[0001] The present invention comprises improvements in ventilators and concerns controllable,
louvred ventilators more particularly, although not exclusively, for roof mounting.
[0002] Such roof mounted ventilators provide for natural extract ventilation and for the
exhaust of heat and smoke in the event of fire.
[0003] 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 also 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 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.
[0004] This arrangement requires that the outer faces of the louvres, when in their closed
position, extend transversely at a shallow angle relative to the lengthwise 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.
[0005] 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 closed across the strip.
[0006] 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, 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 leakage path for water running off the outside
of the louvres, into the ventilator.
[0007] 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.
[0008] 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
FIG. 3 is a section on line 3-3 in Fig. 2.
[0009] 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.
[0010] 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 16ʹ, 18ʹ (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
16ʹ, 18ʹ, of all the members 16, 18 substantially correspond with one another in cross-sectional
size and shape to interfit with the wall 12 in the manner seen in Fig. 1. The webs
or floors 16
a, 18
a of the channel members 16, 18 abut the base flange 11. The channel members 16, 18
act as internal drainage channels for water which runs off the louvres 15 into the
body part 20 of the ventilator. The other upstanding walls 16ʺ, 18ʺ 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
formed in hollow part-cylindrical (270°) formations 24 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.
[0011] The louvre end pivots 22 are provided with bearing shoulders 34 which bear directly
in the walls 16ʺ of the box and the pivot pins 22 are secured in the formations 24
by wing formations 22ʹ 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 22ʹ reach this position whereby the louvres 15 are predeterminedly
positioned between the walls 16ʺ. To secure each louvre against rotation with respect
to its pivot pins 22, the pins have splines 22ʺ which fit closely between the free
edges of the channel formation 24 of the louvre. The gaps between the louvre ends
and the walls 16ʺ are sealed with pile weatherseal strips 38
a, 38
b mounted in open-ended T-slots 100, 101 formed on the insides of the walls 16ʺ 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
38
a, 38
b so as to be inclined downwardly towards the trailing edge rain channels 32 when the
ventilator is mounted in a horizontal position.
[0012] As may be seen from Fig. 3, the pile weatherseal strips 38
a, 38
b, extend side-by-side with the top surfaces of their piles lying in a common plane
and touching one another, the upper strip 38
a having larger transverse dimensions than the lower strip 38
b 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 38
b is formed in sections, each section extending between an adjacent 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.
[0013] The sections of the strips 38
b 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 38
a, 38
b, 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 38
a, 38
b, 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.
[0014] 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 16ʺ of the members 16 beneath the pile weatherseal strips which then
seal the gaps between the fixed louvre and the walls 16ʺ. A similar arrangement is
adopted to accommodate the top fixed louvre. Any rain water seeping through the joints
is collected in the rain channels 16
a 18
a, 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.
[0015] To this end, the end of each channel member 16 may open through the wall 18ʺ to drain
off water from the channels outside the body of the ventilator.
[0016] The louvre blades may be formed e.g. extruded from translucent material e.g. u.p.v.c.
or polycarbonate. Other translucent louvre blade constructions e.g. framed constructions
may be used.
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 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.
2. A ventilator as claimed in claim 1 in which the louvres have plain ends without
downward or upward extensions.
3. A ventilator as claimed in claim 1 in which the louvres are extruded sections.
4. A ventilator as claimed in any preceding claim in 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 seal strips being formed in sections extending between adjacent louvre pivots.