Computer-controlled password lock

Claim 1

A computer-controlled password lock system having a lock drivig circuit and a computer coupled thereto, comprising: keyboard means for entering a keyed-in password; timer means for establishing a time-varying symbol; indicator means coupled to the timer means for indicating the time-varying symbol; memory means for storing a password formed by a plurality of coded symbols; data processing means coupled to the timer means and the memory means for replacing at least one of the coded symbols of the preset password stored in the memory means with the time-varying symbol to form a current password; comparator means coupled to the memory means for detecting coincidence between the keyed-in password and the current password; and means interconnecting the comparator means with the lock driving circuit for generating a lock opening signal in response to said detection of coincidence, said computer further including alarm means coupled to the comparator means for generating an alerting signal in response to non-coincidence between the keyed-in password and the current password, the time varying symbol established by the timer means including at least two variable numerical codes, the plurality of coded symbols of the preset password stored in the memory means including a varying password setting code and a symbol selecting code, said data processing means including means for retrieving the preset password stored in the memory means when said keyed-in password is entered and means for detecting said a varying password setting code and a symbol selecting code to replace at least two different coded symbols of the preset password.