Eight-speed automatic transmission

The utility model discloses an eight-speed automatic transmission, which belongs to the field of transmissions and comprises four groups of planet rows, namely a first planet row, a second planet row,a third planet row and a fourth planet row from left to right in sequence, and each of the four groups of planet rows is provided with a sun gear, a gear ring, a planet carrier and a plurality of planet gears. A new power transmission scheme of the eight-speed automatic transmission comprises three overdrive gears, the transmission ratio range is wide, the transmission efficiency of the automatictransmission is effectively improved, the fuel economy is improved, the harmful gas emission of tail gas of a vehicle is reduced, the eight-speed automatic transmission can be assembled on a rear-drive vehicle, and the power performance of the vehicle is further improved. 本实用公开了一种八速自动变速器，属于变速器领域，变速器包括四组行星排，从左往右依次为第一行星排、第二行星排、第三行星排和第四行星排，所述四组行星排均设置有太阳轮、齿圈、行星架及若干个行星轮。本实用变速器的新动力传递方案中包含有3个超速档，且传动比范围广，将有效改善自动变速器的传递效率、提升燃油经济性、降