GB2199652A - Sealing louvred dampers in ventilators - Google Patents

Description

1 1 j, 2199652 IMPROVEMENTS IN VENTILATORS- 1 1 The present invention

comprises improvements in ventilators and concerns controllable, louvred ventilators more particularly, although not exclusively, for roof mounting.

Such roof mounted ventilators provide for natural extract ventilation and for the exhaust of heat and smoke in the event of fire.

In order to facilitate the manufacture of louvred ventilators, and reduce costs, it is convenient to construct the louvres e.g. as aluminium extrusions, without louvre ends, and to seal the gaps between the louvre ends and the ventilator frame with pile weatherseal strips when the louvres are in their closed position. Such seals function first as draught seals and act cosmetically to avoid daylight entry through the aforementioned gaps when the ventilator is closed. The seals then als o act as water seals to.some extent, although usually water collection and drainage channels are. provided, inside the ventilator frame, to drain water penetrating past the seals and into the frame back out onto the outside of the roof for example. To further facilitate the collection and drainage of water off the outside of the louvres, particularly when the ventilator is mounted in a flat roof location, it is - 2 known to provide the louvres with leading and trailing edge formations which overlap one another in the closed position of the louvres and to collect water penetrating between the louvre overlapping portions in channels provided at the trailing -edges of the louvres, these channels opening at their ends below the pile weatherseal strips to drain water into internal water drainage channel members of the frame.

This arrangement requires that the outer faces of the louvres, when in their closed position, extend transversely at a shallow angle relative to the length wise direction of the pile weatherseal strips so as, for example, to be inclined downwardly towards the louvre leading edge channels with the pile weatherseal strips extending horizontally.

Problems arise in providing a sufficient width of pile weatherseal strip to accommodate the arrangement described in the immediately preceding paragraph. An overwide strip is not easily anchored in its usual T-slot because it tends to be dragged out by the transverse wiping action of the louvre blades as they open and close across the strip.

Furthermore, the strip has to be interrupted, or local apertures provided in it, in order to accommodate the louvre pivots. This is a troublesome operation. If two piled weatherseal strips are provided, 1 11, side by side to make up the required width of strip, the T-slots for mounting the strips dictate that a gap must be left between the strips. Such a gap forms a further leakagepath for water running off the outside of the louvres, into the ventilator.

According to the invention, at least two side-by-side, pile weatherseal. strips are provided having the top surfaces of their piles lying in a common plane and touching one another, the strips being of different transverse dimensions and having their T-slot mountings disposed in stepped relationship to one another.

A specific embodiment of the present invention will now be described in detail by way of example, and not by way of limitation, with reference to the accompanying drawings in which FIG. 1 is a cross-section of a left hand end portion of a controllable louvred roof ventilator of the present invention, with the louvres shown in full line in their.closed position and in phantom outline in their fully open position, the ventilator being mounted in a horizontal, flat roof position; FIG. 2 is an enlarged, left hand, top corner portion of a plan view of the ventilator; and 1 4 FIG. 3 is a section on line 3-3 in Fig. 2. With reference now to the accompanying drawings, the ventilator has a rectangular body comprising a base 10 presenting a base flange 11 for flashing the ventilator to the roof W. The base flange 11 is flat in the present example but it may be of any of the standard shapes suitable for flashing it to different kinds of sloping roof cladding or to glazing bars used in roof lights.

The base 10 has an upstanding wall 12 defining a rectangular ventilation opening 14 through the base. Ventilation through the opening 14 is controlled by the louvres 15 which also prevent weather entry through the opening when the louvres are closed.

The ventilator further comprises a readily removable outer body part 20 made up of opposite pairs of straight channel sectioned side members 16 and end members 18 removably interconnected with one another at their adjacent ends. The body part members 16, 18 are formed as extruded metal, e.g. aluminium, sections and each presents an equally spaced pair of walls extending away from the base flange 11 to the outside of the wall 12. The walls 16', 18' (see Figs. 1 and 3) of this pair of walls adjacent the wall 12 abut and interlock with the outside of the wall 12. Thus, the adjacent walls 16', 18', of all the members 16, 18 substantially correspond with one another in crosssectional size and shape to interfit with the wall 12 in the manner seen in Fig. 1. The webs or floors 16a, 18a of the channel members 16, 18 abut the base flange 11. The channel members 16,,18 act as internaldrainage channels for water which runs off the louvres 15 into the body part 20 of the ventilator. The other upstanding walls 1C, 1V of the channel members 16, 18 form a rectangular frame or box which shelters the ventilation opening when the louvres are open and which carries the pivots for the outer ends of the louvres 15. These louvre end pivots 22 are arranged as seen in Fig. 2-and are formed by headed pivot pins which are driven into the respective ends of part-cylindrical channels form ed in hollow partcylindrical (270') formations 2 extending along the longitudinal louvre centre lines, and corresponding formations 26 are also provided, extending parallel to the central formations 24, adjacent the inwardly opening, trailing edges of the louvres, for fixing-link-louvre pivots 56. The louvres 15 are cut to the required length from metal, e.g. aluminium, extrusions of the section indicated in Fig. 1 and are additionally provided with leading and trailing edge formations 28, 29 which overlap one another in the closed position of the louvres, as best shown in Fig. 1. The leading edge formations 28 carry elastomeric seals 30, which may be lip seals, carried by the formations 28 which seals then act to resist water penetrating under the leading edges of the louvres, and water penetrating under the leading edges of the louvres is trapped in the trailing edge rain channels 32 which also act to catch and drain off water into the channel members 16 of the body part 20.

The louvre end pivots 22 are provided with bearing shoulders 34 which bear directly in the walls 16" of the box and the pivot pins 22 are secured in the formations 24 by wing formations 22' on the pins which occupy cross-cuts 36 in the formations 24, formed prior to assembly of the ventilator, the pins being driven into the formations 24 until the wings 22' reach this position whereby the louvres 15 are predeterminedly positioned between the walls 16". To secure each louvre against rotation with respect to its pivot pins 22, the pins have splines 22" which fit closely between the free edges of the channel formation 24 of the louvre. The gaps between the louvre ends and the 1 t 9r 7 - walls 1C are sealed with pile weatherseal strips 38a, 38b mounted in open-ended T-slots 100, 101 formed on the insides of the walls 1C and form gaps 37 (see Fig. 1) at the ends of the channels 32 for the drainage of water from these channels, when the louvres are in a closed position, into the channel members 16. Thus, as may also be seen from Fig. 1, the louvres 15 extend, transversely, at a shallow angle relative to the lengthwise direction of the pile weatherseal strips 38a, 38b so as to be inclined downwardly towards the trailing edge rain channels 32 when the ventilator is mounted in a horizontal position.

As may be seen from Fig. 3, the pile weather seal strips 38a, 38b, extend side-by-side with the top surfaces of their piles lying in a common plane and touching one another, the upper strip 38a having larger transverse dimensions than the lower strip 38b and the T-slot mountings 100, 101 being disposed in stepped relationship to one another, the T-slot mounting 101 being positioned closer to the adjacent louvre ends of the louvres 15 than the T-slot mounting 100. Furthermore, referring to Fig. 2, the pile weatherseal Strip 38b is formed-in sections, each section extending between an adjacent 1 - 8 pair of the pivot pins 22 or between the pivot pin 22 and one end of a member 16 at the two ends of the ventilator respectively.

The sections of the strips 38b are readily cut to length and mounted in the T-slots 101 prior to inserting the louvre pivots. Due to the small transverse dimensions of the strips 38a, 38b, the strips are firmly anchored in their T-slots and resist removal by the wiping action of the louvre ends on the strips as the louvres are opened and closed. In particular, in the embodiment described with reference to the accompanying drawings, it will be noted that each strip 38a, 38b, is wiped sideways in one direction only by the louvre ends as the louvres are opened and closed. Each strip is, therefore, held firmly in its T-slot since there is no tendency to buckle the strip in its slot to drag the strip from beneth the undercut edges of the T-slot.

Instead, the strip is urged entirely towards one undercut edge of the slot.

The bottom wall of the T-slots 101 are milled flat to accommodate the bottom fixed louvre seen at the left hand side in Fig. 1 and the louvre extends into contact with the side walls 1C of the members 16 beneath the pile weatherseal strips which then seal the gaps between the fixed louvre and the walls 1C.

1 A similar arrangement is adopted to accommodate the top fixed louvre. Any rain water seeping through the joints is collected in the rain channels 16a, 18a, to be drained outside the.ventilator body onto the roof.

At the same time, the strips present a wide, flat uninterrupted pile surface in engagement with the louvre ends, sufficient to accommodate the slope of the louvres when in their closed position without leaving any substantial leakage gaps.

To this end, the end of each channel member 16-may open through the wall 1V to drain off water from the channels outside the body of the ventilator.

The louvre blades may be formed e.g. extruded from translucent material e. g.

other translucent louvre blade constructions may be used.

14 u.p.v.c. or polycarbonate.

constructions e.a. framed -

Claims (5)

CLAIMS:

1. A controllable louvred ventilator in which pile weatherseal strips seal the gaps between the louvre ends and the ventilator frame when the louvres are in their closed position, the louvres have leading and trailing edge formations which overlap one another in the closed position of the louvres and trailing edge channels which open at their ends below the pile weatherseal strips to drain water into internal water drainage channels of the frame and at least two sideby-side, pile weatherseal strips are provided having the top surfaces of their piles lying in a common plane and touching one another, the strips being of different transverse dimensions and having their T-slot mountings disposed in stepped relationship to one another.

2 which the or upward

3 which the

4 claim in A ventilator as claimed in claim 1 in louvres have plain ends without downward extensions.

A ventilator as claimed in claim 1 in louvres are extruded sections.

A ventilator as claimed in any preceding which the louvres are pivoted on axes extending between their leading and trailing edges and the louvre axes intersect the pile weatherseal strips at their respective ends, one of the side-by-side pile weather- 4 seal strips being formed in secti6ns extending between adjacent louvre pivots.

5. A controllable louvred ventilator substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

v i 11 1 Publish d 1988 at The Patent Office, State House. 66"71 High Holborn, London WC1R 4TP. Further copies may be obtained from The Patent Office, Sales Branch, St Mary Cray, Orpington. Kent BR5 3RD. Printed by MuItiplex techniques Itd. St Mary Cray, Kent. Con. 2187.