×

Building security system

  • US 4,937,855 A
  • Filed: 02/09/1988
  • Issued: 06/26/1990
  • Est. Priority Date: 02/09/1988
  • Status: Expired due to Fees
First Claim
Patent Images

1. A building security system for coupling to a building telephone line which includes a building subscriber telephone line connected to a subscriber telephone set at one end and a central office line at the other end, the central office line leading to a central office exchange, and a visitor entrance panel proximate a building entrance door, comprising:

  • a microprocessor means for controlling operation of said system, for receiving and transmitting data and control signals to and from said central office exchange, said entrance panel and said subscriber telephone set and thereby controlling communication between a central office caller, a subscriber and a visitor via said building telephone line;

    programmable memory means for storing preselected security codes and an operating program for operation of said microprocessor means;

    a building door lock means coupled to said entrance door;

    means for selectively coupling said microprocessor means directly to a reserved central office line leading from said building to the central office exchange, wherein said coupling means responds to control signals from the entrance panel or to signals received via said reserved line; and

    wherein said microprocessor means includes means for distinguishing between a visitor call and a security entry code sequence and for comparing a security entry code sequence being entered with stored security entry codes in said memory means and for unlocking the entrance door on recording a correspondence between an entered security code sequence and a stored security code and wherein said microprocessor means further includes means responsive to control signals received from a subscriber telephone set to send a control signal to said building entrance door lock means to cause the unlocking of said door.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×