Combustion engine comprising - at least one cylinder - at least one inlet valve arranged in each cylinder - at least one exhaust valve arranged in each cylinder - at least one camshaft (20, 23) controlling the at least one inlet valve and/or the at least one exhaust valve - one crankshaft controlling the at least one camshaft (20, 23) - at least one hydraulic phase-shifting device arranged between the crankshaft and the at least one camshaft (20, 23) to change its rotational position in relation to the crankshaft to push forward or defer the at least one inlet valve's and/or the at least one exhaust valve's opening and closing times, which phase-shifting device is connected to an accumulator, in which a first piston, moveable between two end positions (77, 78) demarcates a first chamber connected to an inlet conduit through which oil may be supplied to the first chamber and which allows the accumulator to assume a first state at which the first chamber contains oil, and a second state at which at least a part of the contained oil has been supplied to the phase-shifting device 29, wherein the first piston is connected with a pressure-medium controlled cylinder adapted to impact the first piston to assume its end positions (77, 78), which end positions (77,78) correspond to the accumulator's first and second state, respectively, characterised in that the pressure-medium controlled cylinder comprises a second piston, moveable between two end positions (63,64) demarcating a first and a second chamber (73,74) in the cylinder and that the second piston is connected to a piston rod extending into the accumulator and which is connected to the first piston, and wherein the second chamber is connected with a directional valve via a third pressure-medium conduit, that the first chamber contains at least one spring element and that the directional valve is connected with a pressure medium source via an inlet conduit, wherein the directional valve may be switched between a second position to supply pressure-medium to the second space and shift the first piston towards its second end position, corresponding to a second state, and a first position where the spring element is adapted to shift the first piston towards one end positions, corresponding to the first state. - at least one cylinder - at least one inlet valve arranged in each cylinder - at least one exhaust valve arranged in each cylinder - at least one camshaft (20, 23) controlling the at least one inlet valve and/or the at least one exhaust valve - one crankshaft controlling the at least one camshaft (20, 23) - at least one hydraulic phase-shifting device arranged between the crankshaft and the at least one camshaft (20, 23) to change its rotational position in relation to the crankshaft to push forward or defer the at least one inlet valve's and/or the at least one exhaust valve's opening and closing times, which phase-shifting device is connected to an accumulator, in which a first piston, moveable between two end positions (77, 78) demarcates a first chamber connected to an inlet conduit through which oil may be supplied to the first chamber and which allows the accumulator to assume a first state at which the first chamber contains oil, and a second state at which at least a part of the contained oil has been supplied to the phase-shifting device 29, wherein the first piston is connected with a pressure-medium controlled cylinder adapted to impact the first piston to assume its end positions (77, 78), which end positions (77,78) correspond to the accumulator's first and second state, respectively, characterised in that the pressure-medium controlled cylinder comprises a second piston, moveable between two end positions (63,64) demarcating a first and a second chamber (73,74) in the cylinder and that the second piston is connected to a piston rod extending into the accumulator and which is connected to the first piston, and wherein the second chamber is connected with a directional valve via a third pressure-medium conduit, that the first chamber contains at least one spring element and that the directional valve is connected with a pressure medium source via an inlet conduit, wherein the directional valve may be switched between a second position to supply pressure-medium to the second space and shift the first piston towards its second end position, corresponding to a second state, and a first position where the spring element is adapted to shift the first piston towards one end positions, corresponding to the first state.