| 摘要 |
A retractable step stool includes an enclosure, a lower step and an upper step. The steps are slidably attached to opposing side interior walls of the enclosure; each step has a front surface and a tread surface adjacent to a top edge thereof. A mechanism at the rear of the lower step includes an extension spring secured the enclosure and levers connected to the extension spring. The spring is under tension while the step stool is closed, and when released causes both the lower and upper steps to move outward from the enclosure. In the closed position, the upper and lower steps are housed inside the enclosure while the upper step front surface and lower step front surface are flush with each other; in the open position, the steps extend outward from the enclosure, the lower step extending further from the upper step so that the tread surfaces are exposed. |
