Oil supply apparatus of a four-stroke-cycle engine

An oil supply apparatus of a four-stroke-cycle engine, comprising:

• an oil chamber for holding oil;
• an oil supply passage connecting said oil chamber with an inside of said engine, wherein an inside pressure of said engine fluctuates according to movement of a piston, said oil supply passage supplies oil from said oil chamber to said inside of said engine according to pressure fluctuations inside of said engine;
• an oil return passage for connecting said oil chamber with the inside of said engine, said oil return passage returns oil from inside of said engine to said oil chamber according to pressure fluctuations inside of said engine;
• an air inhalation vent provided in said oil supply passage and disposed at a center of said oil chamber;
• a return vent provided in said return passage and disposed at said center of said oil chamber;
• a restrictor formed in said oil supply passage for restricting air flow from said air inhalation vent;
• and
• an oil inhalation passage providing at one end an oil inlet disposed at a bottom of said oil chamber and at another end an oil outlet at a portion facing said restrictor.

An oil supply apparatus of a four-stroke-cycle engine, comprising:

• an oil chamber for holding oil;
• an oil inlet passage including an oil inlet pipe rotatably supported in said oil chamber, and an elastic pipe formed by elastic materials and connected with said oil inlet pipe, said elastic pipe having an oil inlet at one end soaked in oil held in said oil chamber;
• a weight attached to said oil inlet passage adjacent to said oil inlet;
• an oil supply means connected with said oil inlet pipe for supplying oil to inner parts of the engine from said oil chamber via said oil inlet;
• an oil return passage for connecting an inside of said engine with an outer periphery of said oil supply pipe disposed in said oil chamber, wherein said oil return passage returns oil from said inside of said engine to said oil chamber according to pressure fluctuations inside of said engine due to reciprocation of a piston;
• and
• a flange attached to said oil supply pipe at a portion facing towards an end of said oil return passage in said oil chamber.

An oil supply apparatus of a four-stroke-cycle engine, comprising:

• a chamber for holding oil;
• an inlet passage including an oil inlet pipe rotatably supported in the chamber, said oil inlet pipe having an inlet at one end soaked in oil held in the chamber;
• an oil supply pipe for supplying oil to an inside of the engine from the chamber via the oil inlet pipe;
• a return passage, connected between an outer periphery of the oil supply pipe and the inside of the engine, for returning oil from the inside of the engine to the chamber according to oil pressure fluctuations inside of the engine due to reciprocation of a piston;
• and
• a flange attached to the oil supply pipe at a portion facing towards an end of the return passage in the chamber;
• whereby the inside of the engine is lubricated even when the engine is tilted in any direction.