Patent ID: 7347129

Claim:
A tool having a torque limiting function comprising: a) a hollow grasping portion having a second slot communicating with a hollow interior of the hollow grasping portion; b) a tubular wrench portion connected to the hollow grasping portion and having: i) four arc portions equally spaced apart and located on a first end thereof, the four arc portions being movable between first and second positions and providing the torque limiting function, the four arc portions having a C-shaped recess located on an exterior periphery thereof; ii) a hollow body portion located between the four arc portions and the hollow grasping portion; and iii) a first slot extending along a length thereof from the first end to a second end of the tubular wrench portion and communicating with a hollow interior of the tubular wrench portion, the first slot communicating with the second slot, opposing ends of the C-shaped recess are spaced apart from the first slot; and c) a C-shaped fastening ring made of a rigid material and inserted into the C-shaped recess, wherein, when the four arc portions are located in the first position, the four arc portions are held in a normal position by the C-shaped fastening ring, and, when the four arc portions are located in the second position, the four arc portions are pressing outwardly against and deforming the C-shaped fastening ring.