| 摘要 |
<p>Disclosed is a robot arm (50) which is provided with an arm section (2) as a direct acting extensible and retractable joint (J3), said arm section (2) being formed by an upper structure group (20) and a lower structure group (21). The upper structure group (20) and the lower structure group (21) each consist of structures which are connected in series. When the upper structure group (20) and the lower structure group (21) partially engage with each other, there is formed a rectilinearly stiff combined structure consisting of the upper structure group and the lower structure group. When, for example, there is released the pressure contact in the rectilinearly rigid combined structure consisting of the upper structure group and the lower structure group, resulting in the stiffness being relieved, it is possible to make the arm length freely variable. Furthermore, as regards the arm section (2), a surface which particularly has a possibility that fingers or dirt may enter, can be made a flat surface which has no gap at all. Moreover, if a series of upper structures (22) are separated from a series of lower structures (23), both series of structures can be bent by means of rotation shafts (30, 31). When both series of structures are to be housed after being mutually separated, said series of structures can be housed in a robot arm support body (1) in a compact manner. On the basis of the above, it is possible to provide a direct acting extensible and retractable arm mechanism which is compact and wherein it is possible to prevent the catching of fingers and the entry of dirt.</p> |
