Combined motor and brake with rotating brake-release piston

A combined hydraulic motor and brake comprising:

• a stationary housing defining a shaft passage for receiving a drive shaft;
• a rotatable housing mounted at least partially over the stationary housing;
• a hydraulic motor for rotating the drive shaft relative to the stationary housing;
• a coupler for coupling the drive shaft to the rotatable housing;
• and
• a brake piston mounted between the rotatable housing and the coupler and frictionally engaged with the rotatable housing and the coupler such that the coupler, the rotatable housing and the brake piston are configured to rotate as a unit when driven by the drive shaft, the brake piston further including two or more sealing arrangements that remain substantially static as the brake piston rotates with the rotatable housing and the coupler;
• wherein the brake piston is configured to actuate a brake assembly having first brake pads mounted to the stationary housing and second brake pads carried by the rotatable housing such that the second brake pads rotate relative to the first brake pads when the rotatable housing rotates relative to the stationary housing, the first and second brake pads being interleaved relative to one another.

A combined hydraulic motor and brake comprising:

• a stationary housing defining a shaft passage for receiving a drive shaft;
• a rotatable housing mounted at least partially over the stationary housing;
• a hydraulic motor for rotating the drive shaft relative to the stationary housing;
• a coupler coupled to the rotatable housing;
• a piston mounted between the rotatable housing and the coupler such that the coupler, the rotatable housing and the piston are configured to rotate as a unit when driven by the drive shaft, the piston further including two or more sealing arrangements that remain substantially static as the piston rotates with the rotatable housing and the coupler;
• and
• a spring-actuated brake including a brake pack having first brake pads mounted to the stationary housing and second brake pads carried by the rotatable housing such that the second brake pads rotate relative to the first brake pads when the rotatable housing rotates relative to the stationary housing, the first and second brake pads being interleaved relative to one another, the spring-actuated brake being configured to engage by receiving a spring-applied braking force directed through the piston to the brake pack to compress the first and second brake pads together such that relative rotation between the rotatable and stationary housings is resisted by friction between the first and second brake pads, and wherein the brake is released by applying hydraulic pressure to the piston to generate a brake release force that opposes the braking force.

A combined hydraulic motor and brake comprising:

• a hydraulic motor including a hydraulic motor housing;
• a drive shaft assembly that is driven by the hydraulic motor;
• a stationary housing fixed relative to the hydraulic motor housing;
• a rotatable housing that is rotatably driven about an axis of rotation by the drive shaft assembly;
• a brake for resisting relative rotation between the rotatable housing and the stationary housing;
• a piston that is hydraulically actuated to release the brake, the piston being carried with the rotatable housing such that the piston, the rotatable housing and at least a portion of the drive shaft assembly are configured to rotate as a unit about the axis of rotation;
• wherein an outer diameter of the piston is sealed against the rotatable housing and an inner diameter of the piston is sealed against the portion of the drive shaft assembly.

A combined hydraulic motor and brake comprising:

• a stationary housing defining a shaft passage for receiving a drive shaft;
• a rotatable housing mounted at least partially over the stationary housing;
• a hydraulic motor for rotating the drive shaft relative to the stationary housing;
• a coupler for coupling the drive shaft to the rotatable housing;
• and
• a brake piston mounted between the rotatable housing and the coupler and frictionally engaged with the rotatable housing and the coupler such that the coupler, the rotatable housing and the brake piston are configured to rotate as a unit when driven by the drive shaft, the brake piston further including two or more sealing arrangements that remain substantially static as the brake piston rotates with the rotatable housing and the coupler;
• wherein the coupler is coupled to the rotatable housing by a plurality of fasteners that are circumferentially spaced around a perimeter of the coupler.

A combined hydraulic motor and brake comprising:

• a stationary housing defining a shaft passage for receiving a drive shaft;
• a rotatable housing mounted at least partially over the stationary housing;
• a hydraulic motor for rotating the drive shaft relative to the stationary housing;
• a coupler for coupling the drive shaft to the rotatable housing;
• a brake piston mounted between the rotatable housing and the coupler and frictionally engaged with the rotatable housing and the coupler such that the coupler, the rotatable housing and the brake piston are configured to rotate as a unit when driven by the drive shaft, the brake piston further including two or more sealing arrangements that remain substantially static as the brake piston rotates with the rotatable housing and the coupler;
• and
• a bearing positioned between the stationary housing and rotatable housing for allowing the coupler, the rotatable housing, and the brake piston to rotate relative to the stationary housing.

A combined hydraulic motor and brake comprising:

• a stationary housing defining a shaft passage for receiving a drive shaft;
• a rotatable housing mounted at least partially over the stationary housing;
• a hydraulic motor for rotating the drive shaft relative to the stationary housing;
• a coupler for coupling the drive shaft to the rotatable housing;
• and
• a brake piston mounted between the rotatable housing and the coupler and frictionally engaged with the rotatable housing and the coupler such that the coupler, the rotatable housing and the brake piston are configured to rotate as a unit when driven by the drive shaft, the brake piston further including two or more sealing arrangements that remain substantially static as the brake piston rotates with the rotatable housing and the coupler;
• wherein the two or more sealing arrangements comprise at least one outer radial piston seal positioned between the brake piston and the rotatable housing and at least one inner radial piston seal positioned between the brake piston and the coupler.