主权项 |
1. In a clevis type hook, including a hook body with a tip end, a shank end including a clevis having a first upper arm and a second, spaced lower arm, said arms each a through passage, said passage having a common through passage axis, said tip end and the upper arm of said shank end spaced to define an elongate, receiving slot with an open side, the improvement comprising:
a twist lock latch member mechanism for substantially closing the open side of the receiving slot, said latch member mechanism including an elongate shaft affixed to and projecting from said latch member, said shaft member having a top end and a bottom section, said bottom section axially slidably fitted through said clevis passages and rotatable about the axis; said latch member further including: a body closure member with an elongate closure surface sized for placement to substantially close the elongate receiving slot, said closure surface radially spaced from the slide axis and pivotally moveable about said axis between a position closing said receiving slot and a position opening said receiving slot, said body closure member configured along a lower edge to fit over a surface of said upper arm of said shank, said shank end and said lower edge comprising a detent and boss engagement couple; and a biasing element intermediate the lower arm and a spring retention element on the shaft to bias the shaft and closure member axially to maintain the closure surface in said slot closing position. |