Ridder Drive Systems
3846 AX Harderwijk
Tel: +31 341 416 854
Fax: +31 341 416 611
Maintaining the ideal conditions inside a greenhouse wouldn't be possible without effective ventilation. One way this can be achieved is by the controlled opening and closing of air vents. This allows the flow of heat, moisture and CO2 in the greenhouse to be manipulated. Various ventilation systems are possible depending on the type of greenhouse. A greenhouse can be ventilated through ridge vents and sidewall vents, either operated manually or controlled by a climate computer.
Our ventilation drive systems can be used in glass greenhouses, such as Venlo, open roof and wide-span greenhouses, as well as various poly greenhouses. The following diagram shows which drive system is suitable for which type of greenhouse:
Below you can see how our drive technology can be used for ventilation purposes:
Truss-rail ventilation is most commonly used in glass greenhouses, such as Venlo and open roof greenhouses. This system uses a moving push-pull tube, which is connected to the air vents with push rods. Since the push-pull tube is located exactly above the greenhouse truss, shade is minimized. Ridder offers a wide range of reliable rack drives and motor gearboxes for this system.
Direct ventilation systems are used extensively in both glass and poly greenhouses. In ventilation systems with continuous air vents, the air vents are opened and closed directly by the rack drives. A direct drive system uses one motor gearbox for each air vent.
In an open roof greenhouse, the vents can be opened or closed with a truss-rail system or with rack drives fitted directly to both roof sides. It is also possible to drive one bay directly or multiple bays indirectly with a single motor gearbox. Most open roof greenhouses require racks in a non-standard length and bow radius. We'd be happy to advise you on which design will best suit your needs.
Indirect ventilation systems are mainly used in wide-span greenhouses. An indirect drive system drives multiple air vents with one motor gearbox. To open as many air vents with as few motor gearboxes as possible, the drive systems are combined with additional worm wheel gearboxes or other gear units. Indirect systems are not only used to open ridge air vents, but also to open and close sidewall vents in greenhouses.
Poly greenhouses can also be ventilated by opening and closing the sidewalls or through openings along the ridge. The less space the system takes up, the higher the ventilation rate and the better the crop yields will be. That's why many poly greenhouses use roller systems, which wind the poly film onto a winding tube. Direct ventilation roller systems are operated directly by cardan shafts or RW motor gearboxes.
An indirect ventilation roller system uses several gearboxes to drive several winding tubes with one motor gearbox. A major advantage of this indirect system is that a large area can be ventilated with a minimum number of motor gearboxes. This reduces the total investment cost.
The first Venlo greenhouses used swinging ventilation systems. In this system, the air vent is connected to a 'swinging' push-pull tube with push rods. This push-pull tube is positioned in the middle of a greenhouse section. Ridder offers a wide range of rack drives and motor gearboxes for this system.
Deciding which motor gearbox and drive units will best suit your needs depends on various factors, such as the type of greenhouse, the size of the greenhouse and the ambient climate conditions. Our website allows you to make system calculations for your greenhouse project, ensuring that you'll always purchase the right drive systems. If you're unfamiliar with these calculations models, we'd be happy to assist you or help you choose the right system.
Please use the form below to ask questions about our products, this website or other Ridder-related matters. This form is not suitable for placing orders. If you wish to place an order, please contact our Sales department.
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|Truss-rail ventilation: with rack drive unit around the column|
|Truss-rail ventilation: with rack drive unit at the truss|
|Truss-rail ventilation: with rack drive unit at the truss, directly driven by motor gearbox|
|Truss-rail ventilation: double continuous, with rack drive unit around the column|
|Continuous roll up ventilation: direct|
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