The knife rest in the cutting and crushing device is an important bearing part in the straw cutting square baler, which impacts the performance of the straw cutting square baler. In order to avoid the problem of insufficient structural strength and resonance of the turret during the operation, a threedimensional model of the straw cutting square baler was established by using SolidWorks software, and the simplified turret model was imported into ANSYS Workbench software for static and modal analysis. The static analysis results showed that the maximum displacement and stress of the tool holder under static load were 0.259 3 mm and 54.77 MPa, which were less than the yield strength limit of Q345. The modal analysis results showed that the range of the first 20 natural frequencies of the cutter head was 32.61-257.83 Hz, which was different from the excitation frequency 0-15 Hz generated by the tractor, so the straw cutting square baler will not produce a resonance phenomenon during operation. The field test results showed that the pure working hour productivity of the straw cutting and kneading square baler was 4.49 t/h, the baling rate was 985%, the regular straw baling rate was 97.01%, and the fall resistance rate was 95.52%. The test indexes met the test requirements, and the comprehensive performance of the tool rest met the design requirements.

As a multi-excitation source vibration system in a complex farming environment, the vibration mechanism of the silage corn harvester is difficult to be thoroughly described theoretically. To investigate the analysis methods suitable for studying its vibration characteristics, a silage corn harvester test bench was built in this paper. A 24-bit INV3062-C1(S) general-purpose dynamic test and acquisition instrument was used to test the vibrations of the kneading roll, the fixed knife, and the frame position at different speeds. The mean, variance, and RMS values of the vibration amplitude of the test bench were analyzed. The vibration signal could be approximated as conforming to the characteristics of smooth random vibration. The time-domain characteristics and vibration frequency distribution law of the vibration under different working conditions were obtained. The results show that with the increase of motor speed, the vibration intensity of the whole machine increases, among which the vibration amplitude of the kneading roller position is the largest, the frame is the second, and the fixed knife is the smallest. Under the straw feeding condition, with the increase of speed, the rate of the frame amplitude is higher than that of the kneading roller and fixed knife, and the frame is the most sensitive to the change of motor speed. The influence of corn straw feeding on the vibration of the test bench is larger at low speed (900 r/min) and medium speed (2 000-4 000 r/min), and less at high speed (4 500 r/min). The vibration frequency of the test stand is concentrated in the range of 166.7-185 Hz, 250.7-269.6 Hz, 527-559 Hz, 746.8-776.2 Hz, and 872.9-904.8 Hz, which is mainly the multi-frequency component of the motor rotation frequency. At medium and high speed, the vibration of the motor has a greater impact on the vibration of the test stand and has less impact in the low-speed state. In the design of silage harvester, consideration can be given to arranging reinforcement bars at the frame position and adding vibration isolation between the silage harvester frame and the engine to reduce the impact of vibration on the silage corn harvester. The study results can provide a reference for reducing the vibration of the whole machine of the silage harvester and for the design and optimization of the harvesting machine in the complex farming environment.