Patent ID: 8372029

Claim:
A fluid feeder which feeds a fluid into a balloon made of an elastic material so as to inflate, the fluid feeder comprising: a cylinder that is formed in a cylindrical shape provided with a first end of a distal end side and a second end of a proximal end side and contains the fluid, a plunger that is inserted into the cylinder via the second end in a freely advancing and retracting manner in an axial direction, in order to push out the fluid contained in the cylinder from the first end to the outside of the cylinder, a plurality of engaging members to regulate the moving distance of the plunger so as to set a predetermined distance, and an engaged portion provided on the cylinder, which fixes the plunger to a position that corresponds to the predetermined distance regulated by engaging with the engaging members, wherein the plurality of engaging members comprises: a first engaging member disposed along a moving direction of the plunger; a second engaging member located closest to a proximal side of the plunger than the first engaging member, member and the second engaging member disposed in a linear arrangement, wherein the second engaging member is the next closest to the first engaging member in the proximal direction; and a third engaging member located closer to a proximal side of the plunger than the second engaging member, the first engaging member, second engaging member and third engaging member disposed in a linear arrangement, wherein the third engaging member is the next closest to the second engaging member in the proximal direction, and, wherein a distance between the second engaging member and the third engaging member is longer than a distance between the first engaging member and the second engaging member so that the moving distance of the plunger is capable of varying with respect to a movement of the plunger.