Dynamic Fastener Sorting


The dynamic sorting system for screws works with the continuous motion of a rotary table and offers the possibility of testing up to 180 pieces per minute. With different measuring modules the optical tests as well as the crack detection and other geometrical functions can be checked.


To test the screw, a spike is inserted in the key hole and moved synchronically so the depth can be tested.

If the screw passes the fixed sender/receiver station, it will be measured and the result is sent to the PC. The precision of the sender/receiver system is about ± 0,3mm.

Crack Detection:

Using a feed system, the screws are transported in relieves on the border of a rotary table. Reaching the test station, the screws will be set in rotation by two friction belts. Starting the measurement the probe will move synchronous to the screw.

Passing the detection system the screws rotate with a speed of about 800 rpm. Therefore there is a minimum of 3 rotations of each screw during the measurement to ensure a high certainity in the testing result.

After the measurement cycle the probe returns to the start position. The result is stored in a PLC memory register in relation to the position. The accepted parts will be blown out and the not accepted parts will reach a mechanical output.




Image Control System:

With the image control different criterias of sorting can be realised:
· Head diameter
· Height of the head
· Washer present
· Diameter Flange
· Thread present or not
· Thread diameter (min, max)
· Thread pitch
· Thread length
· Length complete
· Shape of shaft endit


Instrument Parameters & Settings:

Test principle: Eddy current
Filter: On / Off for elimination of disturbances
Velocity: Slow / Normal / Fast. Internal filter for compensation of background noise and runout
Sensitivity: 0 – 100% gain control of the crack signal
Frequency: 20 KHz / 50 KHz / 80 KHz
Trigger: Internal / external test start signalInternal: By part proximity
External: Via timed PLC controller
Status: Accept / Reject. LCD display of results after each testcycle. Auto control of potential free output for external gating
Probe test: LED indicator lights for
– Probe Liftoff (OK/Out of limits)
– Probe Error (Probe defect)
– Cable Error (Cable defect)



The system consists of:

  • Machine base
  • Crack detection
  • Image control
  • Key depth
  • Maximum head diameter
  • Thread control 360°
  • Chute lane
  • Accepted part output
  • Not accepted part output



For the feeding of the parts the following components are available:

  • Storage bin
  • Vibrator conveyor
  • Step conveyor
  • Level transportation

For packaging we offer:

  • KLT-packaging
  • Box-packaging
  • Feeder for packaging