| 摘要 |
A nail designed to be initially driven through a first board, and into a second board so as to assemble the boards with the boards engaging each other, and to be subsequently pulled or removed, as by means of a crowbar or a claw upon a hammer head, so as to disassemble the boards is disclosed as including a head and a shank with a pointed end. A relatively smooth portion of the shank extends axially from the pointed end for a substantial distance. A relatively rough portion, which is formed with annular, frustoconical rings defining annular grooves, extends axially from the relatively smooth portion toward the head for a distance approximately equal to the thickness of the first board. A relatively smooth portion extends axially between the relatively rough portion and the head. The nail has differential holding capabilities per unit length along its shank, when driven the wooden boards. |
