Chainsaw development

A hand-held wood cutting machine powered by a gasoline engine, the saw chain is the cutting part. In forestry production, it is widely used in logging, branching and logging operations.

General: In 1914, Germany made the world's first chain saw with a power of about 3 kilowatts and a weight of 80 kilograms. It was carried by two people. In the early 1950s, with the widespread use of small internal combustion engines, the Soviet Union, the United States, the Federal Republic of Germany, Sweden and Japan began mass production of single-acting chain saws. By the 1960s, due to the development of light alloy die-casting technology, the sawing industry had greater development. China was established in 1956 and began production in 1957.

Classification: According to the type of saw handle, it can be divided into two types of chain saws, high saw and low saw (see picture). The weight of the chain saw is evenly distributed on the arm for easy carrying. No big bends are needed during operation, and machine maintenance is simple. The short chain saw has a compact structure, light weight and little vibration during operation. Suitable for mountainous forest areas. Comprehensive operations, such as logging, branching and building materials. According to the engine power, it can be divided into large, medium, small and micro: greater than 4.4 kilowatts; medium to 3 to 4 kilowatts; small to 1 to 2 kilowatts; less than 1.5 kilowatts.

Basic structure: usually composed of engine, transmission mechanism, sawmill factory, etc. During the operation, the power drives the saw chain through the transmission mechanism, so that the saw chain can continuously saw the wood along the guide plate.

1 engine. It is usually a single-cylinder air-cooled two-stroke high-speed gasoline engine. In order to adapt to the operation of the chain saw at different positions in different sawing directions, the pump membrane carburetor with an oil pump is used to drive the diaphragm pump oil by the pressure pulsation in the crankcase so that the engine can work normally. Provide in any location. . In addition, new structures such as transistor non-contact electromagnetic ignition systems and check valve air intake systems are increasingly used to improve engine performance.

2 Transmission mechanism. Including centrifugal friction clutch and reducer. The reducer generally uses a bevel gear reducer (only applicable to high-lift chainsaws), which is beneficial to the horizontal and vertical adjustment of the sawing mechanism relative to the body to meet the needs of different sawing directions when logging and building materials.

3 Sawmill mechanism. It is the working part of chain saw, including driving sprocket, chain saw, guide plate, chain saw tensioning device and inserted wooden teeth. The drive sprocket rotates under the drive of the engine and drives the saw chain along the guide plate to perform the cutting operation. There are two types of saw chains: straight tooth type and angle steel type (universal type). Straight tooth saw chains are suitable for cross-section wood; angle steel saw chains can be used for wood cross-sections or miter saws. They are simple to manufacture and relatively honing. Straight tooth saw chains are simple and are widely used saw chain types. Inserting wood teeth is the supporting point of sawing wood during sawing. When the saw chain cuts the sawn wood into wood, the wood saw will bear part of the weight and reaction force of the sawn wood, thereby reducing the labor intensity of the operator. For ease of operation, the chain saw is also equipped with a steering device including a handle.

Development trend: the use of new materials, new processes, new structures to further reduce the weight of the saw; reduce noise and vibration and reduce air pollution to improve operating conditions; increase safety protection devices to improve the reliability and safety of use; by rotation The new chain saw and remote chain saw powered by the engine will continue to be improved.