Study On Shift Performance Of Manual Cycle Shift Mechanism For Flameproof Diesel Engine Locomotive

Flameproof diesel engine locomotive is widely used in rail transport of coal mine,with great traction, strong overload capability, high efficiency and flexibility. The shift operation of flameproof diesel engine locomotive is complex and difficult. In addition, the poor working condition underground and long time tense work easily make driver fatigue, results in misoperation or even accidents. Manual cycle shift mechanism replaces the ordinary manual shift mechanism, in order to make the shift operation easier and reduce the work intensity.The manual cycle shift mechanism, improved from ordinary manual shift mechanism, requires only upshift and downshift two operations, simplifies the shift operations and reduce work intensity of driver. It has a positive role to promote the flameproof diesel engine locomotive. The shifting performance of manual cycle shift mechanism was analyzed in this paper, based on virtual prototyping technology. It has reference value to the design and application of manual cycle shift mechanism.Firstly, the structure and working principle of manual cycle shift mechanism and the synchronization process were introduced. And the shift performance evaluation method of cars was discussed. Secondly, the key parameters and calculation methods were found out, through theoretical analysis on shifting process and synchronization model. Then, a virtual prototype of the manual cycle shift mechanism was established, with software CATIA, Sim Designer and ADAMS, refer to CCG8 flame diesel engine locomotive. The shift performance of manual cycle shift mechanism was analyzed, based on the shift force curve, obtained from dynamic simulation of upshift and downshift. The influence of shift speed and groove cam angle on shift force was analyzed, too. The results obtained were as follows:(1) The secondary impact force/maximum shift force ratio of 1-2 shift up process and 2-1 shift down process were slightly larger. The maximum shift force and secondary impact force of other shift process met the requirements, which showed that driver can complete the shift operation comfortably. The manual cycle shift mechanism had relatively good shift performance.(2) The faster shifting, the larger maximum shift force and secondary impact force, and the smaller decline in speed.(3) The larger groove cam lead angle, the larger maximum shift force and secondary impact force. Shift performance and structural dimensions should be both fully considered in the design of groove cam lead angle. In the end, this paper summarized all of the work involved in the project and gave prospects for the later study work.