Flow control device of power steering apparatus

A flow control device of a power steering apparatus comprising:

• a valve receiving bore formed in a housing of a pump and connecting to a supply passage leading operating fluid discharged from said pump;
• a union, arranged in said valve receiving bore, having a union bore connecting to said valve receiving bore;
• a metering orifice arranged in said union bore;
• a flow control valve, arranged in said valve receiving bore, having a spring chamber and a bypass spool for regulating an opening area of a bypass passage in accordance with pressure difference across said metering orifice,
• said spring chamber connected to a downstream side of said metering orifice in said union bore and connected to a reservoir,
• said bypass spool urged by a spring in said spring chamber, said bypass spool having a control rod penetrating said metering orifice for regulating an opening area of said metering orifice in accordance with a movement of said bypass spool;
• and
• a load pressure responsive valve, arranged in said union, for regulating communication between said spring chamber and said reservoir in response to a rise of load pressure of the operating fluid.