Jumping-Mini (Jumping-Board)　

Yoshiyuki Kobayashi 2002/11/20

Plan

A finger suck or a rubber globe (finger portion) can be used as Diaphragm.

Cylinder and Displacer

Paste up a rubber after reducing internal air. It is the same though a finger sack is used. Because, the air expands when a cylinder is heated.

Swing-arm

When a board skids and does not advance,

stick  a vinyl tape or a dress brush on a bottom.