| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable a patient to stably sit on a seat with the step seat length equivalent to the foot length of a patient adapting to the individual difference by the old and young, male and female, and so on by constituting the step position against the step seat of a chair for dental treatment changeably and adjustably in longitudinal direction of the step seat. SOLUTION: An arcuate back arm 12 directly connected with a back rest 13 of a chair 50 for dental treatment is interlockingly connected with a step seat 5 by a step link 7. In the step seat 5, the lower ends of cylinder shafts 3b, 6b are pivotally mounted at both ends left and right to the lower back of a step movable board 1a on which a step 1 is fixed by a step upper pivotable shaft 1b and a step lower pivotable shaft 1c. Piston rods 3a, 6a on the upper part of each cylinder shaft 3b, 6b are fitted to hydraulic cylinders 4, 6. The upper ends of hydraulic cylinders 4, 6 are supported by bearings 8, 8a fixed on a seat frame 10, and the movable board 1a is extended and shrunk by the operation of both cylinders 4, 6.</p> |
