Patent ID: 7370497

Claim:
A padlock, comprising: a housing; a shackle movably mounted on the housing and having a root section extended into the housing and a free section having a first end extended from the root section and a second end extended outside of the housing; a limit knob movably mounted on the housing to control movement of the free section of the shackle; a movable member movably mounted in the limit knob; and a first locking mechanism mounted in the housing and comprising a key lock unit and a movable shaft mounted on the key lock unit wherein the key lock unit is configured to control movement of the limit knob and has a key hole to receive a matching key; and the movable shaft is driven to move the movable member when the key or an insert is inserted into the key hole of the key lock unit; wherein the limit knob includes a knob body rotatably mounted on the housing and having an outer portion formed with a receiving recess to receive the free section of the shackle and an inner portion formed with a receiving chamber to receive the movable member, and a base portion extended from the knob body into the housing to connect the key lock unit, wherein the receiving recess has a central portion formed with a first opening and a peripheral wall formed with a second opening connected to the first opening.