The lower boom and the upper boom of the three boom wheeled hydraulic excavator are connected by a pin shaft, and a combined boom cylinder is added between the abdomen of the lower boom and the lower part of the upper boom. Through this cylinder to adjust the angle between the upper and lower boom, stepless adjustment can be realized, and the adjustable range is up to 45 degrees. Compared with the wheel type hydraulic excavator equipped with the first two working devices, the three boom wheel type hydraulic excavator has the following advantages.
1. In the construction process, the overall length of the boom can be adjusted at any time according to the working conditions, so the operation is very convenient and fast, without disassembly.
2. Due to the high driving speed of the tire excavator, after the upper boom is retracted, the center of gravity of the whole working device moves back into the front wheel. When encountering emergency braking, the driver will not feel the fear of rolling forward, which is safer.
3. After the upper boom is retracted, the length of the whole machine becomes shorter, the turning radius is reduced, and the driving vibration becomes smaller.
4. It can expand the maximum vertical excavation depth of the whole machine, that is, it can reach a larger depth in a smaller excavation area.
