CPC A47H 1/08 (2013.01) [A47H 3/10 (2013.01); A47H 5/0325 (2013.01)] | 6 Claims |
1. An extendable rail, comprising a main rail (1), an auxiliary rail (2) arranged in parallel with the main rail (1); the main rail (1) is shifted in longitudinal direction relative to the auxiliary rail (2) such that the rails are overlappingly positioned, and the main rail (1) has a main first end and a main second end opposite the main first end, the main rail comprising a driving wheel (11) at the main first end and a first reverse wheel (12) at the main second end; the auxiliary rail (2) has an auxiliary first end and an opposite auxiliary second end, the auxiliary first end is outwardly spaced from the main second end and comprises a second reverse wheel (21), and a transition arrangement at the auxiliary second end between the first and second main ends; the transition arrangement (3) comprises a transition casing (31) with a first guiding wheel (32) and a second guiding wheel (33) arranged inside;
a belt loop (4) with a fixed length is wrapped around a portion of the driving wheel (11), the first reverse wheel (12), the first guiding wheel (32), the second reverse wheel (21), the second guiding wheel (33), and another portion of the driving wheel (11) to form the loop.
|