Rotary electrohydraulic actuator

A rotary electrohydraulic actuator comprising:

• a hydraulic motor including a hydraulic motor housing having a first fluid inlet, a second fluid inlet, a first fluid outlet and a second fluid outlet, and a hollow rotor disposed in the hydraulic motor housing so as to rotate about a rotational axis, the rotor including a through opening that is centered on the rotational axis, whereby the rotor provides a gear-free connection to a driven shaft when the driven shaft is disposed in the through opening;
• a first manifold portion that is spaced apart from the rotational axis and defines a first portion of a fluid path through the rotary electrohydraulic actuator, the first portion of the fluid path extending between the first fluid inlet and the first fluid outlet, and a second manifold portion that is spaced apart from the rotational axis and defines a second portion of the fluid path, the second portion of the fluid path extending between the second fluid inlet and the second fluid outlet, the first manifold portion connected to the hydraulic motor housing in such a way as to permit the first portion of the fluid path to communicate with the first fluid inlet and the first fluid outlet and the second manifold portion connected to the hydraulic motor housing in such a way as to permit the second portion of the fluid path to communicate with the second fluid inlet and the second fluid outlet;
• a hydraulic pump disposed in the fluid path;
• and
• an electric motor that is configured to drive the hydraulic pump,
• wherein
• the first manifold portion is disposed on a first side of the hydraulic motor, the second manifold portion is disposed on a second side of the hydraulic motor, the first manifold portion is connected to the first fluid inlet of the hydraulic motor on the first side, the second manifold portion is connected to the second fluid inlet of the hydraulic motor on the second side, and the second side is opposed to the first side, and
• operation of the electric motor causes the hydraulic pump to supply pressurized fluid to one of the fluid inlet and fluid outlet of the hydraulic motor.

A rotary electrohydraulic actuator comprising a hydraulic motor including a hydraulic motor housing having a fluid inlet and a fluid outlet, and a hollow rotor disposed in the hydraulic motor housing so as to rotate about a rotational axis, the rotor including a through opening that is centered on the rotational axis, whereby the rotor provides a gear-free connection to a driven shaft when the driven shaft is disposed in the through opening,

• a manifold that defines a portion of a fluid path through the rotary electrohydraulic actuator, the portion extending between the fluid inlet and the fluid outlet, the manifold connected to the hydraulic motor housing in such a way as to permit the fluid path to communicate with the fluid inlet and the fluid outlet and the manifold to be spaced apart from the rotational axis;
• and
• a power plant mounted on the hydraulic motor via the manifold, the power plant including:
• a first hydraulic pump disposed in the fluid path;
• a second hydraulic pump disposed in the fluid path;
• and
• an electric motor that includes a rotor having a rotor first end and rotor second end that is opposed to the rotor first end,
• wherein
• the first hydraulic pump is connected to the rotor first end so as to be driven by the electric motor,
• the second hydraulic pump is connected to the rotor second end so as to be driven by a the electric motor, and
• operation of the electric motor causes the first hydraulic pump and the second hydraulic pump to supply pressurized fluid to one of the fluid inlet and fluid outlet of the hydraulic motor.