1.Application background

The portable pantograph detector is utilized for the inspection and repair of the rolling stock Instead of the traditional wire rope tensile test method, it employs distance measurement method featuring built-in force bar pull wire, which helps avoid the complicated operation of the pulling and drawing wire during the test, and it reduces the instrument sizing and weight, at the same time, additional test items are made with improved detection accuracy and efficiency.

2、System principle

1) After confirmation with the operator in the cab that the air pressure of the railway car is above 900Kpa and the pantograph no need for measuring has been excluded. Notify the operator of lifting the pantographs to be tested;

2) During the bowing process, hook the instrument in the middle of the bow head, pull the instrument handle downward, stare at the laser beam with great care and make sure the laser beam stays at the bow beam of the bow. In the process of this pull down operation, if the bow pull down speed is higher than the specified speed, the buzzer built in the instrument will give off alarm/beeping at a quick rate; on the contrary, if the bow pull down speed is lower than the preset speed, the buzzer built in the instrument will give off alarm/beeping at a slow rate. If this pull down speed is within the range of the designated values, the buzzer built in the instrument won’t give off alarm/beeping;

Figure 1, instrument hook in the middle of the bow the head area     Figure 2, uniform drop-down instrument

3) After the pantograph is pulled down within the specified distance, slowly release the pull-down force on the instrument to have the pantograph move upward at the same constant speed; in the release-up process, if the speed is higher than the specified speed, the instrument is built in will give off alarm quickly. if the speed is lower than the designated speed, the buzzer will give off alarm slowly. if the speed is within the specific range preset, the buzzer won’t give off alarm.

4) When the moving speed is within the range of the specified upward speed and the downward speed, the instrument automatically records the pulling force and the bow height. If the speed does not meet the requirements, data will not be recorded;

5) After the bow height exceeds the preset range, use the other hand to hold the bow, while the hand held onto the pantograph gets off it and the data will be uploaded to the handheld terminal;