| 摘要 |
<p>PURPOSE: A door lock is provided to enable a user to recognize the entering of visitors by ring an alarm when pushing a key pad of a door lock. CONSTITUTION: A door lock comprises an outdoor unit(120), an inner unit(110) and a door-bell button(104). The outdoor unit is installed in the outside of door. A keypad(102) includes a number pad. The inner unit is installed in the door inner side. The door-bell button is installed the predetermined place of the outdoor unit. The door look rings an alarm when a user pushes a key pad of a door lock.</p> |
