A working tool, in particular a soil rammer or a hammer, has two masses that may be linearly moved back and forth with respect to one another, namely a top mass which comprises a driving motor and a ramming or striking working mass which can be moved by the motor relative to the top mass by means of a crank drive and a set of springs. In order to reduce as much as possible the displacement of the top mass, an additional counterweight can be moved by the motor over at least a large part of the path of displacement of the working mass in the opposite direction thereto. The displacement of the end of the set of springs linked to the crank drive and the displacement of the counterweight are preferably offset relative to one another, with respect to the crank angle, by 180° minus a phase shift derived from the construction parameters of the set of springs.
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