Gear grinding process: machine ergonomics and design

When developing the G 160 gear grinding machine, particular attention has been paid to ergonomics. All needs of the machine engineers for operating, setting and servicing the machine were carefully respected. Changing tools is simplified by moving the main columns Y-axis and the tool spindle very near to the operator’s door. In this way, the wheel flange comes right in front of the operator and the reach into the machine to access the grinding wheel is very short. The same applies to the dresser, which is located next to the operator’s door.

A secondary loading door provides access to the two work-spindles when retracted into a loading position. This is where clamping fixtures, including tailstock centers, are changed and meshing sensors get adjusted. The loading and unloading interface is designed to attach a variety of external loading system, ranging from simple pickand-place to flexible robot systems. To avoid sacrificing cycle time by the loading system, double-grippers are used for cycles faster than 20 seconds. Cycle times down to 8 seconds can still be reached at full productivity by using an internal scara loader.

All mechanical, fluid and electrical components are easily accessible for service or maintenance either from outside the machine or just by opening a door to the service isle between machine and electrical box. All built-in motors and encoders have separate covers to provide access if needed. All these features fit into an attractive, incredibly small total floor space.

Finally, the same unique concept is also available on the SG 160 SKYGRIND machine, enabling the newly developed, patented dry grinding technology. On this machine, the process is split in two main passes: roughing and finishing.

For the roughing process skive hobbing is implied, whereas worm grinding is used for the finishing process. The SG 160 SKYGRIND gear grinding machine removes the majority of the stock allowance with the first pass using a hobbing tool, which has the advantage of not heating the workpiece excessively.

Subsequently, with the second finishing pass, a grinding wheel removes the remaining stock without causing problems of overheating the workpiece, therefore resulting in a completely dry process.

The additional advantages are self-evident:

  • The overall cost of consumables and the total investment are significantly reduced because of the lack of oil and all installation connected to it (pumps, tanks, filtration, chiller, oil mist extraction, and many more);
  •  The footprint is much smaller because many external units are no more necessary;
  •  The health of workers and the environmental impact of the production are significantly improved.

Summing up, Samputensili is now making a major step forward in gear grinding by presenting the G 160 gear grinding machine and its “green” sister SG 160 SKYGRIND. Developing these new machines has been very challenging for all those involved, but the partnership built with major automotive and industrial companies and the continuous positive feedbacks demonstrate that these concepts are now proven and accepted.

Workpiece diameter, max. mm 160
Module range 1.0-3.0
Worpiece length, max. mm 300
Face width, max mm 180
Helix angle degree +95°/-45°
Grinding wheel dia. mm 275 max 210 min
Grinding wheel width mm 100
Grinding speed, max. m/s 80
Dressing tool dia. mm 123
Machine dimensions LxWxH mm 3,275×2,200×2,285
Controls Siemens Sinumerik 840 D sl