Compressor having speed and intake regulation valve control

• Main Author: TOTSUKA JUNICHIRO
• Format: Patent
• Language: English
• Published: 29.07.2003
• Edition: 7
• Subjects: BLASTING; HEATING; LIGHTING; MECHANICAL ENGINEERING; POSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENTMACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENTPUMPS; WEAPONS

A compressor that enables the increase of compression efficiency, the prevention of abnormal temperature rising in the discharge, and the reduction of power loss, includes a compressor body 11, an intake registration valve 12 in the inlet side, and a pressure sensor 18 provided in the discharge side to be able to detect pressure. A control section 22 outputs a control signal for controlling the rotational speed of a motor 21 for driving the compressor body 11 based on a pressure signal indicating a detected pressure from the pressure sensor 18, when the rotational speed is higher than a predetermined value, the intake regulation valve 12 is opened and a control signal for negating a deviation of the detected pressure to the predetermined target pressure is outputted from the control section 22, thereby controlling the rotational speed, and when the rotational speed is reached to the predetermined value, the control is switched to the open/close control for opening/closing the intake regulation valve 12 in response to a pressure fluctuation in the discharge side in place of the rotational speed control, thereby controlling pressure fluctuation in the discharge side. Here, the predetermined value is set to such a value that the leakage quantity of gas, compressed by the screw compressor, into the inlet side of the screw compressor will not be increased as rotational speed of the motor is decreased.