The Design Of Detection SystemAbout Locomotive Brake Test-bench Based On LabVIEW

The high efficient and safe railway transportation plays an important role in our highspeed development of national economy. Ensure the safe operation of the rolling stock is thework core of railway departments. The braking system is a series of special device to forcerolling stock slow down or stop, its performance has a direct impact to the safe operation ofvehicles. JZ-7type brake is widely used in each model of diesel locomotive in our country,testing its various performance indicators mainly relys on the JZ-7locomotive brake testbench. The test bench can simulate locomotive brake system, test the performance of theautomatic brake valve, independent brake valve, relay valve, main valve, vice valve,emergency snort valve and operating valve of JZ-7type brake in order to provide scientificdata to determine the quality status of the measured part. The automation degree of JZ-7typelocomotive brake test bench is low. It needs a lot of manual operation and its experimentprocess is complicated. These result in low working efficiency. In the actual situation, workersoften leave out or simplify the test process by themselves. These actions may caused seriousaccidents when vehicle running. A kind of automatic test bench is designed to put an end tothese phenomenons in this paper. The design is based on the original JZ-7locomotive braketest bench.This paper introduces the locomotive brake test bench system which based on virtualinstrument technology in six aspects of from the overview, project design, selection ofdevelopment tools, selection of hardware, software design and system debugging.In theprocess of brake test, it needs to collect real-time wind pressure value and control the airdoors opening and closing. This paper selects data acquisition equipments, wind pressuresensors and solenoid valves to complete the functions, and selects LabVIEW which isregarded as a standard software of data acquisition and instrument control in the world towrite the test procedure.First of all, according to the requirements of the brake test, overall scheme is designedand the running process of software is determined, then development tools are selected.Secondly, according to design requirements, the models of data acquisition devices, sensors,solenoid valves, relays are selected and equipment layout design is made. Next, dependent on“The technology conditions of JZ-7type locomotive air brake test bench”(TB/T2414-93), testprocedure is written by using LabVIEW software. Finally, system debug is made in thelaboratory condition. Debugging results show that the locomotive brake test bench based onLabVIEW can meet the design requirements and achieve the purpose of project development.The design of detection system about locomotive brake test bench based on LabVIEWcan make operation automatic as much as possible. It changes the situation that the tests dependent on manual operation before. It makes the experiment more rigorous, the resultsmore credible, labor intensity lower and work efficiency higher.