The invention discloses a rotary telescopic combined oil cylinder. The rotary telescopic combined oil cylinder comprises a
telescopic cylinder body and a rotary cylinder body; the telescopic cylinderbody comprises a first cylinder
barrel and a telescopic
piston rod; the rotary cylinder body comprises a second cylinder
barrel, a spiral
piston and a rotary transmission rod; two oil cavities are arranged in the cylinder
barrel of the
telescopic cylinder body and the cylinder barrel of the rotary cylinder body respectively, and the cylinder barrels are provided with corresponding oil ports correspondingly; one end of a rotary transmission rod is rotationally installed in the rotary cylinder body, and the other end of the rotary transmission rod penetrates into the interior of the first cylinder barrel; an outer circumferential part of a spiral
piston is in threaded connection with an inner circumferential part of the second cylinder barrel, the inner
peripheral part is in threaded connection with the rotary transmission rod, and the spiral direction of the outer
peripheral part of the spiral piston is opposite to the spiral direction of a
spiral line of the inner
peripheral part; anda
blind hole is formed in the telescopic
piston rod, a peripheral part of the hole wall of the
blind hole is in transmission connection with the rotary transmission rod through a spline so that the rotary transmission rod can drive the telescopic
piston rod to rotate, and the telescopic
piston rod can move in the axial direction relative to the rotary transmission rod. According to the rotary telescopic combined oil cylinder, enough steering resistance moment can be provided, steering and suspension expansion can be realized, and meanwhile, the space arrangement of a whole vehicle can be compact.