The Transmission Inprovement And Experimental Research Of 5t Wheel Loader

In this paper, the author researches on the current level planetary gearbox 5t ZL50 loader that used commonly used in domestic based on the technology projects of a loader company,, proposed and do some improvement after analyzing the common fault and the relevant parameter calibration to increase the reliability with long service life and less transmission fault. This is a transmission technology improvement projects Applied on the loader. This article the author does some researching analyzing on was the following field.1) Reviewed the status of gearbox loader, the purpose and content needed to research, draw on the experiences of the existing technologies and methods of the 5t class gearbox loader, design of. In its theoretical basis, collect the common failure modes then collect some common faults and its reason and provide the raw material for the improvement.2) Structure optimization and intension analysis of the key parts on modified gearboxUnder middle levels of the application and manufacturing of working pump, steering pump and variable-speed pump, the compressional stress of spline joint should be less than the allowable value, according to the actual working of loader and the practical manufacturing of engineer machinery; contact stress of the overrunning clutch is calculated adopting the maximum stalling output moment of the torque converter; the strength can meet the demand by the optimal design of"three in one"bolted connection, joint bolts between the direct gear shaft and second gear ring and joint structure of connecting-disk; by optical structure design of disc spring, its life is tested enough; through the calculation of delivered torque, the torque of friction disc meets the requirements. By compared, it is observed that the modified gearbox is better than the original ZL50 in crucial parameter, such as intensity and lifetime.3) 0ptimization design and strength analysis of the speed changing box's structureBearing pedestal displacement response curve of the V axle was get from finite-element analysis of the speed changing box's structure in the first gear working condition. Reckoning and displacement distribution of model conformed the physical truth, it proved that the response model and calculation of the speed changing box were correct. The texture of the box was reasonable, casting flaw must be strict controlled in the stress area, rib plate distribution that was changed was the best for the vibration. It reduced the vibration of part for output flange. This text suggested keeping the overall arrangement of part for output flange and adopting reversible deformation measure. According to difficulty of technology implementation plan, the torus restrain of five axle box, increasing rigid fixed support of loader frame, the cost and improvement, the foregone condition of overall structure layout, the reduction of output end stoppage of the five axle box, the improvement of weak structure and rib plate distribution, the mature direction of reducing transformation and mirror of the box leakproof structure at home and abroad, this article adopted back-to-back installation, import oil seal material and reasonable process assembly method.4) Experimental study of speed changing boxAccording to experiment qualification of improved speed changing box, this text used pilot system of speed changing box and improved speed changing box sample to do no-load power loss, oil control valve, shift process, transmission efficiency, temperature rise and reliability test. Improved suggestion was put forward for optimization design from the function, reliability assessment and comparative analysis with ZL50 speed changing box.(1)Because of the low efficiency of the torque converter and low processing precision of the gear, the No-load power gearbox loss is too large and the efficiency is too low, so we recommend that increase the level of precision gear parts in order to improve efficiency reduce noise and vibration.(2)The operation of improved wedge-type clutch is in a good condition during a heavy load cycle test and a reliability test.(3)Strengthen the quality control of the assembly of the oil seal and the seals because of the oil leak of the gearbox output shaft.(4)No abnormal be seen after improved test of the remaining parts, suggest that small batches assembly to try.Through extensive understanding and loader transmission manufacturing technology at home and abroad, careful analysis 5-ton loader gearbox failure parts easy appeared, according to the theory mechanism theoretical calculation and test results, this paper puts forward a positive and effective and implement structural optimization, manufacturing process control. After verification test each index all gearbox ZL50 than the original planet type gearbox, achieve the expected effect.