Design of variable speed smashing rotary tiller
introduction
China is a large agricultural country, suitable for grain planting area of ​​about 7.5Mhm2, and the total amount of straw produced by wheat, corn and other crops exceeds 500 million tons per year. According to the farming habits of farmland in China, crops must be kept at a certain height after harvesting. A large amount of stubble can not be used, but affects farmland farming. In order to remove these straws and stubble, farmers often use incineration methods. In North China, Northwest China and Northeast China, after the autumn harvest, farmers have caused atmospheric pollution caused by burning straw, which has affected the safety of the navigation channel. Many provinces and cities have to issue straw bans after autumn. The key to eliminating straw burning is to grasp the comprehensive utilization of straw. Practice has proved that the direct returning of crop straw and stubble by mechanization is an important measure to increase organic matter, fertilize soil fertility, improve soil structure, enhance water retention and fertilizer retention capacity, and improve soil. It is also to protect the environment, develop ecological agriculture, and realize organic agriculture. And an important guarantee for sustainable agriculture. The research and development of the scientific and technological research project undertaken by Nanchang Mining Machinery Research Institute-80 type smashing rotary tiller has absorbed advanced technology from home and abroad and carried out technological innovation. It has successfully developed a dual function of both rotary tillage and shallow tillage. The speed change smashing rotary tiller. The project passed the expert appraisal and declared the national patent ZL02277449.1.
1 Structural features of the variable speed rotary tiller
1) The power output shaft of the south tractor of the machine enters the transmission box (3) through the universal joint shaft (1) and the transmission input shaft (2), and passes through the shifting handle (9) on the transmission box (3) It can quickly, easily and easily change the rotation and speed required for the tool during rotary tilling and smashing operations.
2) When the variable speed rotary tiller is used for rotary tillage operation (as shown in Figures 1(a), (b) and (e)), the power is transmitted from the tractor power output shaft through the power input shaft in the gearbox (3) ( 2) The input of the universal joint shaft (1) is transmitted to the shift gear (6, 7) which is respectively meshed with the power input shaft (2) and the end of the spline shaft (16). ). Rotating the shifting handle (9) mounted on the outer wall of the transmission case (3) and inserting it on the spline shaft (16) through the connecting rod and the shifting fork (15) inserted into the side groove of the shifting gear (8) A slippable shifting gear (8) that meshes with the double large gear (14). The double large gear meshes with an output gear (12) mounted on the output spline shaft (11), and the cutter shaft (21) is immediately adjacent to the outer side of the transmission case (3) by means of splines and bolts (23), and outputs splines Both ends of the shaft (11). At this time, the rotation speed of the cutter shaft (21) is low (200r/min or 267r/min), and the rotation direction is the same as the steering of the drive wheel when the tractor advances, which is suitable for the rotary tilling operation.
3) When the variable speed rotary tiller is used for shallow tillage operation (as shown in Figures l(c) and (e)), the shift gear (8) mounted on the spline shaft (16) is slidable. The reverse gear (10) is engaged, the reverse gear (10) is meshed with the double pinion (13), and the power is transmitted to the output spline shaft via the double large gear (14) meshing with the output gear (12) (1) 1) and the cutter shaft (21) fastened at both ends of the output spline shaft (11). At this time, the rotation speed of the cutter shaft (21) is high (415r/min or 554r/min), and the rotation direction is opposite to the steering of the drive wheel when the tractor advances, which is suitable for the smashing operation.
4) Shaft end seal of the variable speed rotary tiller (see Figure 1(d)), sealed with a shaft seal (17) with a 0 type seal (18) and a hole with a skeleton oil seal (20) The combination seal formed by the ring (19) effectively blocks the leakage of the lubricating oil in the transmission case (3) and the intrusion of water, sand and weeds, straw and the like in the field. The machine is equipped with a hood (4) for blocking the sediment on the upper part of the cutter shaft (21), which improves the working environment, and the cutter (5) is inserted into the square hole of the seat (22) on the cutter shaft (21) (see the figure). 1(e)), and fastened with bolts (23) and (24), it is very convenient to disassemble.
2 Features of the variable speed smashing rotary tiller
The traditional rotary tiller for wheeled tractors is mainly to complete the rotary tillage operation, and the smashing machine is used to break the stubble roots in the shallow soil, and they all have a single function. The variable speed shovel rotary tiller has the function of reversing and shifting on the same machine. As long as the shifting handle on the transmission box is toggled, the rotation and rotation speed required for the rotary tilling and smashing operations can be changed quickly, conveniently and easily. It is a new product that combines rotary tillage and shallow tillage. Its features are as follows:
1) During rotary tillage operation (the rotation direction of the cutter shaft is in the same direction as the forward direction of the drive wheel, the rotation speed is 200r/rain or 267r/min), which can be used for crushing soil in uncultivated or plowed fields, and has strong soil-breaking ability. It has the characteristics of smooth surface, tight coverage and high work efficiency after ploughing, and can be used in dry land or paddy field operations.
2) Shallow tillage and cockroach function. Most of the crop-producing areas in China have the habit of leaving their crops after harvest. The corn borer, wheat bran, sorghum or rice bran left in the ground is not only difficult to rot, but also affects the quality of the next planting and planting process. Shallow ploughing and hoeing is to use the reverse rotation tillage (rotation speed 415r/min or 554r/min) before the deep ploughing to shovel the surface layer of 4~8cm, and break the root stalk left on the surface to prepare for the subsequent cultivation.
3 Evaluation of variable speed smashing rotary tiller
The variable speed smashing rotary tiller has the characteristics of the rotary cultivator type intermediate transmission which is widely used in China. The transmission mode is unique, and it has the functions of forward rotation and reverse rotation, low speed and high speed. It successfully solves the problem that the two operation modes require different rotation speeds and rotation directions of the cutter shaft. It is based on the IGQN series rotary tiller. The new land preparation machine, which combines the functions of rotary tillage and cockroach, not only increases the cockroach function, but also retains all the advantages of the original rotary ploughing operation. The whole machine has compact structure, stable center of gravity, dual-purpose machine, easy operation and high degree of generalization of parts.
It is predicted that there will be more than 250,000 rotary cultivating and annihilating agricultural machinery in the country each year. The variable speed smashing rotary tiller has a dual-purpose machine and convenient shifting, which reduces the user's investment and simplifies the management of agricultural machinery. It has a large competitive advantage in the domestic ploughing and agricultural machinery industry, and has good promotion value and development prospects.