Conventional trimmers operate with belt drive, resulting in high belt wear due to wood dust. To reduce wear and simplify maintenance, Springer aimed to develop a novel beltless geared pivot saw arm. Therefore, the machine builder turned to Watt Drive to develop these special beltless gear units. Watt Drive designed and produced a completely new drive system for each saw. It consists of the innovative trimmer gear unit, a helical bevel geared motor, and one or two W22 motors for the main drive, depending on the configuration.
In the E-CUT 200 the saw blades are turned by centrally positioned, external electric WEG W22 motors through the pivot arms, which are uniquely implemented as beltless gear units. The individual saws are operated by electrically actuated crank mechanisms with pushrods. This electrical operation allows the motion of the individual saws to be controlled precisely, independent of temperature variations. Therefore, the novel crosscut saw arms achieve higher efficiency than comparable models with hydraulic or pneumatic drive.
The circular saws are driven by one or two four-pole W22 motors with frame size IEC 225 (model 225S/M-04). With a rated power of 37 kW each, the motors drive the input shaft of the special gear units via V-belts.
With a torque rating of 593 Nm, the special gear units have a gear ratio of 2.42 to boost the blade speed. The special gear units are specifically designed for high ambient temperatures up to +50°C and are especially well sealed for operation in dusty environments. All covers are additionally glued in place. The gear unit cases are made from nodular cast iron for especially high strength and resistance to ambient conditions, which is essential for the harsh operating conditions in the timber industry.
Each of the circular saw blades is raised and lowered by a 3 kW helical bevel geared motor equipped with forced ventilation and a brake (model KUS 60A 70 91L4 TH BR20 FL), which is controlled by a variable-speed drive. These drive units can optionally be fitted with incremental encoders.
The new beltless geared pivot arms dramatically reduce machine wear and maintenance effort. The E-CUT 200 also scores well for ease of maintenance with the new drive concept. All drive components are mounted externally, so they can be accessed easily and safely by service technicians without opening the actual trimmer.
