Patent ID: 8066099

Claim:
A retractable ladder, comprising a plurality of ladder sections from top to bottom in which each ladder section comprises a rung member and stiles disposed at both sides of the rung member, wherein the two adjacent ladder sections are slidable relative to each other to achieve extension and retraction of the plurality of ladder sections, characterized in that, the retractable ladder comprising: a plurality of section-positioning lock devices disposed at upper ends of the stiles at both sides of each ladder section except for the uppermost ladder section, each of the section-positioning lock devices comprising: a pin rod laterally disposed in the section-positioning lock device and being movable horizontally, a circular through hole formed on stiles of the respective ladder sections to correspond to the pin rod so that the pin rod can be inserted therethrough to lock the ladder sections, and a first reset spring connected with the pin rod, and the first reset spring applying a biasing force on the pin rod so that the pin rod is inserted into the circular through hole to lock an adjacent stile; and a pedal operated unlock device for releasing the locking of the ladder sections to retract the ladder to a folded state for storage, the pedal operated unlock device comprising: a pedal rotational shaft which is fixed at its two ends to eccentric wheels disposed in inner cavities of the stiles at both sides of the lowest ladder section, an unlock pedal which is fitted over the pedal rotational shaft and is capable of moving side to side along the pedal rotational shaft, an unlock jogger disposed on the eccentric wheel and being movable up and down along the inner cavity of the stile, a nose spike disposed at an upper end of the unlock jogger and an upper portion of enclosure caps of the stiles at both sides of each ladder section except for the uppermost ladder section, and a lateral pin disposed in the middle of the pin rod and being radially perpendicular to the pin rod, wherein a user operates to rotate the unlock pedal and the pedal rotational shaft so that the nose spike moves upwardly and acts on the lateral pin to cause the pin rod to retract, thereby releasing the locking of respective ladder sections with the section-positioning lock devices so as to retract the ladder to the folded state.