ANTENNA CABLE DISCONNECTION DETECTING DEVICE FOR RADIO COMMUNICATION DEVICE FOR CONSTRUCTION MACHINE, AND RADIO COMMUNICATION DEVICE FOR CONSTRUCTION MACHINE

摘要

The present invention provides an antenna cable break detector that is used with a construction machine wireless communication apparatus to properly detect a break in an antenna cable. The present invention also provides a construction machine wireless communication apparatus that is equipped with the above antenna cable break detector. The antenna cable 4 includes a central wire 6 and an armor wire 7 that is positioned concentrically outside the central wire. One end each of the central wire 6 and the armor wire 7 is connected to a communication device 2. The other end of the central wire 6 is connected to an antenna 3. The other end of the armor wire 7 is grounded. The antenna cable break detector comprises direct current shutoff means 10a that is connected to the armor wire 7 of the antenna cable 4 to shut off the flow of a direct current 15 from the armor wire 7 to the communication device 2, and current shutoff detection means 10c that is connected to the armor wire 7 of the antenna cable 4 to detect the shutoff of the flow of a direct current 15 to the armor wire 7.