This invention relates to surface mounted fire and smoke seals and, more especially but not exclusively, to such seals for sealing surfaces between a door and door frame.

Surface mounted seals are known which comprise an elongate backing strip of plastics material from one surface of which is upstanding a brush seal and to the other side of which is secured a layer of intumescent material. Such a seal is disclosed in our British Patent 2232702 and European Patent 040321 3.

One disadvantage of these seals when used to seal the adjoining surfaces of a door and door frame is a tendency for the backing strip to buckle in the presence of high temperatures thereby enabling smoke and or flame to pass between the door and its frame.

One object of the present invention is to provide a surface mounted seal which does not suffer from, or at least alleviates, this and other disadvantages.

According to the present invention in one aspect there is provided a surface mounted seal which comprises an elongate plastics mounting strip formed along one of its side edges with an upstanding wall from whose upper margin projects a strip of flexible plastics material, the flexible strip extending downwardly towards the mounting strip and subtending an angle to the wall of between 35 and 60° , a second flexible strip projecting

upwardly from the surface of the mounting strip and towards the first flexible strip to define with such strip the hypotenuse of a right-angled triangle whose other sides are defined by the upstanding wall and the length of mounting strip positioned between the second flexible strip and the wall, and a strip of intumescent material secured to the surface of the mounting strip between the side edge of the mounting strip remote from the wall and the second flexible strip.

The free edges of the two flexible strips may be spaced apart or be in contact one with the other.

Preferably, the flexible strips subtend angles approximating to 45° to the wall and the mounting strip respectively.

In another aspect, there is provided a surface mounted fire and smoke seal which comprises a plastics mounting strip which is turned through a right angle along one of its sides to define an upstanding wall, a first relatively flexible plastics strip extending downwardly from the upper margin of the wall and inclined towards the mounting strip at an angle approximating to 45° to the wall, a second relatively flexible plastics strip attached to the floor of the mounting strip and inclined upwardly therefrom at an angle approximating to 45° thereto, the two flexible strips lying in substantially the same plane with a spacing between their free edges

The invention will now be described by way of example only with reference to the accompanying diagrammatic drawings in which:-

Figure 1 is a plan view from above of a surface mounted seal in accordance with the invention; and

Figure 2 is an end view of the seal illustrated in Figure 1 ,

The illustrated surface mounted seal comprises a mounting strip 1

formed along one of its sides with an upstanding wall 2. The wall may be formed integrally with the strip 1 by bending the strip through a right angle or may be formed separate from the strip and subsequently secured to one edge of the strip. The strip and wall are of plastics material, preferably PVC. Secured to the upper margin of the wall 2 is a relatively flexible plastics strip 3. This strip 3 is inclined downwardly towards the floor of the mounting strip 1 and subtends an angle of between 35° and 60° to the wall 2. Preferably the angle approximates to 45 ° . Projecting upwardly from the floor of the mounting strip 1 is a second relatively flexible plastics strip 4. This strip 4 is inclined towards the strip 3 at an angle of between 35° and 60° (preferably 45 °) and defines with strip 3 the hypotenuse of a right angled triangle, the other two sides of which are defined by the wall 2 and that part of the floor of the mounting strip 1 between the wall 2 and the strip 4. A strip of intumescent 5 material is bonded to the floor of the mounting strip 1 from its side edge remote from the wall 2 to the edge of the second strip 4.

In use, the seal is secured by panel pins, adhesive or the like to the jamb of a door frame with the rear face of the wall 2 in contact with the door stop of the jamb. In one arrangement, double sided tape is attached to the underside of the floor of the mounting strip 1 , the tape covering being peeled off just before use. As the door closes into the jamb it makes contact with the strips 3 and 4, these deflecting inwardly to provide an effective seal between the door and the door jamb. Any buckling of the strip material which may occur in the presence of extreme heat will not affect the effectiveness of this seal.

It will be appreciated that the foregoing is merely exemplary of door trims in accordance with the invention and that modifications can readily be made thereto without departing from the true scope of the invention.