GB2510840A - A Ventilation Turret - Google Patents

Abstract

Disclosed is an air ventilation turret for ventilating a space, the turret having a passage for air between the space and an exterior. The turret comprises a plurality of vents 6, the vents 6 being formed between adjacent louvers 5 of a vertical stack 4 of louvers. Adjacent louvres 5 are entrained by a lost motion arrangement, such as flexible strips linking adjacent louvers, permitting movement between the louvres to open and or close the vents 6 formed there between. Lifting means is operatively connected to the uppermost louvre 5a to lift the louvre and hence all the entrained louvres 5 to their open positions and operable to enable the louvres 5 to be lowered by gravity to close the vents. The arrangement allows the turret to be expanded upwards to open the vents and collapsed under gravity to close the vents.

Description

A ventUation turret The present invention relates to a ventUation turret, particularly but not exclusively, a ventilation turret for ventilating a space in a building by means of natural ventilation.

Ventilation turrets are widely used for ventilating spaces in a variety of buildings such as offices, concert halls, schools, warehouses, shops, shopping mails car parks and factories. The known types of ventilation turret have a plurality of horizontally disposed louvres which can be opened and closed to control the flow of air therethrough The opening and closing of the louvres is typically achieved by pivoting the louvres about or close to their upper edge. This necessitates the provision of a complex linkage arrangement with accompanying control systems. Apart from the initial expense, the maintenance of such louvre systems also involves considerable expense. In another form, the Iouvres are fixed in the open position and a closure system is located on the interior of the louvres which can be moved between an open and a closed position to blank off the louvres as required.

The present invention seeks to provide a ventilation turret which is simpler, lighter and involves less expensive in construction and maintenance than the known types.

According to the present invention there is provided an air ventilation turret for ventilating a space, the turret having a passage for air between the space and an exterior comprisinga plurality of vents, the vents being formed between adjacent louvres of a stack of louvres, adjacent iouvres being entrained by a lost motion arrangement permitting movement between the ouvres to open and or dose the vents formed therebetween, lifting means being operatively connected to the uppermost louvre to lift the louvre and hence all the entrained louvres to their open positions and operable to enable the louvres to be lowered to close the vents.

In a preferred embodiment, the turret has a cap from which the louvres are suspended, Preferably, the turret has a base through which the turret is mounted, wherein the lowermost louvre is secured to the base 01 the turret.

In a preferred embodiment, the turret is substantiaDy cyndrical and the Iouvres are disposed with their axes substartiafly verticai in the installed condition, the louvres each comprising an annular ring.

Preferably, when a guide frame is provided, the annular rings are axiafly movable relative to the guide frame.

The guide frame may comprise a first movable part secured to the cap and being movably mounted relative to a fixed frame part fixed relative to the base part.

In a preferred embodiment, the lost motion means comprises a plurailty of flexible strips joining adjacent Iouvres. In aFternative embodiments, the ost motion means may comprise an insect barrier enclosing all of the vents the connections between adjacent louvres being provided by the insect barrier! or may comprise a flexible particle filter enclosing all of the vents, the connections between adjacent louvres been provided by the particle filter. Preferably, the insect barrier or particle filter may be readily removed from the turret for cleaning, servicing or replacement. In an alternative form, the lost motion means is provided by a projection or pin on a louvre engageable in a slot or groove of predetermined length in an adjacent louvre Preferably, the Iouvres are formed of aluminium or a synthetic plastics material.

Preferably, the annular rings are shaped to extend downwardly in the radially outermost direction to deflect rainwater.

In a preferred embodiment, the lifting means is powered by an electric motor responsive to one or more control devices, such as a rain sensor, temperature sensor. wind speed sensor and air quality sensors.

A preferred embodiment of the present invention will now be described by way of example with reference to the accompanying drawings in which:-Figure 1 shows a turret according to the invention in the dosed position, Figure 2 shows a side view of the turret in the extended, open position, Figure 3 shows a cross-section through the turret in the extended open position, Figure 4 shows a perspective sectional view of the turret in the extended open position, Figure 5 shows a perspective sectional view of the turret in the dosed position, arid Figure 6 shows a sectional side view of the turret in the closed posiUon.

Referring now to the drawings, Figures 1 and 2 show a verithation turret for mounting on a roof of a building such as an office, schools, shops, shopping malls, warehouses and factories to the exterior open air. Figure 1 shows the turret in a retracted closed position and Figure 2 shows the turret in an extended open position to enable ventHation to take place. In this embodiment, the turret is essentiafly cyhndrical and is niended to be mounted with ts cylindrical axis in the verhcal direction.

The turret has a base 2 by which the turret is mounted to the roof of a buHding and enclosed at its upper side by a cap 3. Between the cap 3 and the base 2 there is disposed a stack 4 of nine louvres 5, each formed of an annular ring of aIuminum or a synthetic plastics or composite material At least the radially outermost part of each louvre 5 is inclined downwardly to provide a run off path for rainwater etc. In the position illustrated in Figure 1, the turret is in the retracted position with the louvres 5 all in contact to close vents 6 formed therebetween and hence close the turret against the flow-through of air. In the extended position of the turret as shown in Figure 2, vents 6 are formed between adjacent louvres to enable air to flow to and from the interior space as indicated by the arrows 6.

Referring now to Figures 3 and 4 also, these figures show a cross-sectional view through the turret. It can be seen that the cap 3 has a slight conical profile designed to enable rain water or snow to run off the turret without entering the interior of the building. The cap 3 has a downturned peripheral rim which assists in deflecting rain away from the vents 6.

The turret has a guide frame 7 which consists of a fixed lower part 8 which is secured to the base 2 and a movable upper part 9 which is movable relative to the fixed part B in a vertical direction between the extended position shown in Figures 3 and 4 and the retracted closed position shown in Figures 5 and 6. Each frame part consists of upper and lower annular rings 10, 11 and 12, 13 respectively joined by a plurality of vertical struts 15. 14 respectively, disposed equidistantly about the circumference of the rings.

The movable part is a close sliding fit in the fixed part. The Iouvres 5 are located by the guide frame 7 so as to be constrained for movement in the vertical direction, the guide frame essentially preventing lateral movement of the louvres.

It can be seen in Figures 5 and 6, that when the turret is in the retracted position the Icuvres 5 are all contiguous so that the turret is essentiafly dosed to the passage of air.

Figures 3 and 4 show the vents 6 in the fully open position. The louvres 5 are entrained together by flexible straps (not shown) connecting adjacent louvres, a plurality of the straps, preferably 3 or 5, being disposed about the periphery of each louvre.

In operation, the turret is movable from the closed position shown in Figures 5 and 6 to the open position shown in Figures 3 and 4 by a lifting arrangement (rot shown) which raises the movable frame part 9 which is in contact with the cap 3. The uppermost louvre 5a is connected to the cap 3 by a plurality of said straps so that as the cap is raised a vent 6 is formed between the cap 3 and the uppermost louvre 5a. Further movement of the movable guide frame part 9 causes the uppermost louvre 5a to raise the louvre 5 immediately beneath it by an amount determthed by the flexible straps to create a further vent 6. As the movable frame 9 and cap 3 is moved further to the extended position it can be seen that successive louvres 5 are raised by the entraining straps to create further vents until all the louvres 5 are spaced apart with the vents 6 formed therebetween. The lowemiost ouvre 5b is secured through flexible straps to the base 2 so that when all the straps are fully extended the maximum extension of the turret is achieved.

The operation of the lifting means is reversed to return the turret to the closed position and as the movable frame part 9 is lowered, the weight of the louvres 5 enables them to lower under gravity, the lowest vent 6b being closed first and the succeeding vents 6 being closed successively until finaHy as the turret is fully retracted the vents between the uppermost louvre 5a and the cap 3 is closed.

In one embodiment, the Ufting arrangement comprises a reversible electric motor driving a lifting arrangement in the form of a screw thread or screw jack. Operation of the motor may be achieved manually but it may also be automatically controlled in dependence upon the function of a number of sensors such as rain sensor, temperature sensor. wind speed sensor and air quality sensor. The air quaflty sensor may be adapted to sense carbon dioxide, carbon monoxide or other undesirable gas. The sensors may also include smoke detectors as part of a fire alarm system.

in a further development, the vents may all be enclosed by an insect barrier and the insect barrier may be formed of a flexible material which also forms of the lost motion means to control the movement of the louvres. In an alternative arrangement the lost motion means may be formed by a flexible particle filter enclosing all of the vents. In yet another embodiment, the lost motion means may comprise a projection on a louvre engageable in a slot of predetermined length in an adjacent louvre.

Although the embodiment described is essentially cylindrical, the shape of the turret in plan view can be square, rectangular or even a non-uniform shape. Further, although shown with the louvres disposed essentially horizontally, in an alternative embodiment for use on sloping roofs, the louvres may be inclined at an angle to match the slope of the roof although the axis of the turret and direction of movement of the ouvres remains vertical.

The described embodiment is primarily intended for natural ventilation in which the heat in rising air forms the flow path of the air through and out of the turret. However, it is envisaged that mechanical assistance to increase the airflow, in the form of a fan, may be provided in the turret. The fan could be reversible to both draw air out of the interior space or to draw fresh air in.

Although described as venting a space in a building, it will be understood that the present invention is applicable to any space which may need ventilation such as tunnels. The embodiment described is particularly efficacious for a natura! ventilation turret, and relies on gravity to lower the louvres. aiding simplicity of construction, this requires the direction of movement of the louvres to be vertical or close to vertical. However, particularly when the lifting means is mechanically driven to both extend and retract the louvres, the louvres can be disposed in any desired orientation, such as vertical, when the turret is mounted on a vertical wall, with the axis of movement of the louvres being horizontal.