Jun 25, 2013
A new, dynamic shading system that uses the power of the sun
Behind every innovative product is a good idea – which is based on a partnership between specialists having a forward-looking attitude – a principle that Contechma, Penn Textile Solutions and KARL MAYER have also used to great success with their joint project. The partners developed an elastic screening system which maintains a constant climate and, thus, optimum conditions for plant growing in greenhouses. OMBRA-DLS® is the name of this innovation which is produced on a raschel machine with magazine weft insertion facility. When growing plants under glass, it is extremely important to maintain the correct climate inside the greenhouse. Factors such as light, moisture and temperature have a pronounced effect on the quality of the plants and plant yields. Uncontrolled fluctuations put stress on the plants immediately. A constant level of light in the greenhouse, or one which can be adjusted as required, is one of the basic requirements for maximising plant yields. In 2009, Leo Jasper, managing director of the Contechma B.V., came up with the idea of developing an elastic screening system that would enable the light to be adjusted flexibly. Working with his company he first of all determined the requirements of dynamic light-managing systems. A strategic marketing and business plan was then drawn up. The path from the initial idea to the new, innovative product could only be taken successfully by working with the right partners. Contechma therefore looked for companies with a customer-oriented and project-based set-up, which would be prepared to cooperate, and which would be open to the ideas of everyone involved in the project. The focus of the cooperative venture was to produce a saleable product, not to generate profit at any price. OMBRA-DLS® is a textile shading solution which not only keeps the sun at bay, it also uses its energy in a targeted way. It is based on the concept of the elasticity of a UV-resistant textile net made from slit-film yarns. The permeability of OMBRA-DLS® is automatically adjusted in relation to the amount of sunlight by stretching and relaxing the screen and this regulates the amount of light that can penetrate – a principle that is also used for providing thermal insulation during the night, for example. The outer surface of OMBRA-DLS® is also coated with metal to optimise its interaction with the sun. The result is continuous light penetration for optimum climate management, without any draughts or uncontrolled air streams. This enables the factors of light and heat to be adjusted accurately to suit the type and stage of growth of the plants in greenhouses – making an important contribution to increasing crop yields. What is more, OMBRA-DLS® is cheaper and reacts more quickly than comparable screening systems, which operate with two or more shading systems or screens. The results of trials carried out on this new screen showed that constant light levels could be maintained in the greenhouse using OMBRA-DLS®, even on sunny days. Tests carried out on the new screen in a test greenhouse in Honselersdijk, in which a commercial grower grew peace lilies, gave some excellent results. Independent experts said that the root system was better, the stems stronger, the leaves greener and without blemishes, and there were more flowers. Furthermore, energy consumption was also lower. OMBRA-DLS® can also be used in the home and contract sector.
Step by step towards success
Technical textiles are usually customised products and the OMBRA-DLS® project was one that presented particular challenges. The first knitting trials began in 2009 in KARL MAYER MALIMO’s technical centre. Problems quickly came to light during the tests and the potential for optimising the processing parameters and construction of the first prototypes became clear. “Especially difficult was inserting the weft yarns in a specific way,” remembers Markus Regenstein, the managing director of Penn Textile Solutions. Processing tape yarns as the weft on its weft insertion knitting machine presented a new challenge to KARL MAYER. Although using these narrow tapes as the zero inlays has been nothing out of the ordinary for some time now, the tests that had to be carried out now meant that special component groups had to be fitted and the knitting elements had to be modified. The construction of the tapes also had to be changed. To ensure that the metallised side of the tapes was fixed on the surface during warp knitting, they had to be folded before being processed – and a special nozzle was used to do this. KARL MAYER worked with the tape manufacturer to come up with an appropriate solution. The machine also had to be modified so that UV-resistant elastic yarn could be incorporated as the knitting yarn. The process of optimising the textile and machine technology was carried out step by step until the end product met all the requirements laid down by Leo Jasper. All the partners in the project worked closely on the iterative process under the guidance of KARL MAYER.