CTI Mag: HOERBIGER SlimLINE creates Space for Hybrid Drives
Worldwide demand for advanced hybrid technologies for vehicles is growingunabated. These technologies offer a combination of high range, low fuel consumption, and minimal emissions. At the same time, modern combustion engine-based drivetrains leave little room for the integration of additional necessary components. The innovative design of the HOERBIGER SlimLINE synchronizer saves installation space as well as weight and opens up valuable design freedom for hybrid vehicles. Transmission manufacturers can utilize the extra space for an additional electric motor, for example.
Dipl. Ing. Ottmar Back, Head of Product Line Synchronizers, HOERBIGER Antriebstechnik Holding GmbH
Issue: #December 2017
Legislators around the globe are passing tougher limits on trafficrelated emissions and greenhouse gases. The USA require manufacturers to cut average CO2 emissions of their passenger cars to 121 grams per kilometer by 2010, China is pondering a figure of 117 g/km, and Japan has set an average value of 105 g/km. The European Union has adopted one of the strictest policies, seeking to reduce emissions from presently 120 g/km to 95 g/km by 2021. Diesel or gasoline engines will be hard-pressed to reach these levels solely through optimizations within the engine, and they have no chance to satisfy China’s requirements for so-called new energy vehicles.
Diesel and gasoline engines are in need of additional solutions to meet more stringent efficiency demands. Worldwide, demand for hybrid technologies continues to grow. They play an important role in reducing emissions, without requiring compromises from drivers in terms of range, cost, charging time or infrastructure. Hybrid drives will constitute important bridge technologies in the coming years until allelectric vehicles have become widely established. The efforts of automakers continue to center around the economical implementation of lightweight designs and enhanced performance.
With the SlimLINE, HOERBIGER developed an innovative synchronizer that saves installation space and weight, thereby gaining room for additionally required components in hybrid vehicles.
Reduced installation space and decreased weight
Incorporating the benefits of hybrid drives into vehicles is a complex task for developers. They must find a way to integrate an electric motor in the tight space between the combustion engine and the transmission system. Thanks to the HOERBIGER SlimLINE, this task will become easier: Each installed synchronizer saves as much as seven millimeters in length, i.e. axially, where every millimeter counts. As a result, transmissions can have an overall shorter design in the future. This applies equally to dual-clutch transmissions, automated systems and traditional manual shift transmissions. Moreover, the HOERBIGER SlimLINE offers significant weight advantages.
Innovative shortened design opens up design freedom
HOERBIGER completely redeveloped the existing sleeve/hub system and its pre-synchronization elements. Special spring washers, which are integrated into the hub underneath the outer teeth, are considered revolutionary. They replace the previously necessary detents. While the functional principle remains unchanged, the technical implementation is different: In a first step, the marginally modified sleeve acts on the overlapping spring washer element, causing the element – instead of the formerly used detents – to be pressed against the synchronizer ring or blocker ring. Once this pre-synchronization stage is complete, further force build-up causes the spring to contract radially inwardly. This allows the sleeve to glide across the synchronizer ring as usual.
Thanks to the innovative design, recesses for the detents on the hub are no longer necessary. Without these “gaps” the hub can be built significantly narrower and with thinner wall thicknesses.