|국가/구분||United States(US) Patent 등록|
|미국특허분류(USC)||182/129; 182/127; 280/079.7; 280/047.3; 016/029|
|발명자 / 주소|
|출원인 / 주소|
|대리인 / 주소||
|인용정보||피인용 횟수 : 2 인용 특허 : 15|
Embodiments of ladders (22, 106) are disclosed which utilize a wheel (112) to allow users to transport these ladders easily by rolling along a surface without carrying the entire weight of the ladder. The wheel (112) are located in positions which do not interfere with the use of these ladders.
What is claimed is: 1. A ladder comprises: a pair of rails, each of the pair of rails including an end surface; and a plurality of wheels adjustably clamped to the rails; the plurality of wheels for allowing a user to transport the ladder by lifting only a portion of weight of the ladder, the plurality of wheels are in contact with a ground surface when the end surface of the rails is above the ground surface when the ladder is transported and the plurality of wheels are above the ground surface when the end surface of the rails are in contact with the ...