Abstract:
Small arch sheds have been widely constructed in manual in China at present, particularly with the high labor intensity and low efficiency. The current commercial machinery of arch shed is the traction type in the form of shutdown insertion during construction. It is a high demand to improve the efficiency in the operation of shutdown insertion for the construction machinery. In this study, a continuous cuttage device was developed in the self-propelled shed machine for arch building. Specifically, the rear motor of the vehicle was used to drive forward, where the rear wheel drove the continuous insertion device to rotate via the transmission device, thereby driving the continuous insertion device to work. According to the agronomic requirements and overall structure, the key components of the continuous insertion device were determined to optimize the parameters of reverse transmission mechanism and bending components of the planetary gear train using simulation. The continuous and stable insertion operation was achieved to reduce the machine wear that caused by shutdown insertion for the high efficiency of arch construction. The reverse transmission mechanism and bending components of the planetary gear train were then designed to drive the bending components for the rotation and actions, such as bending and pressing poles. The soil resistance of shed pole was set as 51 N, when the maximum depth of insertion into the soil was 10 cm, according to the discrete element simulation of "Shed Pole-Soil". The stress simulation was conducted on the pressure pole arm of the shed pole and bending components, in order to ensure the successful insertion of the shed pole into the soil. The simulation results showed that the friction force between the pressure pole arm and the shed pole was 168 N, which was much greater than the soil resistance suffered by the shed pole. Moreover, the stress of shed pole was within the yield strength at the same time. The trajectory of bending pressure plate was analyzed in the bending components, according to the agronomic requirements of the depth and spacing of the small arch shed insertion. The optimal length of bending bracket was determined to be 27 cm, and the ratio of the speed of the central rotating shaft to the travel speed of vehicle was 0.85. The field trail results showed that the average insertion depth and spacing of shed pole were 7.04 and 74.11 cm, respectively, where the average error were 0.09 and 0.16 cm respectively. Therefore, the continuous insertion device of the self-propelled arch shed machine was developed to determine the optimal parameters of planetary gear train reverse transmission mechanism and bent parts using simulation. The continuous and stable insertion can be expected to reduce the wear of the machine that caused by the shutdown of the arch frame, particularly for the high construction efficiency of arch shed.