| 摘要 |
A swing device of an excavator is provided to reduce the impact and swing noise caused by the swing acceleration of an excavator. A swing device of an excavator includes a swing noise and impact prevention device bypassing hydraulic pressure from a swing motor(4) in the swing acceleration and preventing a rapid drop of swing torque by the excessive rotational inertia of a swing body, and first and second shuttle valves(21,23) operating the swing noise and impact prevention device regardless of the operation direction of a swing joystick, wherein the first shuttle valve is inserted to a flow passage connecting a swing joystick and a swing valve, the second shuttle valve is inserted to a flow passage connecting a swing valve and a swing motor, and the swing noise and impact prevention device is inserted between the first and second shuttle valves and connected with a drain port(Mu) of the swing motor to bypass hydraulic oil. The swing noise and impact prevention device includes a first valve(31) changed over between a neutral position and a second position connected with a first shuttle valve, a second valve(33) changed over between a first position connecting an accumulator and a drain port of a swing motor and a second position of an accumulator and a first valve, a bypass check valve(35) inserted between an accumulator and a second valve, an accumulator(37), and a variable throttle valve(39) changed over between a neutral position and a second position connecting to a second shuttle valve and a drain port of a swing motor. |
