US Patent 7980104 Rekeyable lock cylinder

A rekeyable lock cylinder comprises a cylinder body, a plug assembly disposed within the cylinder body and at least one adjusting member. The cylinder body has an inside wall, the plug assembly comprises a plug body having a plurality of pin holes and an opening, a plurality of assembled pins disposed within the pin holes of the plug body and a position block disposed in the plug body. Each of the assembled pins comprises a first rack component having an aligning cavity and a second rack component engaged with the first rack component. The position block has a plurality of pin runners served for disposing the first rack components and a tool-receiving hole corresponding to the opening. The adjusting member is movably disposed within one of the pin holes of the plug body and contacts against at least one first rack component and the inside wall of the cylinder body thereby forming a position difference between the tool-receiving hole and the aligning cavity.