Drainage device

A drainage device including a catheter and a control valve connected with the catheter, characterized in that:

• the control valve has a valve body and a resilient switch, the valve body having a passageway controlled by the resilient switch to be in a normally closed status, a normally open status, or a variable open status adjusted by a pressing force acting on the resilient switch;
• and
• the resilient switch includes an elastic structure, a driving part, a recovery-blocking part and an unlocking handle, wherein the driving part is movable by a deformation response of the elastic structure to have a displacement to alter an opening of the passageway of the valve body;
• the recovery-blocking part is used for providing a recovery-blocking effect on the driving part;
• and the unlocking handle is used for an external force to apply a moment of force on the driving part to release the recovery-blocking effect;
• wherein when the elastic structure is not pressed, the passageway is in a first normal status;
• when the elastic structure is under a press operation, the opening of the passageway is determined according to a relative relationship between the displacement and a displacement threshold, where, when the displacement is not larger than the displacement threshold, the passageway is in the variable open status, and the opening thereof is smaller than the opening of the normally open status, and when the displacement is larger than the displacement threshold, the driving part will be under the recovery-blocking effect provided by the recovery-blocking part to make the passageway situated in a second normal status, wherein when the first normal status is the normally closed status, the second normal status is the normally open status, and when the first normal status is the normally open status, the second normal status is the normally closed status;
• and
• wherein after the passageway is in the second normal status, the unlocking handle can be used to release the recovery-blocking effect of the recovery-blocking part by applying the moment of force, thereby restoring the passageway to the first normal status.