Pick-off spindles in CNC screw machines are designed to hold a part as it is cut to length and then finished. The spindle uses a collet to release the part when it is complete and then clinch a new part.
Disc Springs are compressed, collet is open
Disc Springs are uncompressed, collet is closed, work piece is clinched
When the machine is setup, the clamping force required to hold each part in the collet must be precisely calibrated to prevent the finished product from slipping (if the force is too low) or being crushed (if the force is too high). This calibration is dependent on the geometry and material of the final product. After calibration, the quality of the finished product relies on a consistent clamping force for thousands of cycles at a time.
This high degree of reliability is provided by SPIROL® Disc Springs. When the collet is opened, 16 SPIROL® Disc Springs stacked in series are compressed by a hydraulic cylinder. Each time the force from the cylinder is released, SPIROL® Disc Springs provide a consistent force to close the collet on the part.