Device for registering the brake application forces between a brake member and a brake rotor of a disc or drum brake

In an apparatus having a brake body and a brake rotor of a disc brake or drum brake, the improvement comprising:

• a multi-layer measuring film inserted between the brake body and the brake rotor;
• said multi-layer measuring film including
• a sensor layer with a pressure-dependent changing electrical property;
• said sensor layer having two electrically conductive layers connected to an evaluation device such that the evaluation device determines clamping forces between the brake body and the brake rotor from the electrical property of the sensor layer;
• and
• two electrode layers connected to the evaluation device, the evaluation device determining film capacitance between the electrode layers and therefrom a magnitude of an area of the sensor layer that is exposed to pressurization from the clamping forces between the brake body and the brake rotor.

An apparatus comprising:

• a brake body and a brake rotor of a disc brake or drum brake supported so as to be pressed together;
• and
• a multi-layer measuring film inserted between the brake body and the brake rotor;
• said multi-layer measuring film including a sensor layer with a pressure-dependent changing electrical property;
• said sensor layer having two electrically conductive layers connected with an evaluation device such that the evaluation device determines clamping forces between the brake body and the brake rotor from the electrical properties of the sensor layer affected by the clamping forces;
• and
• two electrode layers connected to the evaluation device, the evaluation device determining film capacitance between the electrode layers and determining therefrom an area of the sensor layer that is exposed to pressurization from the clamping forces between the brake body and the brake rotor.