Patent ID: 6241038
Filing Date: 2001-06-05
Classification: F16H,Y10T

Abstract:
A tractor comprising:an engine mounted on a wheeled frame to provide operative power;a power transmission mechanism operatively associated with said engine to transfer operational power from said engine to different parts of said tractor, said power transmission mechanism including a drop box including a gear set requiring lubrication;a hydraulic circuit having a source of lubrication fluid under pressure, said hydraulic circuit including an oil cooler and an outlet line therefrom carrying lubrication fluid under pressure; anda hydraulic lube circuit providing lubrication fluid to said gear set in said drop box, said hydraulic lube circuit including:a first line connected to said oil cooler outlet line to draw only a portion of the lubrication fluid flowing therethrough and direct said lubrication fluid into said drop box;a hydraulic motor in communication with said first line to be driven by the lubrication fluid drawn through said first line before reaching said drop box;a hydraulic pump driven by said hydraulic motor to pump said lubrication fluid from said drop box, said hydraulic motor and said hydraulic pump mounted on a common shaft, said hydraulic pump having a larger displacement than said hydraulic motor so that said hydraulic pump draws more lubrication fluid from said drop box than said hydraulic motor will pass into said drop box; andmeans including a stand pipe connected to said hydraulic pump to maintain a constant supply of lubrication fluid within said drop box.