VARIABLE INTAKE DEVICE INCLUDING HINGE, CYLINDER, BELLOWS, HYDRAULIC PRESSURE SUPPLY SOURCE, SOLENOID VALVE, ELECTRONIC CONTROL UNIT, AND RETURN SPRING

摘要

PURPOSE: A variable intake device is provided to install a cylinder and a bellows for varying the length of an intake passage to the rear of a runner connected to an intake port, to vary the length of the intake passage for inflow of intake air according to an operation area of an engine. CONSTITUTION: A variable intake device comprises a hinge(23) connecting one side of a surge tank(21) and an engine body to enable runners(22) to turn with one side of the surge tank as a starting point; cylinders(30) having one end connected to an intake port(40) and the other end having pistons(32) connected to the rear ends of the runners; a bellows(36) having one end fixed to the outer periphery of the cylinder and the other end fixed to the ends of the runners to prevent intake air from escaping to the outside; a hydraulic pressure supply source(50) to which a hydraulic line(52) is connected to make hydraulic pressure flow into the cylinder; a solenoid valve(54) formed in the middle of the hydraulic line to control inflow and outflow of the hydraulic pressure; an ECU(Electronic Control Unit,56) controlling the operation of the solenoid valve according to an operation area of an engine; and return springs(34) pulling one end of the piston to make the runners return to the original position when hydraulic pressure comes off by providing force of a direction opposite to the operating direction of the cylinder.