| 摘要 |
An improved locknut has a hexoganal body with a threaded central opening. The threaded central opening has noncircular lock thread convolutions with a reduced pich. Standard thread convolutions are disposed adjacent to the bottom of the opening to facilitate engagement with the mating thread. To form the lock thread convolutions, a hexagonal nut is moved through a nip between a pair of rotating externally toothed indenting wheels. As the nut passes through this nip, crest portions of the teeth on the indenting wheels move into engagement with opposite flat side surfaces of the nut body. As the nut body continues to move through the nip, the externally toothed wheels indent the nut body at spaced-apart locations. To promote accurate control of the axial extent of the lock thread convolutions, the external teeth on the indenting wheels have a tooth depth which is greater than the depth of the indentations formed in the opposite sides of the nut. This prevents deformation of the nut body by the root portions of the indenting teeth. The indenting teeth extend at an acute angle to the axis of rotation of the wheels to form the indentations with sloping inner surfaces.
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