How many gears are there at the top of the truck?
Large trucks, 14. Forward 6*2=12, reverse 1*2=2. Actually, this car has two stalls. One gear has 6 forwards, one back, and the 21 is up and down.
Especially heavy trucks, because the speed of the diesel engine itself is not high, mainly by a number of stalls to adjust speed, if the gear is too small, it is not easy to open. Suppose a truck has only 5 gears, the 5 gear ratio is 10, and the 4 gear ratio is 12. If full of goods, the transmission ratio is 10, the engine may transfer to a tire torque is not fixed, but with 12 speed ratio, may not necessary too, so the cost of oil, if inserted into a file between the two gear transmission ratio of 11, perhaps just fine.The number of stalls of the car gear will be slightly complicated, but you did not imagine in so much trouble, it is the same location has two stalls, 1 stalls to pull up, there are 2 files, one known as high - grade, 16 forward, in fact, as long as the mobile transmission 8 A position. In addition, the number of stalls in the car is allowed to leapfrog, stalls, allowing high-grade start, because it is 1, 2, and 3 gear shift ratio is actually very close.
Take the 5 gear car as an example, the gear ratio of the 1 gears is 3 times of the 5 gear, and the 4 gear is about 1.2 times of the 5 gear. With more gears, the gearshift range is wider than the optional range. The speed of the engine is very high, in thousands of, but the torque is not large, only about 200N.m. Such a small torque acts directly on the car body and is obviously unable to pull. Therefore, through the gear combination to achieve different speed ratio, torque amplification, while the speed decreased accordingly. Each gear transmission ratio between different, such as file total transmission ratio hypothesis 5 is 10, which is the torque of the engine 10 times magnification, and the rotation speed is reduced to 1/10, such as the engine speed of 3000 rpm, so the tire 5 stall speed only 300 rpm and torque is expanded to 10 times.
The car stalls, each stall speed smaller than the difference, will shift more smoothly, and can be chosen according to different speed and load, the weight of the appropriate gear.
While the 5 gear car is generally prohibited leapfrog upshift, no high-grade start, because 5 cars, 1 general gear strength is 1.5 times of 2 stalls, is about 1.7 times the 3 speed difference is very big, 2, 3 started very hurt clutch, 1 started directly after the 3 grade, master not good, easy to gear. The 16 stalls of the car, it is likely that the strength of the 1 stalls only 3 times 1.2 times, empty flat ground can start in 3 stalls, full car flat 2 stalls start, full car uphill only 1 stalls start. But after starting, the speed adds up to be able completely to skip the grade to increase the file, from 1 files to 16 gears, does not mean must change 15 files, perhaps 8 times is enough.
