Hoes and harrows are currently undergoing their renaissance. What only organic farming has been using so far has become increasingly important in conventional farms. Because, pesticides such as glyphosate are becoming increasingly controversial in weed control. In Austria, too, the chemical is already under discussion and a draft law on a glyphosate ban has been prepared. In order to successfully combat weeds, organic farmers in particular are currently relying on choppers that reach the roots of the weeds. The problem with conventional devices: they have to be set mechanically using the plate when stationary and at up to 60 points, using a spanner and foot rule. Operations that are very time consuming. For this reason, Klemens Ollmaier, Hannes Hutter and Philipp Holl from samo Maschinenbau GmbH developed the VarioCHOP system together with their project partner Roman Romstorfer. The name stands for the product range, because variable and infinite chopping modes are possible with the device. A patented invention that also delighted the DLG jury for the Agritechnica Awards and honoured the newcomers with a silver medal. The iglidur plain bearings from the motion plastics specialist igus ensure a safe and maintenance-free bearing for the movable chopping elements.
With the VarioCHOP, the processing width can be easily set manually or automatically. This way weeds are chopped more efficiently and sustainably.
The hoeing elements are exposed to harsh environmental conditions such as dust, dirt and moisture. Accordingly, the bearings must be extremely robust and must be able to withstand not only the weather but also shocks and knocks.
With maintenance-free plain bearings made of iglidur G, samo Maschinenbau can also do without additional lubricants. This prevents lubricants from getting into the soil. The plain bearings are very insensitive to dust and dirt and can be easily cleaned. Shocks and impacts are absorbed by the mounting with iglidur plain bearings .
Three young engineers from the field of agricultural technology are behind samo Maschinenbau. All grew up on Austrian farms and are intimately associated with agriculture. The passionate developers and designers came together and took over samo Maschinenbau GmbH in 2018, a classic contract manufacturer for machine tools. "As self-employed individuals we have already developed many projects up to market maturity. However, we lacked direct production. Therefore, we decided to take over samo Maschinenbau in October 2018 and combine the two skills. Now we can develop new products in a dynamic team not only on paper, but also bring them to the end customer", explains Klemens Ollmaier, one of the three Managing Partners of samo Maschinenbau GmbH
A total of 14 iglidur G plain bearings are used in the level guide of each chopping element.
The farmer sows the seeds in spring. The chopping time then begins in mid-April and continues until July. The objective of chopping: get as close to the plant as possible to reduce weed pressure and reduce manual rework. Because, a chopped soil contributes to a higher water absorption by the plant and to an improved growth of the root. Depending on the crop, there are different row spacing and chopping intervals. While some fields only need to be chopped twice, other fields use the chopper up to five times.
Since plants have a different size for each process and the soil has a different condition depending on the weather, the chopper must be reset each time. "For years we were annoyed by the tedious adjustment of the chopping elements, so we had to find a new and practical solution that would make life easier for the farmer and make chopping with centimetre accuracy, efficient and easy", says Roman Romstorfer, organic farmer and project partner of VarioCHOP. No sooner said than done, the first prototype of the modern chopper which was created in 2017, is now ready for series production at the beginning of 2020, after several prototype stages.
In parallel kinematics, the designers rely on 18 lubrication-free, lightweight plain bearings made of the all-rounder material iglidur G for each hoeing element.
The VarioCHOP consists of several chopping elements, the number of which the customer can determine themselves. Parallel kinematics make it easy to adjust the individual elements. Maintenance-free plain bearings were in demand here: "We were looking for a material that was lubrication-free, robust and cost-effective, so we opted for the iglidur plain bearings from igus", explains Klemens Ollmaier. A total of 18 iglidur plain bearings made from iglidur G tribo-polymer are used in the parallel kinematics of the chopping elements. As an all-rounder, iglidur G is extremely wear-resistant, corrosion-free and light. By dispensing with fats and oils, no lubricants get into the soil.
Another 14 plain bearings made of the same material ensure maintenance-free operation of the level guide. "iglidur G has a high permissible surface pressure and is also very attractive in price as a large bushing with a diameter of 35 millimetres. Technically the best and the most cost-effective solution that works. Thanks to a large number of tests in the in-house igus laboratory, the material has also proven itself in heavy-duty applications for years", explains Christoph Föttinger, Managing Director of plain bearing technology at igus Austria.
The plain bearings are simply pressed into the elements. They are lubrication-free, insensitive to dust and dirt and therefore ideally suited for use in agricultural machinery.
The VarioCHOP system has a response time of five seconds and is conceivable for 2 to 99-row choppers. Simply mounted at the front and rear of the tractor, users can adjust the VarioCHOP chopping elements manually by hand with a cotter pin or, even more conveniently, directly from the tractor cab. The parallel kinematics of an element is driven by a precision hydraulic cylinder, which is coupled to a steering angle sensor. This means that the farmer can set the optimum processing width directly from the cab while driving. While in the past there was still a person sitting on the rear end of the tractor to monitor the correct position of the chopper, this function can now be carried out with a camera on the VarioCHOP. In this way, adjustment errors can be completely avoided and the width can be adjusted fully automatically. For farmers who chop different fields as service providers, the VarioCHOP enables enormous savings in time and cost.
Furthermore, the user can save enormous herbicide costs with the chopper. "We ourselves tested the VarioCHOP over several seasons and in several crops in our fields and are absolutely convinced by it, which is why we submitted our invention for the Agritechnica Award," explains Romstorfer. The jury of the German Agriculture Society was immediately impressed by the concept and design of the new chopping machine. The VarioCHOP won the silver medal of the coveted prize and prevailed against a number of established agricultural machinery manufacturers. "Our goal is to promote the VarioCHOP on the market internationally in 2020, because the device has great economic potential for farmers. With igus on board as a partner, we are able to do this, because the products are available directly from stock, are of high quality and at the same time are cost-effective", says Ollmaier.
Klemens Ollmaier (right) from samo has been working with igus Austria Managing Director Christoph Föttinger in designing agricultural machinery for many years.