Chassis role is to force acceptance of the engine, so that rotation of the wheels, and ensure the car according to the driver's manipulation of normal driving. Chassis includes transmission, driving system, Honda Civic FG1 Coilover steering system and brake system four parts, generally, these four systems are also referred to as the drive train, driving system, steering system and brake system.

Drive Train:

Driveline We should not feel strange. We all know that clutch and the transmission of it, they are an important component of the drive train inside, the driver and they are very much playing dealings (after the steering wheel), a trip to the car ran down, who can remember in the end eliminate themselves step How much lower clutch, gear change how many times?

From the transmission power, the transmission lines are connected to the engine and the wheels ties, including the clutch, transmission, drive shaft, drive bridges. Automotive drivetrain and transmission medium in accordance with the structure can be divided into mechanical, hydraulic mechanical, Honda Civic FG2 Coilover hydrostatic type, power type, and so four types, for the vast majority of vehicles, the most common is the purpose of mechanical and hydraulic mechanical Both. There are a variety of drivetrain arrangement, car FF common way (ie, front-engine, front-wheel drive); trucks, buses and a small part of most common limousine FR mode (ie, front-engine, rear-wheel drive); Deluxe RR Passenger commonly used way (ie hair dryer machine rear, rear-wheel drive); off-road vehicles with nWD fraction (ie, all-wheel drive to persuade, n represents the number of wheels); and the way the car is generally used MR (ie mid-engine, rear-wheel drive). In addition, the engine is taken transverse or longitudinal arrangement will also affect the drivetrain.

The primary task of the drive train and engine is coordinating work to ensure the car can travel at normal conditions of use do not ask. And has good power and fuel economy. Out of this, no matter what type of transmission system, at least we should have to BU four basic functions:

1. Deceleration and speed change

We know that only when acting on the driving wheel traction is sufficient to overcome the resistance of the outside of the car, the car can only start-up and normal driving. We wish to ordinary Santana Case, Santana weight 1070kg, engine displacement of 1.8 liters, maximum torque of 150N · m / 3100rpm, maximum power 72kw / 5200rpm, wheel size is 195 / 60R14. It is assumed that at the level of dry cement road to 90km / h speed constant speed, then, it is subjected to the resistance can be calculated using the simplified formula: F = mgf ten CdAua2 / 21.15 (m is the car's weight, front We said to 1070kg; g is the gravitational acceleration, which is 9.8m / s2; f is the tire rolling resistance coefficient, for cement pavement, f = 0.014x (1 ten ua2 / 19440); Cd is air resistance coefficient, about 0.32; A for the automotive frontal area, Santana is 1.89m2; ua vehicle speed, we have set at 90km / h), the calculated results for 440N. Next, let us calculate its driving force, the driving force is calculated as Ft = Ttqigi0nT / r (Ttq engine torque, in this case the maximum torque of 150N · m / 3100rpm; ig and i0 are transmission ratio and primary reducer transmission ratio; nT mechanical efficiency drive train; r is the radius of the tire, r = 14x0.0251 ten 0.195x60% = 0.47m), if the direct effect of the engine torque to the drive wheels (ie no engine power After transmission system directly acting on the wheel, this time, ig and i. are 1, nT 1). It is possible to obtain maximum traction wheels about 319N. Obviously, traction yet with big resistance, in this case the car is unable to start or continue running, it will gradually slow down until it stops. At the same time, we can also look at, if the engine connected directly to the tire, when the engine rotation speed of 5000rpm operation, according to ua = 0.377r · n / igi. (Parameters as above, n is the engine speed), the speed will hit a staggering 886km / h, this speed is not practical, it is impossible to achieve (because this time the resistance is very large, traction and small car there is no way forward ). In order to resolve these contradictions, we must have the driveline requires deceleration by twisting effect (the reduction effect), while the main gear unit is playing such a role.

Also, the car use conditions (such as the quality of the actual load, road grade, road conditions, and the width and curvature, Honda Civic FG1 Shock Absorber road traffic conditions permitted speed, etc.) due to a number of factors which are constantly changing, which requires car traction and speed have a considerable range. On the other hand, since the engine torque over the entire speed range changes little, power and fuel consumption curves is quite large, which makes the engine speed range to maintain high power with low fuel consumption (we can call it a favorable speed range) is very narrow, in order to keep the engine speed within a favorable range, the gear ratio of the transmission system needs to vary within a certain range. So, from this perspective, the driveline must also have the role that speed, the transmission also emerged.