STRUCTURE OF OPERATION ARMS IN PLIERS

PROBLEM TO BE SOLVED: To increase the strength of outer walls by forming the outer walls of operation arms in an S-shape section. SOLUTION: The first grip arm 2 and the second grip arm 3 are supported turnably at the opening and closing center 22. The first operation arm 1 and the second operation arm 4 to open and close both the grip arms 2 and 3 are provided allowable to open and close each other. At the outer wall 6 of the first operation arm 1, the auxiliary structure 8 is added other than its main structure 7, and an S-shape section is formed by the main structure 7 and the auxiliary structure 8. At this main structure 7, a U-shape section is formed by the first side plate 9, the second side plate 10, the first bottom plate 11, and the first opening part 12. And at the auxiliary structure 8, a U-shape section is formed by the second side plate 10 of the main structure 7, the third side plate 13, the second bottom plate 14, and the second opening part 15.