DESIGN AND EXPERIMENT ON CUTTING AND CRUSHING DEVICE OF SIDE-SWEEPING STRAW RETURNING MACHINE

This paper aims to solve the problems of complex structure, poor straw crushing effect and high power consumption of existing straw returning machines. A cutting and crushing device with moving and fixed blades has been developed. The moving blade has collision and automatic retraction functions, which can effectively reduce destructive damage caused by blade obstacles and extend its service life. The double-type single-support cutting method has the advantages of improving the straw crushing effect and reducing the running power consumption. The effects of blade rotational speed, blade offset angle and blade number under the condition of composite single-support cutting were tested according to the uneven ratio of straw throwing and the qualification ratio of straw crushed length. The optimal combination of working parameters of the cutting and crushing device was determined: blade rotational speed of 1968 r/min, blade offset angle of 5°, blade number of 4. The test results show that the uneven ratio of straw throwing is 17.18%, and the qualification ratio of straw crushed length is 92.23%. The operation effect of the side-sweeping straw returning machine was tested on the field. All operating indicators are equipped with cutting and crushing devices, and the results show that all operating indicators meet the technical requirements of straw return.