Digitalisation and automation are becoming increasingly important in agriculture. The adjustment of different component groups to the millimetre is indispensable in many cases. At the same time, agricultural machinery has to withstand various conditions and perform at full capacity in difficult environments. This also applies to the installed components.
The use of hydraulics has a long tradition in agricultural machinery, and for many tasks hydraulics has been the obvious choice. However, in recent decades, electric actuator systems have proven that they can withstand vibrations, dust, or extreme temperature just as well as hydraulic equipment. And for many tasks electric actuators even perform better than hydraulics.
In 2005, LINAK® launched the LA36 – an actuator that is well-equipped for tasks in agricultural machinery, as it offers high protection classes and is extremely robust. Since then, LINAK has continued to optimise the LA36 and all other actuators and has added features to meet the high demands of the market.
High demands on the actuators
In the KRONE BiG X forage harvester, the demands on the actuator are also very high. The actuator uses kinematics to steplessly adjust the two corn conditioner rollers. On the one hand, it has to withstand the high forces acting on the rollers. On the other hand, it has to enable precise adjustment of the roller despite any high vibrations and shocks.
“With a working width of up to 10.5 metres, the harvester can chop up to 400 tonnes per hour. This requires a lot of power and also extremely robust components”, explains Jan Keuter, who is responsible for electrical design at KRONE. To him, electric adjustment in agricultural machinery is becoming increasingly important.
"Electrics competes with hydraulics. Hydraulics has always been available and is therefore the obvious solution”. However, electric actuators have also become standard in recent years. "ISOBUS and a 50-amp connection are standard on almost all machines”, Keuter adds.
As the level of automation increases, electric actuator systems can bring their advantages to bear. Jan Keuter confirms this: "If, for example, we have to move to different positions and require exact position feedback, it is usually cheaper and, above all, easier in terms of design to use an electric actuator".
This is exactly the case with the adjustment of the two corn conditioner rollers. The actuator uses kinematics to adjust the distance between two rollers. Optimal adjustment of the rollers to break up the corn kernels is only possible with the help of precise position feedback. Potentiometers built into the actuator make this possible.
Implementing complex movements
"In this case, the control of the actuator movement comes from the control system of the corn chopper”, Jan Keuter explains. However, he can imagine using an actuator with integrated control and power electronics in the future. This will bring along the advantages of saving cables and relieving the strain on the control system. LINAK offers a wide range of actuators with built-in control (IC) and power electronics. These provide numerous possibilities to meet the requirements of configurating complex movement. Among other things, there are interfaces supporting different bus systems, such as LINbus and CAN SAE J1939. Parallel movement of actuators without an external control is also possible with LINAK IC™ actuators. A further advantage is the read-out of data from the actuator.
Jan Keuter also emphasises this: "Service will play an increasingly important role in the future. That is why it is important to be able to monitor the condition of the machine. For example, the temperature in certain areas of the machine, or the number of cycles the actuator has run”.
Right above the actuator for adjusting the corn conditioner rollers is a second LINAK actuator, which adjusts the back plate of the discharge accelerator. By adjusting the back plate, the discharge spout is narrowed to enable long-distance discharge or widened for short-distance discharge. Even though the second actuator applies less force, it is still exposed to extreme vibrations.
"We test our machines and the components used, in our own validation test centre. This is also where LINAK actuators prove their quality. As a premium supplier, we only want to use products of the highest quality, and the Danish manufacturer LINAK has met this demand for many years”, Jan Keuter concludes.
