For the magnetic detection of rotational movements, rotational speed and position sensors together with measuring gears form a unit. Magnetoresistive elements in the sensor scan the structure of the ferromagnetic measuring gear in a contactless manner. The sensor generates Sin/Cos signals from this, for example. In many applications, e.g. in motors of machine tool spindles, the speed signals are interpolated to a high level. Precision measuring gears are a prerequisite for optimal signals with high quality.
Reference marks
The selection of the reference mark is determined by the size and speed of the measuring gear used, since both variables influence the forces acting on the reference mark. The following reference marks are feasible: Flag (N), tooth (Z), groove (M) or gap (G). For new designs, we recommend the use of a measuring gear with the reference marks “Z” or “G”.
Module and outer diameter
Depending on the application and the sensor used, measuring gears with different modules are used. The module is a gear tooth measure for gears and describes the relationship between the number of teeth and the pitch circle diameter of the gear. For most applications, the outer diameter of the measuring gear is decisive.
da = m • (z+2)
da = outside diameter
m = modulus
z = number of teeth
If the number of teeth is the same, the smaller the modulus, the smaller the outer diameter.
Benefits
- Various assembly variants (shrinking on, clamping, screwing on)
- Anti-rotation lock possible via keyway
- Multifunctional embodiment allows for use
- of the measuring gear as a bearing cover or shaft nut
- High flexibility in design through customer-specific production
- Highest precision through the use of the most modern rolling
- Milling machines and turning milling centres
Operational area
- Motor spindles in machine tool construction
- Rail transport technology
- Torque motors
- Vacuum pumps
