The inventor of continuous generating gear grinding, Reishauer AG of Wallisellen, Switzerland, will demonstrate the RZ 160 — the machine that sets the standard for gear grinding machines in this size range. This concept is based on the successful RZ 150 series with more than 600 machines installed in plants worldwide. The RZ 160 has not only been increased in size, but also all relevant components have been adapted to handle higher loads and forces that occur when grinding larger gears. Gears with an outside diameter of 160 mm and modules up to 4 mm can be ground with the highest reliability in Reishauer’s quality.
An important focus in the design of the machine concept was adaptability to the different production requirements of numerous customers. The machine can be fitted with one or two work spindles. The version with two work spindles is used to minimize the loading times, as introduced with the Reishauer RZ 150. When grinding gears with space limitations, it might be advantageous to use the changeable profile-grinding spindle, which enables the use of a small-plated or dressable wheel to grind gears using the discontinuous profile method. Both versions of the RZ 160 can be equipped with a fixed or CNC-controlled axis for swiveling the dressing tool. With this option, the flexibility of the dressing tools can be increased since the same tool can be used for a range of gears as compared to the fixed dresser where the tools are normally workpiece specific.
Short cycle times place high demands on the automation system. Felsomat, a member of the Reishauer Group, has developed an automation system that is optimally matched to the specific requirements of the RZ 160. In combination with the Felsomat FRC600 robot cell, the machine can exploit the high productivity and is suited for small to medium lot sizes. Available options include composite checking, de-oiling, and SPC & NOK drawers.
Reishauer will be demonstrating polish grinding on a helical gear used in a truck transmission. The grinding wheel has two different sectors and compositions, one area is used to grind and remove the heat treat distortion, and the other area is used to polish the tooth surface.
The geometry of the grinding wheel is produced by conventional dressing systems. Grinding various workpieces requires a variable shift jump to reach the polish grinding sector. The shift feed rate and the shift jump can be optimized for polish grinding depending on the dressing frequency.
This process achieves a surface finish of Ra .10 µm. In addition to the improved surface, the polish ground process rounds out the edges at the transition of the workpiece flank and face. The topography of the flanks remains unchanged.
Like all Reishauer gear grinding machines, the RZ 160 has been developed exclusively without compromises for the high demands of the continuous generating gear grinding process, also known as the Reishauer style. All design characteristics that lead to the success of other Reishauer machines have been incorporated in the RZ 160. This includes the Reishauer Generating Module for highest gear quality, Reishauer LNS™ low-noise shifting technology for low gear noise emissions, polish and fine grinding for surface roughness reduction, Reishauer Twist Control™ grinding technology to create defined values for flank twist, and the Reishauer HMI for fast changeover and setup times. Visit Reishauer at Booth #2242 at Gear Expo, October 20-22, in Detroit.
