The multi-Axis sensor consists of a hexapod truss structure arranged between two plates without additional joints. The sensor is (usually) manufactured from a single piece of high-strength aluminum (3.1354) or high-strength ferritic stainless steel (1.4542).
For the sensor to function correctly, it is crucial that the end faces are not locally deformed.
A local deformation is caused, for example, if a point force Fz were applied at the center of the sensor.
The force is applied across the entire surface of the circular ring between the inner centering collar and the outer diameter. The force is also applied to the trapezoidal segments of the circular ring. The recesses between the segments are not subjected to any load.
Besides the force transmission on the circular ring, the flatness and stiffness of the connecting flange are important parameters. High-strength aluminum or tempered tool steel 24CrMo4 or C60, or high-strength stainless steel 1.4542, should be used as the material. 3D-printed plastic flanges are unsuitable!
A loose screw can cause measurement errors on the order of 10% or more.
The tolerance for the flatness of the flanges is 0.02mm.
Table 1 provides guidelines for the thickness of the connection flanges and the recommended tightening torque. If the recommended tightening torque exceeds the sensor’s rated torque, no torque should be applied through the sensor. Instead, the counter-torque should be applied directly to the flange.
The screws should have a minimum strength class of 8.8. Screws with a strength class of 10.9 are recommended for torques above 100 Nm.
When designing the flange, care should be taken to ensure that local weak points do not cause asymmetrical deformation of the surface of the force sensor.
Isolated outbreaks, such as those shown in the adjacent figure, should be avoided.
Mounting all components from one side is often only possible by designing a two-part flange.
Example for K3D110:
Adapter for Comau SMART-5 NJ-60:
Flange for K6D80:
When applying forces and moments, care must be taken to ensure that the flange plates of the 6A sensor are not deformed. In particular, when applying moments, the application should be central and symmetrical.
The image shows a local deformation of the flange plate due to an asymmetrical introduction of a moment.
The figure shows a flange for the (largely) symmetrical introduction of moments for the 6A225 sensor.
The table provides guidelines for the material thickness of the flange plates and for the tightening torques for mounting the sensors.
