PI 089-13 Lohr am Main, 2013-09-06

New size of hydrostatic compact unit A41CTU for power-split transmissions in low HP Range

A new size of the A41CTU, comprising a 110-ccm variable rotary group and a 90-ccm constant displacement rotary group, is now available for lower power ranges.

More ride comfort and greater fuel economy for small tractors

Lower fuel consumption and enhanced ride comfort: So far, this was only reserved for tractors with power ratings over 140 HP in combination with continuously variable power-split transmissions (CVT). Now Rexroth is launching a smaller model of the high-efficiency hydrostatic compact unit A41CTU to offer these benefits to tractors in the lower power range from 80 to 140 HP.

Power-split transmissions combine mechanical power transmission with a hydrostatic compact unit. The efficiency of the hydrostatic unit is a decisive factor, affecting fuel economy and enhanced comfort offered by the CVT transmission. In the upper market segments, many transmission manufacturers already rely on a new design principle introduced by Rexroth. Compared to conventional concepts comprising two swashplate rotary groups, a combination of swashplate variable rotary group and bent-axis constant-displacement rotary group in the A41CT raises both volumetric as well as mechanical-hydraulic efficiency.

The compact A41CTU has a space-saving U-shaped arrangement and is directly fitted to the diesel engine. This design makes it highly suitable for mid-range power ranges. Presented at the Agritechnica 2013 trade fair, the new hydrostatic unit series, comprising a 110-ccm variable rotary group and a 90-ccm constant displacement rotary group, now opens up these benefits to lower power ranges.

What mainly counts here is compact size and the right power for the application. The high power density results in a compact design. This is vital since the more stringent emission standards are causing greater space constraints under the hood since space must be found for the exhaust-gas after treatment components. The new 110/90 size covers power transmissions for engines up to 140 HP with two speed ranges to meet application requirements.

Besides fuel economy benefits, power-split transmissions coupled with the hydrostatic compact unit A41CTU enhance ride comfort. Travel behavior is much smoother and more comfortable since the hydrostatic compact unit offers higher starting efficiency and lower breakaway torque. As a result, there is less discontinuity when the direction of rotation is changed.

Economical, precise, safe, and energy efficient: drive and control technology from Bosch Rexroth moves machines and systems of any size. The company bundles global application experience in the market segments of Mobile Applications, Machinery Applications and Engineering, Factory Automation, and Renewable Energies to develop innovative components as well as tailored system solutions and services. Bosch Rexroth offers its customers hydraulics, electric drives and controls, pneumatics, gear technology, and linear motion and assembly technology all from one source. With locations in over 80 countries, more than 37,500 associates generated sales revenue of approximately 6.5 billion euros in 2012.

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The Bosch Group is a leading global supplier of technology and services, active in the fields of automotive technology, energy and building technology, industrial technology, and con-sumer goods. According to preliminary figures, more than 306,000 associates generated sales of 52.3 billion euros in 2012. The Bosch Group comprises Robert Bosch GmbH and its more than 350 subsidiaries and regional companies in some 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 some 4.5 billion euros for research and development in 2012, and applied for over 4,700 patents worldwide. The Bosch Group’s products and services are designed to fascinate, and to improve the quality of life by providing solutions which are both innovative and beneficial. In this way, the company offers technology worldwide that is “Invented for life.”

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Susanne Herzlieb
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