×

Keyless entry system

  • US 4,205,325 A
  • Filed: 12/27/1977
  • Issued: 05/27/1980
  • Est. Priority Date: 12/27/1977
  • Status: Expired due to Term
First Claim
Patent Images

1. A keyless entry system for use in an automotive vehicle comprising:

  • means for entering at least one multi-digit code into said system and generating representative electrical signals;

    means for permanently storing a predetermined code representing n sequential digits, where n is a predetermined number;

    first means for addressing said permanent storing means in response to each individually entered digit;

    means for storing a user programmed code representing n sequential digits;

    second means for addressing said user code storing means in response to each individually entered digit;

    means for sequentially comparing each individually digit entered into said system with the read out contents of said permanent storing means and with the read out contents of said user code storing means, wherein said comparing means is connected to respective first and second addressing means to advance a corresponding addressing means to its next address whenever a comparison indicates equality and to reset a corresponding addressing means to its initial address whenever a comparison indicates inequality;

    said first and second addressing means respectively generate corresponding first and second enabling signals when sequentially advanced to an n+1th address; and

    means for unlocking a door of said vehicle in response to either of said first and second enabling signals.

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