Products Hydraulic Hybrid Power Train (HHPT) System Hybra-Drive Systems, LLC (HDS) is developing a novel Hydraulic Hybrid Power Train (HHPT) for the light and medium truck markets. Like other hybrid power train concepts, the HDS HHPT is an energy management system that decouples the demand for power from the generation of power, thereby providing the vehicle designer the opportunity to optimize overall vehicle performance. In so doing, it becomes possible to deliver a truck that improves fuel economy by upwards of 60% and reduces emissions by upwards of 90% while maintaining a platform that costs the same, weighs the same, and has the same cargo capacity as existing trucks. The HHPT is conceptually similar to electric hybrid vehicles (such as the Toyota Prius). The most fundamental difference is that unlike electric hybrids, which store energy in the form of electrical power (thereby requiring a power conversion to both use and store the energy), hydraulic hybrids store energy in the form of pressurized fluid (which can be used without power conversion). Hydraulic hybrids also offer several significant advantages as compared to electric hybrids:   Variable Displacement Internal Gear Pump A component of HHPT, the variable displacement gear pump/motor, has become a hit in the marketplace in its own right. It’s a quick-to-market, incremental improvement replacement product. The  simplicity of its design makes it easier and less costly than  existing technology (i.e., vane and piston pumps) to manufacture and repair. Its smaller size and lighter weight design make it easier to package, a real benefit in an industry where consumers are demanding more payload capacity and better efficiency       ©2006 Hybra-Drive Systems, LLC All Rights Reserved info@hybra-drive.com bepiotter@gmail.com