Air spring type suspension

An air spring type suspension, comprising:

• a cylinder including an air chamber;
• an outer tube surrounding the cylinder and constituting a buffer chamber connected to the air chamber outside the cylinder;
• a damper capable of being inputted into and outputted from the air chamber;
• a piston rod disposed in the air chamber and inserted into the damper;
• a plunger movable in the buffer chamber and dividing an inner space of the buffer chamber to define an effective pressure space connected to the air chamber, a volume of the effective pressure space changed according to a movement of the plunger;
• and
• a driving means for moving the plunger,
• wherein a single closed space is constituted by the air chamber and the erective pressure space, and
• wherein a pressure change of the air chamber is induced by a movement of the plunger.