From the early days of the development of the first combine in 1936, Claas has concentrated on developing machines specifically designed to achieve optimum performance in European conditions.
When it was launched in 1996, the Lexion set a completely new standard for combine harvester productivity and 20 years later, the current Lexion 700 and 600 ranges still set the standard for high output, cost effective harvesting performance.
2016 will see the Lexion 700 range further evolve with the introduction of a number of new features and improvements to the cleaning and residual grain separation systems, the straw chopper and electronics, including the roll-out further down the range of performance enhancing features previously only available on top-of-the-range models.
Through the further development of the systems that surround the Lexion’s long established and well proven Hybrid threshing system, this results in further increases in combine performance, operational reliability, efficiency and driver comfort.
In addition to these new features, Claas has also increased the Lexion 700 range with the addition of a new hillside MONTANA version of the Lexion 750, which like the larger Lexion 760 Montana will automatically self-level on slopes of up to 17 degrees.
Tier 4f engine power
Under the bonnet, the latest Lexion 700 series combines will from 2016 be powered by engines that are TIER 4f emission compliant. Currently the Lexion range is powered by either Mercedes Benz (780/770) or Caterpillar engines, but all these latest models will be powered by Mercedes Benz engines, with the exception of the Lexion 760 which will be powered by a 12.5 litre Perkins engine.
The top-of-the-range Lexion 780 and 770 models will be powered by the latest state-of-the-art 15.6 litre Mercedes engines, with maximum power outputs of 625hp and 585hp respectively, compared to 598hp and 551hp on current models. Lexion 750 and 740 models will be fitted with a 10.7 litre engine.
A particular feature of recent Lexion models has been the development of systems and components designed to increase performance, but use less engine power, so saving fuel and making more power available for other components.
One of the best examples of this is the Dynamic Cooling system originally introduced two years ago on the Lexion 780/770/760, and from this year will now also be fitted on the Lexion 750 and 740.
Dynamic Cooling features a variable fan drive which provides ‘cooling on demand’, so only ever provides the cooling output that is actually required by the machine. As a result, power requirement is reduced by around 15hp and up to 20hp on higher powered Lexion models.
The Dynamic Cooling package incorporates a charge-air pressure cooler, hydraulic fluid cooler and engine radiator. Unlike ‘standard’ cooling systems which are vertically mounted, with Dynamic Cooling the cooler package, complete with the variable fan and a 1.60m diameter filter, lie horizontally behind the engine in order to achieve a larger surface area.
This draws clean air from above the combine into the radiator, which is then forced downwards over the engine, before exiting through louvers in the side of the engine bay. This creates a curtain of air that flows down the side of the combine to actively prevent dust rising. This not only ensures that clean air is being continuously drawn into the engine, but that the whole engine bay area is cleaner, so reducing maintenance time.
Hybrid threshing and 4D cleaning
All five Lexion 700 models feature the well proven Claas Hybrid threshing system, which uses the highly efficient APS primary threshing system to remove the easily threshed grains, leaving the Roto Plus system to extract the remaining harder to remove grains.
On Lexion 770-740 models, the two Roto Plus rotors are each fitted with five rotor concaves, with the Lexion 780 having six, which incorporate hydraulic cover plates (‘bomb doors’) on the first two segments to alter the separation area.
With no restrictions of power from the higher horsepower engines and the Dynamic Cooling system, to ensure that the Hybrid system can work at maximum capacity especially when on sloping ground, Claas has developed the new 4D cleaning system.
For many years, the ability of the Claas 3D system to level the upper sieves when working across slopes has proved invaluable in helping maintain high output and avoid overloading the downhill side of the sieves.
The new 4D cleaning system takes this a stage further. The 4D system consists of two components – a slope dependent rotor cover plate control and automatic fan control.
On combines specified with 4D cleaning, an extra third pair of rotor cover plates is fitted to the Roto Plus rotors, which are divided in two. These are automatically adjusted according to the lateral and longitudinal angle of the combine, but with the current separation and cleaning output also taken into account.
As the combine angle changes, the cover plates on the up-hill side of the rotor is automatically opened or closed. When the combine is working directly up or down the slope, the 4D system will also automatically adjust the Jetstream fan speed dependent on the angle, reducing the wind speed when working uphill and increasing the speed on the way down, in addition to adjusting the lower sieve.
4D will help reduce losses when working on hillsides, provide increased cleaning capacity and help avoid the returns from being overloaded. If required the operator can manually shut-off the 4D system using the Cebis terminal, and when fitted to the combine 4D is also fully integrated into CEMOS AUTOMATIC.
To accommodate the potential increased capacity possible due to the higher engine power and the 4D system, the top-of-the-range Lexion 780 now features a larger, 13,500-litre capacity grain tank. The discharge rate from the tank is 130 litres/second, which means that the tank can be emptied in less than two minutes.
New chopper and residue management
An even spread of both chopped straw and chaff across the full cutting width of the combine is essential for efficient incorporation and breakdown in the soil. With cutting widths of up to 12.3m, to ensure that the Lexion 700 can handle the increased quantity of straw and chaff and ensure this is fully and evenly spread across the entire cutting width, Claas has developed a new straw chopper.
On the new straw chopper, the drum has been increased in width by 5 cm. As a result, crop flow into and through the chopper is more uniform, resulting in a more even chop length. The larger chopping drum also improves acceleration of the chaff, resulting in a wider spread pattern. Instead of being hydraulically driven, the radial spreader is now mechanically driven, which means that it maintains a consistent speed and reduces fuel consumption.
For greater operator convenience, the new straw chopper can be fully controlled from the cab. At the press of a button, the operator is able to quickly and simply change between the transport, chopping or swathing positions. Using Cebis, they are also able to hydraulically adjust the friction concave plate and the counter-knives.
Automatic Crop Flow control
The Hybrid threshing system used in the Lexion 700 is well known for being able to achieve high levels of output even when working in difficult conditions. At times like this, the threshing system works under a considerable load, so to avoid blockages and ensure that high load peaks are quickly identified, Claas has developed a new Automatic Crop Flow control for the Lexion 700.
The Crop Flow control monitors and compares the rotation speed of the engine, and the APS primary and Roto Plus secondary separation systems. Once the operator has set their preferred slip level using Cebis, when this is exceeded the Crop Flow system will alert the operator, while at the same time shutting down the cutterbar drive and feederhouse, engage the cutterbar brake, disengage the unloading auger and reducing the Cruise Pilot speed to the minimum speed.
The new Crop Flow system will have the benefit that it will give the operator confidence to push the combine and operate it at its maximum capacity, knowing that a potential blockage will be avoided and the downtime that will incur.
