Wheel-hub gears and casings therefor

A gear casing for a wheel-hub assembly, the gear casing comprising:

• a. a gear housing comprising a drive-gear volume for accommodating therewithin a gearing assembly that is positioned to mediate between a drivetrain member and a wheel-hub member, the drive-gear volume being in fluid communication with opposing first and second openings formed in the gear housing for respective gearing-assembly connections therethrough with the drivetrain member and the wheel hub member;
• b. a lubricant compartment radially displaced from the drive-gear volume and in fluid communication therewith exclusively via an array of one or more lubricant passages disposed circumferentially around a portion of the gear housing, the lubricant-passage array arranged for flow therethrough of a gearing-assembly lubricant between the lubricant compartment and the gear housing;
• and
• c. a plurality of lubricant compartments radially displaced from the drive-gear volume, each lubricant compartment being in fluid communication therewith exclusively via a respective array of one or more lubricant passages disposed circumferentially around a portion of the gear housing, the respective lubricant-passage being arrays arranged for flow therethrough of a gearing-assembly lubricant between the lubricant compartment and the gear housing.

A wheel assembly comprising:

• a. a gear casing comprising:
• i. a gear housing comprising a drive-gear volume for accommodating therewithin a gearing assembly that is positioned to mediate between a drivetrain member and a wheel-hub member, the drive-gear volume being in fluid communication with opposing first and second openings formed in the gear housing for respective gearing-assembly connections therethrough with the drivetrain member and the wheel hub member;
• ii. a lubricant compartment radially displaced from the drive-gear volume and in fluid communication therewith exclusively via an array of one or more lubricant passages disposed circumferentially around a portion of the gear housing, the lubricant-passage array arranged for flow therethrough of a gearing-assembly lubricant between the lubricant compartment and the gear housing;
• b. the gearing assembly positioned to mediate between the drivetrain member and the wheel-hub member, the gearing assembly disposed within in the gear casing and comprising a compound planetary gear train comprising (i) a sun gear in bearinged connection with the drivetrain member of the vehicle so as to be rotated thereby, (ii) a carrier in bearinged connection with the wheel-hub member, and (iii) a plurality of composite planet gears each having multiple radii;
• c. a sub-frame configured to be mounted to a reference frame of a vehicle;
• d. a suspension arm linking the sub-frame to a first connection portion of the gear casing;
• and
• e. a steering system member connected distally to a second connection portion of the gear casing and configured to rotate the wheel-hub member about a steering axis.

A wheel assembly comprising:

• a. a drivetrain member and a wheel-hub member, and a gearing assembly coupled to the wheel-hub member and positioned to mediate between the drivetrain member and the wheel-hub member;
• b. a gear casing comprising:
• i. a gear housing comprising a drive-gear volume for accommodating therewithin the gearing assembly, the drive-gear volume being in fluid communication with opposing first and second openings formed in the gear housing for respective gearing-assembly connections therethrough with the drivetrain member and the wheel hub member;
• ii. a lubricant compartment radially displaced from the drive-gear volume and in fluid communication therewith exclusively via an array of one or more lubricant passages disposed circumferentially around a portion of the gear housing, the lubricant-passage array arranged for flow therethrough of a gearing-assembly lubricant between the lubricant compartment and the gear housing;
• c. the gearing assembly positioned to mediate between the drivetrain member and the wheel-hub member, the gearing assembly disposed within in the gear casing and comprising a compound planetary gear train comprising (i) a sun gear in bearinged connection with the drivetrain member of the vehicle so as to be rotated thereby, (ii) a carrier in bearinged connection with the wheel-hub member, and (iii) a plurality of composite planet gears each having multiple radii;
• d. a brake assembly coupled to the wheel-hub member, the brake assembly being characterized by having a brake caliper connected thereto, wherein a thickness of the gear housing through the drive-gear volume is less than 120% of a width of the brake caliper, the thickness and the width both being in a direction parallel to a central axis of the gearing assembly.