Damping is generated when viscous oil passes through the throttle hole. The smaller the throttle hole, the greater the damping force. The greater the oil viscosity, the greater the damping force
If the size of the orifice remains the same, when the pneumatic butterfly valve operates at a high speed, excessive damping will affect the absorption of impact
Therefore, a disc shaped leaf spring valve is set at the outlet of the orifice. When the pressure increases, the valve is jacked open, the orifice opening increases, and the damping decreases