This system analyzes the commutator contour and calculates geometrical characteristics, after a "filtering" process removes the slots from the original profile.

The bench references the armature shaft on V journals, reproducing the machining condition.


  • BAR TO BAR: This is the vertical gap between the two adjacent edges on adjacent bars. All such gaps are calculated and the worst case is displayed. The typical tolerance is 3 µm. Values exceeding the tolerance have a dramatic influence on motor life.

  • BAR RISE - DELTA BAR: This is the TIR of each single bar. All the TIR's are calculated and the worst case is displayed. The typical tolerance is 5 µm. The value is related to the lathes tool status and indicates when a new tool is required.

  • TIR: This is calculated considering all the bars. The typical tolerance is 10 µm. This value reveals if the shaft is bent and inidicates potential problems with the part assembly process.
  • COMMUTATOR DIAMETER: The typical tolerance is 200 µm.
  • ROUNDNESS: The typical tolerance is 5 µm.

  • Angle between corresponding commutator and stack slots (commutation): This is performed if the stack slots are straight or if the section being inspected is referenced to a face of the shaft.
  • Stack TIR.
  • Stack diameter.
  • Shaft TIR in different sections.
  • Bearing shoulder TIR.
This equipment is used along with an industrial PC E9066 Flat Panel.


The standard bench can check all the armatures in the following range:
  • Journal diameter: 3-17 mm (1/8-11/16").
  • Commutator diameter: 60 mm (2 3/8") max.
  • Stack lamination diameter: 120 mm (3 15/16") max.
  • Distance between Journals: 300 mm (11 13/16") max.
  • Special range fixtures are available on request.
Part change is user friendly exploiting the self learning retooling technique.

This technique guides the operator in repositioning all the adjustable fixture subassemblies, whose positions are detected by sensors and displayed by virtual scales.



  • Repetitive results, because the algorithms are always the same.
  • The measuring process is reproducible, because it is not influenced by the operator's judgment.
  • The measurements are obtained individually, by allowing the customer to tune the filtering parameters for every part number in an easy and clear manner.
  • The modular design allows for the implementation of subsequent standard options.
  • The self learning retooling option is a great advantage where the unit is used to randomly measure a wide range of parts.
  • Software upgrades may be downloaded on-line by customers using their individual password.
  • Worldwide service support availability.
  • Post-process features available.
  • Connectivity for use of network utilities for data transfer, printing etc.
  • Collected measurement data can be transferred in QS-stat or Excel format for customized reporting.
  • It is possible to check the comprehensive system performance in a scientific manner using a master with shape errors (that is normally supplied with the bench).
  • This measurement system exploits the experience gained on a wide range of products supplied to all the main manufacturers worldwide. This experience provides for a strong knowledge base and allows product features to grow according to common needs.
  • For the above mentioned reasons, the product is a recognized standard in its field.
  • A fixture version is available, suitable for applications with pick and place devices or robot loading

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