Patent ID: 7306252

Claim:
A pull-type crop harvesting machine for towed movement by a tractor comprising: a frame mounted on ground wheels for movement across ground carrying a standing crop for harvesting; a cutter system mounted across a front of the frame so that the frame carries the cutter system into the standing crop for cutting the standing crop and converging the cut crop into a crop discharge; a hitch arm extending from the frame to a forward end of the hitch arm arranged for attachment to a hitch connector of a tractor by which the frame and the cutter system are towed across the ground; a connecting assembly for connecting the forward end of the hitch arm to a hitch connector of the tractor; a hydraulic circuit for providing drive to the machine comprising: a hydraulic pump for generating a flow of hydraulic fluid under pressure; a hydraulic motor for driving the cutter system; hydraulic connection lines for communicating the flow from the pump to the motor and from the motor back to the pump; and a mechanical drive connection for connecting the pump to a PTO shaft of the tractor; the frame including a transverse frame member extending across the frame at the rear of the hitch arm; the transverse frame member having ground wheels attached thereto for supporting the frame in movement across the ground; the frame including a transverse cutter support bar extending across the frame at the cutting system for supporting the cutting system; at least one of the transverse frame member and the transverse cutter support bar being formed from a tubular structural member which is closed at or adjacent each end so as to form a hollow conduit and having a fluid connection at each end for connection to the hydraulic connection lines such that hydraulic fluid in the hydraulic circuit passes through said at least one of the transverse frame member and the transverse cutter support bar so as to effect cooling of the hydraulic fluid.