An internal combustion engine with a power take-off device, comprising: - at least two pairs of transfer mechanisms coupled to engine pistons, a number of such transfer mechanisms being equal to a number of the engine pistons, each transfer mechanism being adapted to convert reciprocating motion of the corresponding engine piston into a rotary motion of a corresponding power take-off shaft, each transfer mechanism comprising: - a rotation setting mechanism mounted on an axle which is connected to the piston to allow vertical reciprocal motion coordinated with the motion of the piston, the rotation setting mechanism comprising a transfer component which has an annular lower end surface defining at least one continuous wavelike guiding track formed by a guiding contact path having symmetrically positioned pairs of protrusions and depressions; and - at least one runner in a fixed vertical position and configured for traveling the corresponding guiding contact path along a horizontal circular trajectory during the reciprocal vertical motion of the transfer components thereby transferring the rotation to the corresponding power take-off shaft, each runner comprising a pair of bearings symmetrically installed on a horizontal axle which is rigidly secured to the power take-off shaft, a number of the runners corresponding to a number of the guiding contact paths; - a horizontal-movement coordinator connecting adjacent transfer mechanisms of the pairs and comprising a series of gear wheels each of which is rigidly secured to the corresponding power take-off shaft, the gear wheels being in the same plane and successively linked with one another through a gear clutch forming a closed structure; and - a vertical-movement coordinator enabling an antiphase reciprocal vertical motion of the transfer components in each pair of the transfer mechanisms; wherein the vertical-movement coordinator is formed by an articulated linkage comprising a central rocker and two symmetrical same-length connecting rods pivotably secured with respect to the corresponding rotation setting mechanism. - at least two pairs of transfer mechanisms coupled to engine pistons, a number of such transfer mechanisms being equal to a number of the engine pistons, each transfer mechanism being adapted to convert reciprocating motion of the corresponding engine piston into a rotary motion of a corresponding power take-off shaft, each transfer mechanism comprising: - a rotation setting mechanism mounted on an axle which is connected to the piston to allow vertical reciprocal motion coordinated with the motion of the piston, the rotation setting mechanism comprising a transfer component which has an annular lower end surface defining at least one continuous wavelike guiding track formed by a guiding contact path having symmetrically positioned pairs of protrusions and depressions; and - at least one runner in a fixed vertical position and configured for traveling the corresponding guiding contact path along a horizontal circular trajectory during the reciprocal vertical motion of the transfer components thereby transferring the rotation to the corresponding power take-off shaft, each runner comprising a pair of bearings symmetrically installed on a horizontal axle which is rigidly secured to the power take-off shaft, a number of the runners corresponding to a number of the guiding contact paths; - a horizontal-movement coordinator connecting adjacent transfer mechanisms of the pairs and comprising a series of gear wheels each of which is rigidly secured to the corresponding power take-off shaft, the gear wheels being in the same plane and successively linked with one another through a gear clutch forming a closed structure; and - a vertical-movement coordinator enabling an antiphase reciprocal vertical motion of the transfer components in each pair of the transfer mechanisms; wherein the vertical-movement coordinator is formed by an articulated linkage comprising a central rocker and two symmetrical same-length connecting rods pivotably secured with respect to the corresponding rotation setting mechanism.