Single engine sweeping systems Transmission enables flexible deployment
Stiebel mechanical and hydrostatic transfer cases combine power with efficiency
Operating daily in uncompromising conditions, sweepers must deliver sustained, dynamic performance on the road. They need to deal with heavy-duty cleaning on crowded streets in urban and inner-city areas. Agility is the key. The answer is a winning combination of flexible driving force and compact efficiency. With this in mind, the experts at Stiebel-Getriebebau (http://www.stiebel.de/en/homepage.html) have developed a special-purpose manual transfer case model 4664. Sweepers can now switch between mechanical and hydrostatic drives according to deployment. The vehicle features a single diesel engine-instead of the previous two engines-to ensure more effective driving and operation. Overall costs are lowered by reducing weight, fuel consumption and exhaust emissions.
Mechanical drive for operating in road traffic
To travel to the next deployment area, the driver simply changes the shift position of the transfer case to "drive". The vehicle is capable of road speeds of up to 80 km/h (50 mph). Power/engine speed is then transferred directly from the diesel engine and drive transmission to the vehicle"s drive axle.
Hydrostatic operation for sweeping at optimum speeds
To start sweeping, the driver simply moves the shift position of the transmission to "distribution". The driving gear is now in an idling position. Drive power is delivered by a hydraulic motor mounted directly on the transfer case. This hydraulic motor is fed via a pump on the diesel engine"s PTO unit. Engine speed is reduced using a compact, dual-stage step-down ratio in the transfer case (up to 14.6:1 possible). This ensures that the required operating speed for sweeping-up to 10 km/h (6.2 mph)-is achieved within the optimum diesel engine speed range.
"The challenges we faced in development and implementation focused on transmission flexibility," explains Paul Hermann Schumacher, CEO of Stiebel-Getriebebau GmbH & Co. KG. "Sweepers weighing up to 13.2 tons are now equipped with a single engine to deliver outstanding adaptability. Our specialists have done a superb job, working meticulously to significantly improve drive efficiency." The Stiebel transfer case also boasts greater flexibility. It is not only the driving force in sweepers, it also comes into its own when used in other municipal vehicles that require a reduced-speed operating mode. (http://www.stiebel.de/en/applications/mobile-hydraulics/drive-engineering.html)Following on from this impressively dynamic transmission solution, the Stiebel team is already working on the next advanced drive technology (http://www.stiebel.de/en/accomplishments/gear-manufacturing.html).
Transfer cases drive, Stiebel-Getriebebau, single-engine sweeping systems
by: Stiebel Getriebebau GmbH and Co KG