Material supply system

A material supply system comprising:

• a supply device for sucking material from a storage tank or another reservoir, the supply device having an outlet port through which the sucked material is supplied under high pressure;
• a primary supply line connected at an inlet thereof with the outlet port of the supply device for supplying the sucked material under a first pressure through the primary supply line;
• a secondary supply line for supplying the sucked material under a second pressure;
• a pressure reducing valve connected between an outlet of the primary supply and an inlet of the secondary supply line for making the second pressure lower than the first pressure;
• a discharger for quantitative supply of material to a work, the discharger having an inlet port connected with the outlet of the secondary supply line;
• a pressure sensor for sensing an port pressure nearly at the inlet port of the discharger and outputting a pressure signal as the basis for controlling the second pressure;
• wherein, on the basis of the pressure signal, the pressure reduction ratio of a pressure reducing valve is so controlled that, if the sensed pressure is higher than a set upper limit value, the valve is fully closed, and that, if the sensed pressure is lower than a set lower limit value, the opening of the valve is adjusted to a value at which a slightly larger amount of material can flow through the valve than the total amount of material flowing therethrough while the discharger is operating;
• and
• an accumulator provided on the secondary supply line;
• wherein an internal pressure of the accumulator rises when the accumulator is filled with the material, and wherein the accumulator restrains the port pressure from exceeding the upper limit value and from falling below the lower limit value.