2 and 3 there is shown a roller shutter door curtain 20 having inner laths 21, 22 mutually interengaging by means of edge formations 23, 24 corresponding with laths 11, 12 and edge formations 13, 14 of the previously described arrangement. The end of laths 21, 22 are provided at their ends with endlocks 27 which locate in upstanding door guides 28. In this case however the inner laths 21, 22 are in two parts which are separated by a respective expansion gap 29. The structural integrity of each inner lath 21, 22 is maintained by means of respective outer lath 30, 25, only outer lath 25 being shown in Fig. 2 for clarity. The outer laths 30, 25 are each provided with longitudinal edge formations 26, 27 which engage formations 23, 24 of inner laths 21, 22 as well as the edge formations 26, 27 on an adjacent outer lath 30, 25.Each outer lath 30, 25 extends across a respective expansion gap 29 and is received in the two parts of an inner lath 21, 22 to a relatively long depth.

The edge formations 23, 24, 26, 27 allow relative movement between inner and outer laths 21. 22, 30,-25 due to expansion in the event of a fire, thereby allowing relative movement between the two parts of each inner lath 21, 22.

For greater strength and structural rigidity the expansion gaps 29 are staggered between adjacent laths, as shown in Fig. 3.

Referring now to Fig. 4 there is shown a roller shutter door curtain 40 comprising a plurality of inner laths 41 and outer laths 42.

The inner and outer laths 41, 42 interengage by virtue of their longitudinal edge formations as described in relation to the previous embodiment. In this case however each lath 41, 42 has an endlock 43 provided at one end which locates in a respective upstanding door guide 44, whilst the other end of each lath 41, 42 is free. As shown the consecutive endlocks 43 located in each door guide 44 are provided alternately on inner laths 41 and outer laths 42. For structural reasons such an arrangement is preferred, although all of the endlocks 43 provided on the inner laths 41 could be located in one door guide 44 and all of the endlocks 43 provided on the outer laths 42 could be located in the other door guide 44 is desired. In either case relative movement between associated inner and outer laths 41, 42 accommodates expansion of the laths due to heat in the event of a fire.

Referring now to Fig. 5 there is shown an alternative arrangement of inner and outer laths 51, 52 of a roller shutter door curtain 50. The arrangement shown provides an insulating cavity 53 between the inner and outer laths 51, 52 to reduce the heat transfer across the curtain 50 in the event of a fire to one side thereof. This arrangement may be incorporated in the embodiments of door curtain illustrated in Figs. 3 or 4. With such an arrangement of laths 51, 52 providing a cavity 53 the ends of each cavity may be covered by a cover plate (not shown) fastened to the laths by nuts and bolts on which fusible washers, of for example aluminium, or p.v.c, are retained and which will melt in the event of a fire to allow relative movement of the laths due to expansion. Similarly any fittings secured to the door curtains 20, 40 or 50 may be secured thereto using fusible washers.

If desired the cavities 53 may be filled with a heat insulating and/or fire resistant material to give added protection.

The roller shutter doors of the present invention are particularly suitable when doors of at least 750mm length are required since the expansion of such doors in the event of a fire cannot readily be accommodated within the depth of the door guides. The double lath type of construction improves the strength of the curtain in comparison with known curtain constructions. in consequence bowing of the present curtain is eliminated or at least reduced to a substantial extent, thereby reducing the stresses on the quirks and ensuring prolonged engagement of the laths and integrity of the curtain under fire conditions.

Claims

1. A roller shutter door comprising a curtain formed of a plurality of laths extending longitudinally of said curtain, each lath having formations along its longitudinal edges adapted to engage corresponding formations on an adjacent lath, and a plurality of endlocks located at each end of said curtain by means of which ends of said laths may be supported in a guide channel, each of said endlocks being connected to an endlock disposed at the opposed end of said curtain therefrom by means of at least two interengaging lath members of a lath.

2. A roller shutter door according to claim 1, wherein said mutually interengaging lath members are in face to face overlapping disposition.

3. A roller shutter door according to claim 2, wherein one of said interengaging lath members overlaps two parts of the other of said interengaging lath members, one of said parts being connected to an endlock disposed at one end of said curtain and the other of said parts being connected to an endlock disposed at the opposed end of said curtain therefrom.

4. A roller shutter door according to claim 3, wherein said two parts of said other lath member are separated by an expansion gap.

5. A roller shutter door according to claim 4, wherein the expansion gaps of adjacent laths are displaced from each other longitudinally of said curtain.

6. A roller shutter door according to claim 2, wherein one of said interengaging lath members is connected to an endlock disposed at one end of said curtain and the other of said interengaging lath members is connected to an endlock disposed at the opposed end of said curtain therefrom.

7. A roller shutter door according to claim 6 wherein each lath comprises inner and outer interengaging lath members, the outer lath members of adjacent laths being connected to respective endlocks disposed at opposed ends of said curtain.

8. A roller shutter door according to any one of claims 2 to 7 wherein the lath members of a lath interengage by means of the mutual interengagement of the longitudinal edge formations thereon.

9. A roller shutter door according to claim 8 wherein the overlapping of interengaging lath members provides an insulating cavity therebetween.

10. A roller shutter door according to claim 8 wherein the longitudinally opposed ends of each insulating cavity are covered by a cover plate fastened to the respective lath members by means of bolts on which fusible washers are retained.

11. A roller shutter door according to claim 9 or claim 10 wherein said insulating cavities are filled with a heat insulating and fire resisting material.

12. A roller shutter door according to any one of claims 1 to 11 having a length of at least 7500mm.

13. A roller shutter door substantially as hereinbefore described with reference to and as illustrated in Figs. 3 and 2 or 5 or Figs. 4 and 2 or 5 of the accompanying drawings.