Steering unit for conveying devices on wheels such as beds, stretchers or trolleys comprising a wheel unit for conveying devices on wheels such as beds, stretchers or trolleys comprising: a base structure designed to be mounted on a conveying device on wheels and a wheel mounted on a supporting element in such a way as to rotate about a relative axis of rotation, wherein the supporting element is mounted on the base structure in such a way as to rotate about an orientation axis positioned transversely to the axis of rotation of the wheel to allow the orientation of the wheel and its axis of rotation about the orientation axis, wherein the steering unit comprises transmission means comprising at least an inlet unit and an outlet shaft, wherein the inlet unit comprises engagement means designed to reversibly engage the inlet unit on a transmission unit of a motor unit, wherein the outlet shaft is integral with the supporting element and defines the orientation axis, and and wherein the transmission means are configured for transforming an inlet motion of the inlet unit into an outlet rotation of the outlet shaft about the orientation axis, said steering unit comprising a motor unit having a motor and a control unit operatively connected to the motor and to a remote control, the control unit being programmed for operating the motor following a command selected by an operator and orienting the wheel relative to the orientation axis, wherein the inlet unit comprises an inlet shaft mounted in a rotary fashion on the base structure about a respective inlet axis, preferably parallel to the orientation axis and characterised in that the inlet shaft is movable along the respective inlet axis between an engaged position, designed to allow the inlet shaft to engage on the transmission unit of the motor unit, and an idle position, pushing means being preferably active on the inlet shaft to keep it in the engaged position. a base structure designed to be mounted on a conveying device on wheels and a wheel mounted on a supporting element in such a way as to rotate about a relative axis of rotation, wherein the supporting element is mounted on the base structure in such a way as to rotate about an orientation axis positioned transversely to the axis of rotation of the wheel to allow the orientation of the wheel and its axis of rotation about the orientation axis, wherein the steering unit comprises transmission means comprising at least an inlet unit and an outlet shaft, wherein the inlet unit comprises engagement means designed to reversibly engage the inlet unit on a transmission unit of a motor unit, wherein the outlet shaft is integral with the supporting element and defines the orientation axis, and and wherein the transmission means are configured for transforming an inlet motion of the inlet unit into an outlet rotation of the outlet shaft about the orientation axis, said steering unit comprising a motor unit having a motor and a control unit operatively connected to the motor and to a remote control, the control unit being programmed for operating the motor following a command selected by an operator and orienting the wheel relative to the orientation axis, wherein the inlet unit comprises an inlet shaft mounted in a rotary fashion on the base structure about a respective inlet axis, preferably parallel to the orientation axis and characterised in that the inlet shaft is movable along the respective inlet axis between an engaged position, designed to allow the inlet shaft to engage on the transmission unit of the motor unit, and an idle position, pushing means being preferably active on the inlet shaft to keep it in the engaged position.