How a flail mower works
The flail mower:
A forage harvester that cuts grass or other hay crop and lays it on the ground.
There are reciprocating and rotmowerary types.
Reciprocating mower:
The forage is cut by the relative shear movement of moving and fixed knives on the cutter. It is characterized by neat stubble cutting and less power per unit cutting width. However, it has poor adaptability to different growth states of herbage and is easy to clog. Suitable for flat natural grassland and artificial grassland of general yield. Due to the large vibration of the cutter during operation, the improvement of operation speed is limited. Moving knife cutting speed is generally less than 3 m/s, operation speed is generally 6 ~ 8 km/h.
Tractor-mounted flail mower:
The structure is simple, light and flexible. There are three kinds of front-mounted, side-mounted and rear-mounted mowers, and the later-mounted mowers are the most widely used. Reciprocating mower is composed of cutter, cutter transmission device, cutter lifting device, safety device and grass retaining device. The operating principle and construction of the cutter is basically the same as that of the grain harvester. The blade used has two kinds of light blade and tooth blade. Generally adopt light blade moving blade. Cutter transmission device is similar to grain harvester, mostly using offset crank connecting rod mechanism and swing ring mechanism. Because of the high growth density and high moisture content of herbage, the average speed of moving knife is higher than that of grain harvester, which is generally 1.6 ~ 2.0 m/s. Cutter lifting device is generally controlled by hydraulic system, lifting quickly, convenient, can ensure the adaptability of cutter to complex ground. Safety device is mainly to ensure the safety of transmission device and cutter. For mowers with high working speed, decoupling safety devices are generally used. When the cutter resistance is too large, the safety device automatically decouple, the cutter swings back, and cuts off the power of the cutter. The driving device of some flail mowers adopts wooden connecting rod or adhesive tape driving mode, and the connecting rod breaks or the adhesive tape slips when overloaded, so as to protect other driving parts and the cutter from being damaged. The grass retaining device is usually installed on both ends of the cutter or the outer end of the grass retaining board, its function is to move the cut grass to the middle of the cutter for a certain distance, leaving a passage for the next trip of the tractor wheels through, to avoid or reduce the rolling of the cut grass.
Rotary mower:
Impact cutting of forage grass by means of blades on a high speed rotating cutter head. Cutting speed (the circumferential speed of the blade root) up to 60 ~ 90 m/s. The work is smooth, and the working speed can reach more than 15 km/h. It is characterized by strong adaptability to herbage and is suitable for high-yield pasture, but it is not neat enough to cut, more recutting and more power per unit cutting width.
Rotary mower:
Flail mower, rotary mower
There are two kinds of drum type and rotary disc type: (1) the transmission device of the drum type lawn mower is located above the cutter, so it is also called the rotary mower. A drum mower is generally equipped with 1 ~ 4 vertical cylindrical or conical rollers in parallel. Each roller is equipped with a cutter head hinged with 2 to 6 blades, and the rotary track of the blades on the adjacent cutter head has a certain amount of overlap to avoid missing cutting. The roller is driven by tape or bevel gear, and the two adjacent rollers rotate relative to each other. The cut grass is sent down by a pair of rollers and placed backward into neat strips of grass. Can meet the requirements of low cut, but the structure is not compact enough. The driving device of the rotary mower is located below the cutter head, so it is also called the rotary mower. On the blade beam of rotary lawn mower, there are generally 4 ~ 6 knife discs in parallel. Each cutter head is hinged with 2 to 6 blades. The configuration of the blades on the adjacent cutters is staggered with each other, and the rotation track of the blades has a certain amount of overlap. The cutter head is usually driven by gear, and the direction of the adjacent cutter head is opposite. Compact structure, smooth and reliable transmission. But the cutter head is higher because of the transmission underneath. To ensure low cutting and reduce heavy cutting, the cutter head is usually tilted forward at an Angle. A hinged blade on the cutter head of a rotary lawn mower that maintains its cutting state under centrifugal force when the cutter head rotates at high speed. When the resistance is too large or encountered obstacles, the blade will swing back to avoid damage. If one edge of a blade is worn, it can be used on another side. It is also easier to change blades than reciprocating mowers. In rotary mower, in addition to equipped with reciprocating mower similar to the safety device, in the cutter above the protective cover, to ensure personal safety. Rotary mowers rely on blades on high-speed rotating blades to impact the cutting grass. Cutting speed (the circumferential speed of the blade root) up to 60 ~ 90 m/s. The work is smooth, and the working speed can reach more than 15 km/h. It is characterized by strong adaptability to herbage and is suitable for high-yield pasture, but it is not neat enough to cut, more recutting and more power per unit cutting width.
