Patent ID: 7163077

Claim:
A frame structure of a vehicle comprising a flywheel housing, an intermediate housing and a transmission case that are connected to each other along a longitudinal axis of the vehicle to constitute a vehicle frame with an inner space for accommodating a running-power transmission path for transmitting power from an engine to drive wheels via a HST unit: wherein said flywheel housing has a first abutting surface and a second abutting surface respectively located closer to a first end and a second end of said flywheel housing along the longitudinal axis of the vehicle, said first abutting surface being connected to the engine, said second abutting surface being connected to said intermediate housing and having a first opening through which said HST unit can pass, said flywheel housing has a hollow shape with a center axis substantially coaxial with a crank shaft of said engine; said intermediate housing has a hollow body portion and a flange portion, said hollow body portion having a first end and a second end and extending along the longitudinal axis of the vehicle with a center axis displaced downward from said crank shaft, and said flange portion being located closer to said first end of said hollow body portion in a state of having a lower end substantially at the same level as that of the hollow body portion and an upper end higher than that of the hollow body portion, and having an opening in a radial center thereof, said opening of the flange portion serving as a first-end opening of said intermediate housing along the longitudinal axis of the vehicle; said flange portion has an upper extension extending outwards in a radial direction from a top wall of the hollow body portion, a lateral extension extending outwards and inwards in a radial direction from a lateral wall of the hollow body portion and a lower extension extending inwards in a radial direction from a bottom wall of the hollow body portion, so as to define an abutting surface located opposite to said second abutting surface of said flywheel housing, a support surface located radially inward of said abutting surface so as to support said HST unit, and said first-end opening located radially inward of said support surface.