Digital entrance opening and closing device

A digital opening and closing device for an entrance, comprising:

• a housing comprising an outer casing installed on an outdoor surface of a door, and an inner casing coupled to the outer casing with the door interposed between the inner and outer casings;
• a password input unit provided on the outer casing of the housing, the password input unit being used in inputting a password;
• a door opening and closing unit installed in the housing, the door opening and closing unit conducting an operation of opening or closing the door in response to a control signal of a control unit;
• the control unit comparing a password input to the password input unit with a preset reference password and controlling the door opening and closing operation of the door opening and closing unit;
• an opening button provided on the inner casing of the housing, the opening button being connected to the control unit and used in automatically opening the door;
• a manual opening button applying a signal to the control unit to prevent the door from being automatically locked when the door is closed;
• and
• a power supply supplying drive power to the elements,
• wherein the door opening and closing unit is configured such that:
• a door is opened by an operation of pushing or pulling a door handle in a direction in which the door opens;
• when the door handle is pushed or pulled, opening of the door is sensed by a reduction, due to rolling motion of a roller separately installed in the door opening and closing unit, in speed at which the door handle is pushed or pulled;
• and locking of the door can be selectively controlled in such a way that the door is automatically locked when the door is closed, or the door is prevented from being automatically locked when the door is closed.