DESIGN, OPERATION, AND UTILIZATION OF CHANGEABLE-MESSAGE SIGNS WITH EMPHASIS ON THE ROTATING-DRUM TYPE

ALTHOUGH TABLES ARE PRESENTED ON THE FUNCTIONS AND TYPES OF VARIABLE MESSAGE SIGNS AVAILABLE, THE ROTARY DRUM TYPE IS SINGLED OUT FOR SPECIAL ATTENTION. BASICALLY, IT IS DESCRIBED AS A TRIANGULAR-SHAPED DRUM PIVOTED ON EACH END, MOUNTED WITHIN AN ENCLOSURE WITH ROTORS ATTACHED TO EACH FACE BEARING THE MESSAGE SIGN. HEATING COILS LOCATED IN THE PERIPHERY OF THE DRUM OPENING PREVENT ICE FORMATION: A 12-V DC MOTOR IS PROVIDED IN THE EVENT OF POWER FAILURE: MANUAL ROTATION OF THE ROTORS IS A BUILT-IN FEATURE. SIMPLE RELAYS, TIMERS, THERMOSTATS, CAPACITOR MOTORS, AND MICROSWITCHES ARE COMBINED IN A STRAIGHT-LINE HARDWIRE CIRCUITRY. TWO TYPES OF REMOTE CONTROL SYSTEMS ARE DESCRIBED: (1) AN UNDERGROUND HARD-WIRE CABLING SYSTEM FOR CONTROL UP TO 5 MILES, AND (2) A TIME-SHARING OF A 2-WIRE COMMUNICATION CIRCUIT FOR SIGNS OVER LONG DISTANCES.

Media Info

  • Media Type: Print
  • Features: Tables;
  • Pagination: p. 33-36
  • Monograph Title: THE CHANGEABLE-MESSAGE CONCEPT OF TRAFFIC CONTROL
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00226393
  • Record Type: Publication
  • ISBN: 0309020530
  • Files: TRIS, TRB, ATRI
  • Created Date: Feb 3 1973 12:00AM