133-11 Lohr, 2011-11-29

Award for load relief control for the comfort front linkage.

PRC Pressure Relief Control

The PRC Pressure Relief Control from Rexroth can be used with front linkages for all kinds of attachments such as mowers, mulchers and snow plows.

The DLG (German Agricultural Society) silver medal for 2011 goes to the convenient, efficient pressure relief control in the new Vario 700 SCR from Fendt

  • Gentle on the soil when mowing and reduces wear on the attachment
  • Comfortable, precise adaptive capability for increasing operating comfort and efficiency

Practices that enhance soil stability are gaining importance in today’s agriculture. The attachments should not only make optimal contact with the surface in all kinds of weather, they also need to be cost effective, compact and easy to operate. The PRC Pressure Relief Control from Rexroth meets this challenge with its automatic features and dynamic response. Used in the 700 series Vario SCR, Fendt received the silver medal of the German Agricultural Society (DLG) for this innovation at Agritechnica 2011.

Peaks and hollows in the field can cost tractor operators time and nerves. Using springs and chains to adjust the attachments for changing ground contours is a time-consuming process. The result is often excessive contact pressure, resulting in premature wear to the attachment. Using their vast experience with this scenario, the hydraulics specialists from Rexroth have developed a hydraulic pressure relief control. PRC works automatically and is integrated into the front linkage of the tractor, eliminating the need for springs on the attachment. The pressure relief system requires no calibration and makes do without accumulators and pressure sensors. The result is a compact, cost-effective control unit.

The key components of the PRC are the valve and position sensor, which use dynamic monitoring to actively monitor soil contours. The valve ensures even adaptive contact pressure. This is achieved by transferring part of the weight from the attachment to the tractor depending on the ground contour. In contrast to conventional manually adjustable spring/chain systems, the contact pressure continually adapts to changing conditions. The driver can conveniently set the desired contact pressure from the cabin while driving, using an operating control integrated into the terminal. The attachment then follows changing ground contours with perfect sensitivity. The benefits are seen under various soil conditions such as hilly terrain or wet subsoil as well as use of a snow plow on paved road. Since PRC provides greater load on the front axle, steering capability is increased along with safety when using the snow plow. The system can be overridden at any time for raising and lowering, then returned at the driver’s command to pressure relief with no delay.

Fendt uses the innovative load relief control in the comfort front linkage of their new 700 Vario SCR tractor series, for which they were awarded the DLG silver medal at Agritechnica 2011. From over 300 submissions from various manufacturers, a jury of non-biased experts commissioned by the DLG recognized two innovations with a gold medal and 39 with the silver medal.

Bosch Rexroth AG is one of the world’s leading specialists in the field of drive and control technologies. Under the Rexroth brand name, the company supplies more than 500,000 customers with tailored solutions for driving, controlling, and moving. Bosch Rexroth is a partner for Mobile Applications, Machinery Applications and Engineering, Factory Automation and Renewable Energies. The company provides customized solutions tailored to the needs and specifications of each individual market. As The Drive & Control Company, Bosch Rexroth develops, produces, and sells components and systems in over 80 countries. As part of the Bosch Group, Bosch Rexroth and its 34,900 associates generated approximately 5.1 billion euros in revenue in 2010.

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The Bosch Group is a leading global supplier of technology and services. In the areas of automotive and industrial technology, consumer goods, and building technology, some 285,000 associates generated sales of 47.3 billion euros in fiscal 2010. The Bosch Group comprises Robert Bosch GmbH and its more than 350 subsidiaries and regional companies in over 60 countries. If its sales and service partners are included, then Bosch is represented in roughly 150 countries. This worldwide development, manufacturing, and sales network is the foundation for further growth. Bosch spent 3.8 billion euros for research and development in 2010, and applied for over 3,800 patents worldwide. With all its products and services, Bosch enhances the quality of life by providing solutions which are both innovative and beneficial.

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Susanne Herzlieb
Maria-Theresien-Straße 23
97816 Lohr am Main
Phone: +49 9352 18-1573