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1. (US4279327) Ventilating ladder
Note: Texte fondé sur des processus automatiques de reconnaissance optique de caractères. Seule la version PDF a une valeur juridique
What I claim as my invention is:
1. A folding ladder attachment device to be attached to the top of a roof ladder to aid in cutting ventilation holes in a roof comprising:
a. a pair of side bars separated by a distance greater than the distance across the area through which the ventilation hole is to be cut;
b. a lower bar member transverse to the pair of side bars and integrally secured to the pair of side bars at the ends of the lower bar member;
c. a pair of transverse bar members spaced apart and attached at one end to a center portion of said lower bar member to allow the top portion of the roof ladder to fit tightly between and parallel to the pair of transverse bar members;
d. a pair of sleeves integrally secured to the top portion of the roof ladder through which the pair of transverse bar members slide;
e. a pair of pins that slide through openings in the sleeve portion, openings in the upper portions of the roof ladder, and openings in the pair of transverse bar members to lock the ladder attachment to the roof ladder;
f. and a pair of rigid bar hooks integrally secured to the upper portions of the pair of side bars to secure the ladder attachment device to the ridge of the roof.
2. The ladder attachment device as claimed in claim 1, wherein the lower bar member includes a pair of arms transverse to the side bars, and hinged means at the ends of the arms near the center of the lower bar member so that the arms pivot about the center of the lower bar member.
3. The ladder attachment device as claimed in claim 1, wherein the pair of rigid bar hooks swing between the side bars for storage.
4. The ladder attachment device as claimed in claim 2, wherein the left member and right member of the ladder attachment device fold together by pivoting around the hinge.