AU2002224644B2

AU2002224644B2 - A ventilation system for a greenhouse and the like

Info

Publication number: AU2002224644B2
Application number: AU2002224644A
Authority: AU
Inventors: Robert Strati
Original assignee: Rez Constructions Pty Ltd
Current assignee: Rez Constructions Pty Ltd
Priority date: 2000-12-22
Filing date: 2001-12-21
Publication date: 2007-03-15
Anticipated expiration: 2021-12-21

Description

WO 02/052112 PCT/AU01/01667 A VENTILATION SYSTEM FOR A GREENHOUSE AND THE LIKE TECHNICAL FIELD The present invention relates to a ventilation system for a greenhouse or the like building structure and, in particular, to a greenhouse utilizing a naturally forced air ventilation substructure to facilitate efficient circulation of air and heat throughout the greenhouse.

For ease of understanding and brevity, the present invention will be described with reference to greenhouses, although it is to be understood that the invention is not to be limited thereto but may apply to any building structure in which naturally forced air ventilation is sought.

BACKGROUND ART A problem with many naturally forced air ventilation systems operating in greenhouses is that they allow the wind to force air into the greenhouse and thus interfere with the ideal ventilating and heating conditions required within the greenhouse. Although such greenhouses are normally built to take account of the local wind conditions, variations in wind direction are not uncommon, and the cost of customising the construction of the greenhouse to account for the local wind conditions adds to the overall cost of construction.

Some commercial greenhouses utilize expensive automated ventilation systems which present a cost burden, both in purchase and in maintenance or repair. Although in those places or during those times of very low wind such automated ventilation systems are essential, automated ventilation systems need not be used in all of the circumstances in which they are presently being used, because in at least some of those circumstances, sufficient ventilation of the greenhouse may occur by constructing the greenhouse in such a way as to utilize naturally forced air ventilation. This is particularly so in regions of at least moderate wind or during periods of at least moderate wind where cost savings may be made by switching off the automated ventilation systems and WO 02/052112 PCT/AU01/01667 2 allowing the wind to draw air through specially formed ventilating substructures in the greenhouse.

Whilst some greenhouses rely exclusively on wind forced air ventilation, they do so by utilizing ventilation structures that are not controllable or, if controllable, do not allow for efficient escape of air from the greenhouse in all wind directions. Air circulation is often limited in these greenhouses because of improper location of air vents or, more likely, because of the overall structure of the greenhouse which is not amendable to efficient circulation of air therethrough.

It is an object of the present invention to overcome, or at least substantially ameliorate, the disadvantages and shortcomings of the prior art.

DISCLOSURE OF THE INVENTION It has now been found by the present inventor that efficient wind forced circulation of air, and thus heat, throughout a greenhouse may be achieved in an arch roofed greenhouse utilizing a ventilating roof substructure that comprises a central, cut-out radial portion of the arched roof. Controllable cover means, such as curtains or shutters, may be utilized to control the direction of air passage through the ventilating roof substructure of the arched roof.

According to the present invention, there is provided a ventilation system for a building requiring naturally forced air ventilation and having an arched roof structure, the system comprising: a roof substructure formed of a central, cut-out radial portion of the arched roof structure, the substructure defining a central opening in the curved face of the radial portion and an air vent opening in each one of respective opposed faces of the radial portion through which air may pass into and out of the greenhouse, and WO 02/052112 PCT/AU01/01667 3 (ii) cover means adapted for controlling the passage of air through the air vent openings.

Preferably, the cover means comprises a curtain over each one of the air vent openings.

In a further preferred form, the ventilation system includes a gutter located adjacent the apex of the radial portion.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be readily understood and put into practical effect, reference will now be made to the accompanying drawings, in which: Fig 1 is a perspective view of an arched roof structure of a greenhouse incorporating a ventilation system according to a preferred embodiment of the present invention, Fig 2 is a perspective view of a ventilating roof substructure of the arched roof structure of Fig 1 defining air vent openings for facilitating the circulation of air throughout the greenhouse, Fig 3 is a front elevational view of the arched roof structure of Fig 1 which depicts a roll-up curtain over each one of the air vent openings and a gutter therebetween, both of the roll-up curtains being fully extended, Fig 4 is a view similar to that of Fig 3 but in which both of the roll-up curtains are fully retracted so as to allow optimal air flow out of the greenhouse, Fig 5 is a view similar to that of Fig 3 but in which only one of the roll-up curtains is retracted, the other being fully extended, and Fig 6 is a view similar to that of Fig 3 but in which both of the roll-up curtains are partly retracted.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT WO 02/052112 PCT/AU01/01667 4 The arched roof structure 10 shown in the Figures 1 to 6 is mounted on posts 12 which define the four corners of the greenhouse.

The front and rear arch sections 14, 16 of the roof structure 10 are identical and comprise a bottom straight rail 18, a top arch rail 20, and a series of strengthening braces 22 linking the bottom and top rails 18, 20. The two most central braces 22a, 22b form a V-shaped construct and the V-shaped construct of front arch section 14 is connected to the V-shaped construct of rear arch section 16 by a pair of spanning rails 24, 26 to define a roof substructure formed of a central, cut-out radial portion 28 of the arched roof structure 10. A transparent, air impermeable, roof cover, such as glass, extends over each of the two segments of the arched roof structure that are on either side of the radial portion 28. Each of the opposed faces of the radial portion 28 define an air vent opening 30, 32 through which air may pass into and out of the greenhouse.

Roll-up curtains 34, 36 supported on each of the spanning rails 24, 26 can be manipulated to control the passage of air through the air vent openings 32. Manipulation of the curtains 34, 36 may be done manually or by automated means.

A gutter 38 also spans the front and rear sections 14, 16 and is located adjacent the apex or converging point of the radial portion 28. The gutter 38 is also of such strength as to support the weight of an average person, a feature necessary when that person is fitting roof covers.

Figure 3 shows the arched roof structure 10 with both of the roll-up curtains 34, 36 fully extended so as to prevent air flow into and out of the greenhouse. This may suit constant windy conditions in which the wind direction fluctuates and which may otherwise force air into the greenhouse.

Figure 4 shows the arched roof structure 10 with both of the roll-up curtains 34, 36 fully retracted so as to allow optimal air flow out of the WO 02/052112 PCT/AU01/01667 greenhouse. This may suit non-windy conditions, and allows rising heat and evaporated water to exit the greenhouse through both air vent openings 30, 32.

Figure 5 shows the arched roof structure 10 with the roll-up curtain 34 fully extended and the roll-up curtain 36 fully retracted so as to allow air flow only through the air vent opening 32. This may suit constant windy conditions in which the wind is travelling from right to left (see arrow A showing direction of wind).

Figure 6 shows the arched roof structure 10 with both of the roll-up curtains 34, 36 partly retracted so as to allow partial air flow out of the greenhouse. This may suit milder wind conditions.

It is an advantage of the present invention that the ventilation system may be retrofitted to any existing arched roof structure of a greenhouse.

It is another advantage of the present invention that it provides a centrally disposed ventilation system that allows the central axis of the arched roof to be openable on all suitable occasions.

It is yet another advantage of the present invention that it facilitates efficient circulation of air, and thus heat, throughout the greenhouse, and escape of air from the greenhouse when required in all wind conditions.

Various modifications may be made in details of design and construction without departing from the scope and ambit of the invention.

Claims

1. A ventilation system for a building requiring naturally forced air ventilation and having an arched roof structure, the system comprising: a roof substructure formed of a central, cut-out radial portion of the arched roof structure, the substructure defining a central opening in the curved face of the radial portion and an air vent opening in each one of respective opposed faces of the radial portion through which air may pass into and out of the greenhouse, and (ii) cover means adapted for controlling the passage of air through the air vent openings.

2. The ventilation system of claim 1 wherein the cover means comprises a curtain over each one of the air vent openings.

3. The ventilation system of claim 1 and including a gutter located adjacent the apex of the radial portion.