System for heating the operators cabin of a machine powered by an internal combustion engine

A system for heating the operator's cabin of a machine powered by an internal combustion engine, comprising a first oil conduit system operating at a predetermined high pressure, the engine including an engine compartment having an enclosed oil pan, said oil conduit system being located wholly within said enclosed oil pan and including a high pressure hydraulic pump for feeding oil under heat and high pressure from the reservoir of oil in said pan and back into said oil reservoir, said oil conduit system further including a throttling element at the discharge side of said pump for heating the oil passing therethrough, and there being provided a closed, second oil conduit system operating at a pressure lower than said predetermined high pressure, said second oil conduit system including a first heat exchanger disposed within said enclosed oil pan in the engine compartment in heat exchange relationship with the oil heated by said first oil conduit system, a second heat exchanger located in the operator's cabin and a circulating pump for circulating oil through said closed oil conduit system, whereby the oil passing through said closed oil system is heated via said first heat exchanger for supplying heat to the operator's cabin via said second heat exchanger, and whereby any leakage of oil from said first oil conduit system operating at said predetermined high pressure, and any leakage of oil from said first heat exchanger, is completely confined within said oil pan to thereby avoid exposure of the engine to danger due to an uncontrolled loss of oil.