| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve durability of the rubber boot and to prevent the rubber boot from being broken against the rough operation of the joy stick by forming the rubber boot of nitrile rubber with which paraffin-based oil is mixed. SOLUTION: At a nearly center part of a base housing 21, the joy stick 22 as an operation direction input means is provided so that it freely swings in the front/rear, right/left, and oblique directions. Various operation buttons 23, 24, 25, and 26 are arranged on the front side of the upper part of the joy stick 22 and a trigger button 27 is provided on the back side of the upper part of the joy stick 22. On the top surface of the base housing 21, an operation button 28 is provided on the front side. Further, the rubber boot 34 for protection is mounted on the connection part between the joy stick 22 and base housing 21. The rubber boot 34 is formed of nitride rubber. The nitrile rubber is prepared by emulsifying and synthesizing butadiene and acrylonitrile and, specially, has superior oil resistance.</p> |
