Assembly line of the latest loader

In the past, the assembly method of decentralized positioning has been used for the assembly of construction machinery in the assembly line of the new loader. The assembly quality of this way is random and labor-intensive. With the development of production and the increase of production batch, most manufacturers have installed assembly lines. However, due to the general characteristics of high quality and large size of construction machinery, some structural types of assembly lines are not suitable for the assembly of construction machinery. As a result, some enterprises have installed assembly lines, but the purpose of improving the assembly has not been achieved. The use of assembly lines is inconvenient, or even impossible to use at all. Based on the investigation and design and construction experience of the whole assembly line of construction machinery, the author introduces a kind of practical structure, that is, the whole assembly line of the chain driven underground automatic return loader

the wiring of the machine adopts a single chain to drag the assembly trolley, so as to realize the underground automatic return of the assembly trolley. The offline position of the whole machine adopts the method of combining the offline pedal with the slow descent of the chain to realize the automatic offline of the workpiece. The assembly line with this structure is suitable for the complete assembly of ZL30, ZL50 and ZL60 loaders. We firmly believe that China's analytical instrument industry will be more and more robust, and the maximum mass of online workpieces is 17.3t. According to the process requirements, the station spacing is determined to be 8100mm. There are 13 assembly stations, and the assembly of a complete machine is completed in 45min. According to the calculation of 8h per shift every day, 10 loaders can be assembled, and the assembly task of 2500 loaders can be completed throughout the year. The line length (the distance between the center line of the driving wheel and the center line of the tensioning wheel) is 108m, the chain pitch is 300m, and the total length of the chain is 218.4m. The assembly line uses two assembly trolleys to support a workpiece, and the fulcrum is on the front and rear axles. According to the different workpieces, the center distance of the front and rear assembly trolleys can be adjusted by moving the rear assembly trolleys. Among them, the support surface of the rear assembly trolleys is set up with many listed companies such as BYD, Shanshan, dadongnan, camel, etc. to add lithium battery investment into a plane, so as to fine tune the support distance. The connecting block is fixed on the chain, and the assembly trolley is connected with the infinite chain potential. The connecting block is connected with a pin shaft. The center distance between the front and rear assemblies can be easily adjusted to 2700, 3000 and 3300mm to meet the needs of Z30, ZL50 and ZL60 loaders respectively. In order to adjust the support width, the assembly support is designed to be adjustable and fixed on the trolley with bolts. The thickness of the support plate is 20mm. When the distance of the current rear axle support width is adjusted to 800-900mm, it can meet the needs of the assembly line of various products. The height of the trolley is fixed at 840mm, of which the height of the bracket is 420mm, as shown in Figure 1

due to the automatic return under the assembly trolley, a pit must be dug under the assembly line. This requires erecting the trolley, track, etc., and the weight of the workpiece will also act on it. We set a beam every 1.5m. The beam is made of I20, and both ends sit on the pit wall to replace the huge steel structure support. This reduces the width of the pit and the convenient price of equipment manufacturing and operation. When the assembly trolley returns, a return track is set, which is fixed on the pit wall. Considering the large size error of the pit width, the track is made adjustable in the width direction. The trolley is equipped with auxiliary guide wheels. The auxiliary guide wheel runs on the return track and is used for support and guidance when the trolley returns underground

the guide wheel of the traction chain is the bearing wheel, and the guide rail is set on the ground. When returning underground, the traction chain is supported by the assembly trolley

the drive device of the assembly line adopts cycloidal pinwheel reducer for deceleration, and the reducer is connected with the drive sprocket shaft by elastic pin coupling. The power of the drive motor is 7.5kW, and the motor is directly connected with the reducer. The sprocket shaft is tensioned by the lead screw nut tensioning device

the lower line station is equipped with lower line pedal, which is 120mm high, 800mm wide and 3800mm long. It is welded by profile steel and checkered steel plate. The off-line pedal is fixed after selecting the best position based on the specific situation of each product when it is off-line. The chain of the off-line station slowly drops, the workpiece tire slowly falls onto the pedal, and the assembly trolley gradually disengages from the workpiece, realizing the automatic off-line of the workpiece

the putting into use of the whole assembly line of the underground automatic return loader of the linked mobile trolley has changed the previous decentralized fixed position assembly method, realized the specialized assembly, improved the production efficiency, reduced the labor intensity of workers, and adapted to the requirements of enterprises for batch production and efficiency. The underground automatic return of the assembly trolley reduces the transportation and logistics volume of the workshop and improves the utilization rate of the workshop. The workpiece is automatically offline, which reduces the tonnage of the crane in the workshop and significantly reduces the cost of the plant and lifting equipment. Using the beam fixed on the foundation as the bearing frame to replace the heavy steel structure support saves a lot of steel. Since the assembly line with this structure was put into use in May, 1994, it has been widely used in the assembly of loaders and bulldozers in many domestic construction machinery plants, and has achieved good economic and social benefits