GM brand has a number of new cars have all match the latest 9AT transmission, many people think that multi-gear transmission can reduce fuel consumption, the fact is true, but the general replacement Sensor of 9AT there is a reason, that is, 6AT frequent accidents, seriously affected Its variety of models in China sales.
In the just listed near the Chevrolet delchers on the high, equipped with the latest 9AT transmission. As for the upcoming listing of the Buick Regal will also match the latest 9AT transmission, which means that the future can really and 6AT say goodbye. However, for the domestic auto market, 9AT is not so good, earlier equipped with 9AT Land Rover aurora, Freelander and free light have emerged a variety of problems, and even topped the 315 party stage, can be described as bright stars. At present, the domestic can buy matching 9AT models are not many, Land Rover, Jeep, Honda Temperature Sensor are used from Germany ZF 9HP gearbox, and Mercedes-Benz is the use of their own research and development of 9G-Tronic automatic transmission, Chevrolet has only five brands using 9AT, and 9AT only three types.
Rong Tan 315 party 9AT transmission is from the famous ZF, in fact, ZF 9AT is not really a problem but rather its pursuit of economy. For large displacement models ZF 9AT match degree will be better, and small displacement matching some far-fetched, and the domestic road situation is more complex. For multi-range transmissions, the gear ratio of the gears can be made smaller as the number of gears can be made smaller, and the speed of the high-speed cruise engine is lower and the fuel economy is lower. While the wider tooth ratio is more advantageous for dynamic performance, maintaining the highest performance output speed over a wider range of speeds. So the multi-gear transmission balance the performance and fuel economy, but more gear means more complex, especially the range between the teeth, miniaturization and lightweight. Universal 9AT transmission compared with only two super gears for high-speed cruise, 1 to 7 stalls between the stall smaller, and 9AT gear ratio than 6AT gear ratio, reached 7.56: 1 , Thus taking into account the speed performance and high-speed cruise fuel economy. At the same time, the more dense teeth ratio makes the explorer in 95km / h will be able to 9 gear, and has four overdue ZF in the domestic speed limit 120km / h case is difficult Pressure Sensor to play the full advantage of the transmission. In contrast to ZF, the advantage of a conventional transmission is that the gears are more dense, the gearshift process is smoother and the gear utilization is higher.
General this 9AT transmission still has a problem, can only be applied to the horizontal platform. Due to the stability of the power platform layout space, so 9AT must reduce the total length of the gearbox and the overall volume. To this end, this 9AT redesigned the gear and the reverse gear part of the clutch. In addition, the general 9AT using the axis of the layout, all the gears in a straight line on the input shaft, making the overall space is more compact. At the same time, GM 9AT to increase a start and stop the energy storage device, the main internal and external energy storage by the spring and oil tank composition. Before the engine is turned off, the oil has pre-poured into the oil chamber to tighten the spring Throttle Position Sensor so that the spring has energy. At the moment of the start of the vehicle, the accumulator releases the elastic energy to 'squeeze' the oil in the chamber to ensure that the gearshift mechanism can quickly switch to the first gear, resulting in a more smooth use.
The new 9AT transmission is GM's current future models will be widely used, this transmission in the shift logic and tooth ratio adjustment between the better than 6AT, and according to the domestic road conditions have been adjusted. The new transmission has a good prerequisite basis, but after all, is a new technology.