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|국가/구분||United States(US) Patent 등록|
|발명자 / 주소|
|출원인 / 주소|
|대리인 / 주소||
|인용정보||피인용 횟수 : 0 인용 특허 : 95|
Embodiments of the invention are directed to a protective collar that covers the edges of a manhole or other personnel entryway. One device comprises at least two pieces and a hinge that connects the two pieces, which allows the device to be folded for storage. Another device includes a skirt portion that extends further into the manhole. A further device includes at least one light to provide light into the manhole. A still further device includes a surface port that provides a connecting point for a line, and a subsurface port that provides a connectin...
1. A device comprising: a first portion that has a diameter that is larger than that of a manhole and covers a surface that is adjacent to the manhole;a second portion that has a diameter that is smaller than that of the manhole and extends into the opening of the manhole;a third portion that connects the first portion and the second portion; andan opening that is formed by the first portion, the second portion, and the third portion;wherein in operation, the device is removably placed about a manhole with the first portion extending around the manhole, ...