Battery operated electric motor in a work apparatus

An electric motor as a drive motor in a work apparatus having an energy source, said electric motor comprising:

• a rotor defining a rotational position;
• an evaluation unit having a plurality of inputs;
• an arrangement of windings configured to drive said rotor;
• said windings being configured to connect to the energy source in such a manner that a load current flows through said windings and a torque which drives said rotor is generated;
• said windings having respective electric circuits and each of said electric circuits including a potential point whereat voltages (UL, UG) of different magnitude are present during operation of the electric motor;
• adaptation devices connected to corresponding ones of said potential points;
• said respective electric circuits each having a resistor configured for detecting said load current during operation of the electric motor;
• said resistor being further configured such that said load current flowing through said resistor leads to a voltage drop across said resistor and forms a load voltage (UL) corresponding to said load current;
• said load voltage (UL) being a first voltage of said voltages and having a magnitude in the range of millivolts;
• said voltages (UL, UG) further include a second voltage (UG) configured as a generator voltage and having a magnitude in the range of a plurality of volts;
• each of said electric circuits being configured to supply said voltages (UL, UG) as operating signals to corresponding ones of said inputs of said evaluation unit via corresponding ones of said adaptation devices;
• the voltages (UL, UG) of each one of said potential points being applied as said operating signals to one and the same input of said evaluation unit;
• the adaptation device of each of said circuits being configured to be operable in a first adaptation stage of high sensitivity in an amplifying manner and a second adaptation stage of low sensitivity in an attenuating manner or with a lower or no gain and to be switchable between said stages;
• a drive circuit for the adaptation device of each of the electric circuits;
• said drive circuit being configured to operate in dependence upon the rotational position of said rotor;
• and,
• said drive circuit switching the adaptation device of each of said electric circuits into one of said first adaptation stage of high sensitivity and said second adaptation stage of low sensitivity in dependence upon said rotational position of said rotor wherein the adaptation device is switched into said first adaption stage for processing said load voltage (UL) via the same input of said evaluation unit;
• and, the adaptation device is switched into said second adaptation stage for processing the generator voltage (UG) via the same input of said evaluation unit.