Patent ID: 8904874

Claim:
An arrangement comprising an ultrasonic transmitting and receiving device and a foil extruder having at least one extrusion die, wherein the ultrasonic transmitting and receiving device is configured for measuring the transmission (T) and/or the reflection (R) of ultrasonic waves on a thin material sheet for determining the layer thickness and/or the grammage of the material sheet, the arrangement comprises: a plurality of ultrasonic transmitters; a plurality of ultrasonic receivers, wherein the number of the ultrasonic receivers corresponds to the number or the two-fold number of the ultrasonic transmitters; and one receiver electronics respectively for each of the ultrasonic receivers or a group receiver electronics respectively for a predetermined number of ultrasonic receivers; wherein at least one actuator is assigned to the extrusion die for adjusting the foil thickness, wherein the foil extruder comprises a control unit for adjusting or altering the at least one actuator, wherein the control unit receives at least one measurement value for the layer thickness and/or the grammage from the ultrasonic transmitting and receiving device, or from a control unit of the ultrasonic transmitting and receiving device, and wherein the control unit adjusts or alters the at least one actuator depending on the at least one measurement value.