FLOW RATE CHARACTERISTIC ADJUSTMENT MECHANISM OF SOLENOID PROPORTIONAL VALVE AND FLOW RATE CHARACTERISTIC ADJUSTMENT METHOD USING THE SAME

摘要

A flow rate characteristic adjustment mechanism of a solenoid proportional valve capable of easily adjusting the flow rate characteristics of the solenoid proportional valve even after a product is assembled and a flow rate characteristic adjustment method using the mechanism. The solenoid proportional valve (1A) comprises a coil bobbin (16) around which a coil (17) is wrapped, a third core (15) fixedly fitted to the coil bobbin (16), a body (2) having an inlet flow passage (3) and an outlet flow passage (4), a valve seat (6) allowing the inlet flow passage (3) to communicate with the outlet flow passage (4), a valve seat (12) opening/closing the valve seat (6), a plunger (10) formed integrally with the valve seat (12), a plate spring (8) energizing the plunger (10) in the direction of the valve seat (6), a first core (9) interposed between the coil bobbin (16) and the body (2), and a bonnet (19) detachably put on the coil bobbin (16). The third core (15), the first core (9), and the bonnet (19) surround the periphery of the coil (17) to form a magnetic circuit. A fixed screw (22) is rotated to move the bonnet (19) in the axial direction so as to change the magnetic circuit.