Device and method for intelligently controlling ball throwing by aid of gears for multi-stage horizontal well fracturing

The invention discloses a device and a method for intelligently controlling ball throwing by the aid of gears for multi-stage horizontal well fracturing. The device comprises an annular pipeline, a ball throwing module, a ball throwing detecting device (6) and a liquid collecting device (14). The annular pipeline comprises a fracturing liquid main pipeline, a special-shaped connecting pipe (4), an annular connecting pipe (18) and a straight connecting pipe (17), the special-shaped connecting pipe (4), the annular connecting pipe (18) and the straight connecting pipe (17) are sequentially communicated with one another to form a U-shaped through pipe, the fracturing liquid main pipeline comprises a large-diameter section (9) of the fracturing liquid main pipeline and a small-diameter section (10) of the fracturing liquid main pipeline, a side of the large-diameter section (9) of the fracturing liquid main pipeline is communicated with the special-shaped connecting pipe (4), the special-shaped connecting pipe (4) is communicated with the liquid collecting device (14), and the ball throwing module is arranged above the special-shaped connecting pipe (4). The device and the method have the advantages that repeated ball throwing can be remotely controlled during multi-stage fracturing without pump stopping, ball throwing sequences can be adjusted, the ball throwing success rate is high, and the device is convenient to use and can be reused.