Hard shaft transmission is adopted, mainly composed of engine, transmission system, clutch, working parts, control device and side-hung belt. One end of the transmission shaft is equipped with a 0.75~2kW single-cylinder two-stroke air-cooled gasoline engine and a centrifugal friction clutch; The other end is installed with a working part consisting of a reducer and a cutting tool. There are many types of working parts, usually circular saw blade, blade or nylon wire. During operation, hang the shackle on the aluminum alloy sleeve of the transmission shaft on the shoulder strap under the operator's shoulder, hold the handle, and swing the hard shaft horizontally to complete the operation of cutting weeds and shrubs. The weight of the implement is about 6-12 kg, and the rotational speed is about 4500-5000 rpm.
It is driven by a flexible shaft. The general structure is similar to that of a side-hung irrigation cutter. The difference is that its engine is on the back of the operator, and the cutting parts are driven by a flexible shaft. The engine power is generally 0.75~1.2 kW. The engine and the back frame are connected by two points and equipped with special rubber parts for vibration isolation. The flexible shaft is a steel wire flexible shaft wrapped in a hose to transmit torque. The hose is a threaded pipe wrapped by a steel belt wrapped by a metal woven mesh covered with a rubber protective sleeve to prevent dust from entering the shaft and keep the lubricating oil on the shaft surface. The cutting width is generally between 1.5 and 2 meters.
The weight of the implement is supported by the traveling wheel, the machine is pushed forward by a person, and the working parts are driven by the engine for cutting and filling operation. Its structure and working principle are similar to those of portable brush cutters. The hanging harvester is hung behind the tractor and driven by the power output shaft to rotate the working parts. It is suitable for large area cutting and irrigation work. It is mainly composed of frame, saw blade, transmission device, suspension device and push plate. When cutting irrigation, the tractor moves backward at a working speed of 5 km/h and can saw shrubs with a diameter of 10 cm.
The horizontal header harvester is composed of a reel, one or two front and rear canvas conveyor belts, a divider, a cutter and a transmission device (Fig. 1). During operation, the reciprocating cutter, with the cooperation of the reel press plate, cuts the crop and reverses it on the canvas conveyor belt, which sends the crop to the left side of the machine. Because the rear conveyor belt is longer than the front conveyor belt, the ear head part falls late, so that the discharged straw is laid on the ground into a neat straw at an angle to the machine's travel direction, which is convenient for manual picking up and bundling. The horizontal header harvester has good adaptability to different growth density, plant height, lodging degree and yield of rice and wheat, with simple structure; However, the longitudinal size is large, and the flexibility of the operation timing group is poor. Most of them are matched with wheeled or walking tractors below 15 kW. The cutting width is less than 2.0 meters, and each meter of cutting width can harvest 4 to 5 mu of wheat per hour.
The crop cut by the vertical header harvester stands upright on the cutter plane, and is laid into strips close to the conveyor outside the output machine. There are two types of side paving and rear paving: the side paving harvester is composed of a divider and a reel star wheel (or reel thumb wheel), a cutter, and a transverse vertical toothed belt conveyor. The cut crop is pulled by the reel to the upper and lower toothed belts of the conveyor, and the conveyor will transport it laterally to the side of the machine for paving. The rear-laying harvester (Fig. 2) adds a group of reeling triangle belts, star wheels and crimping spring strips with teeth every 30 cm between the two dividers to keep the straw in a stable and upright state during the transverse conveying process. When it reaches the right side of the machine, it is conveyed backward by a pair of longitudinal conveyor belts. The straw is laid into strips at the rear of the machine with the cooperation of the crimping plate. Under the condition of interplanting corn, this type of machine can not press the straw on the corn seedling, and its cutting width is equal to the wheat border width between two rows of corn. The vertical header harvester has compact structure, small longitudinal size, portability and flexibility, and good handling performance. It is suitable for harvesting rice and wheat on small plots. Most of them are matched with walking tractors of 7~9 kW or wheeled tractors of about 15 kW, with a cutting range of 1.1~1.2 meters; There is also a small self-propelled harvester with a cutting range of about 1 meter, which is matched with a special chassis of 2~3 kilowatts.