Why do the engines of motor buses have to be rear mounted?

In fact, the biggest advantage of the rear engine is that this type of vehicle has a small curb weight due to its compact powertrain, good maneuverability, and low vehicle curb weight. The interior layout of the car tends to be reasonable, the floor in the compartment is flat, and the engine is separated from the compartment, so the indoor vibration and noise are small, the temperature in the car is improved, the comfort is good, and the utilization rate of the compartment area is high; The axle load distribution is more reasonable, and the engine can be repaired outside the vehicle; In addition, a large baggage compartment can be formed under the floor.

However, its disadvantages are: the engine is moved to the back to make the cooling problem difficult to solve, the heat dissipation conditions are poor, it is easy to cause overheating, the cooling system is required to be higher, and the water tank is difficult to arrange. During the action, the negative pressure formed at the rear of the car and the dust raised by the wheels make the air intake environment deteriorate, the engine dust prevention is more difficult, the filtration effect and sealing requirements of the air intake system are higher, the rear axle is easy to overload, and the car has a tendency to oversteer when fully loaded; The engine is far away from the driver, and the control levers such as transmission, clutch, and accelerator should pass through the narrow bottom of the car, and are connected from the position of the driver at the front to the position of the rear engine, and the control mechanism is complex, and the control stability is poor; Difficulty in converting into vans and station wagons; It is not easy to judge the fault and abnormal noise according to the engine sound; The front of the occupants loses the engine as a "safety barrier", and the front end of the car should be reinforced to make the cost rise, and the engine noise is easy to transmit to the passengers, which affects the ride comfort, for this reason, restricts the development of this type of car.

However, for buses with sufficient space (such as Dongfeng buses), it can not only solve the above troubles, but also reduce the degree of exhaust gas entering the compartment, so this form is still more popular.

I'm happy.

The drive mode of the bus is rear-wheel drive, and if the drive shaft is too long, it will inevitably affect the drive structure.

Generally rear-mounted, but also front-mounted! Yutong ZK6115 is Considering the heat dissipation and appearance of the engine, the shape of Yutong ZK6115 is heavy in the front and light in the rear, which is ugly Look at the picture!

There are many reasons why the engine of the bus is rear-mounted, so let's briefly talk about the necessity of the rear engine of the bus.

The first reason is that the engine of the bus is designed to be rear-mounted to make room for the front of the car, reducing the height of the cockpit and thus reducing the driver's capacityBlind spotsAssuming that the engine of the bus is front-mounted, the bulky engine and its accessories will occupy a lot of the front position, so the driver's cabin will have to be raised. And we all know that the equivalent of a small car with a front-mounted engine.

There are many blind spots in buses, and the higher the position of the driver's compartment, the more blind spots there will be. If the engine of the bus is designed to be rear-mounted, it can free up a lot of space for the front of the car, so that the position of the cockpit can be lowered a lot, and the driver's blind spot will be reduced a lot.

The second reason is that buses are generally rear-drive, and the power loss will be high in transmission if the front engine is designed. Unlike family cars, which can be set up as front-wheel drive, buses generally have a larger load mass, so the demand for power is greater. If it is designed as a front-wheel drive, the front wheels are responsible for both driving and steering, which not only slows the vehicle but also damages the front wheels.

On the one hand, the design of rear-mounted rear-wheel drive reduces the burden on the front wheels, and on the other hand, the distance between the engine and the rear wheels is close, and the power loss in the process of transmission is smaller, and the power obtained is more sufficient.

The third reason is that the bottom layer of the bus is generally designed as a luggage compartment, if it is a front-mounted engine, the transmission mechanism will encroach on the position of the luggage compartment, making the luggage compartment space smaller. We all know that buses are generally double-decker designed, with the lower floor being the luggage compartment and the upper floor being the passenger cabin. If the engine of the bus is designed at the front of the car, it includes a transmission shaft more than ten meters long.

The transmission mechanism will encroach on a lot of space in the baggage compartment. Not only will this make the baggage compartment look unsightly, but the space in the baggage compartment will also be small.

Because the engine of the bus is designed to be rear-mounted, it can make room for the front of the car, reduce the height of the cockpit, and thus reduce the driver's blind spot.

Because the rear-mounted engine can produce more thrust, such a car powertrain is more compact, maneuverable, faster, and can save some space, can be placed in a few more positions, and is also good at heat dissipation.

That's because that's the only way to have more power and make the car engine less loud.

The engines of buses are generally rear-mounted, why is that? Trucks and buses are relatively large vehicles that we can see on weekdays, but they are both large vehicles. Many bus engines.

Located at the rear of the vehicle, while the truck engine is located at the front of the vehicle. What is the reason? Today, we continue to increase our knowledge that cars have no practical use. In the early days, buses and trucks shared a chassis and were front-engined.

In the past, trucks and buses used the same chassis. This chassis is called a "straight-through belt chassis". The engine is located in the front, and the power passes through the propeller shaft.

Transfer to the rear-wheel vehicle. Loaded onto the truck.

The shell is the truck, and the shell of the bus is loaded.

It's a bus. The wooden passenger car shell is directly applied to the truck chassis, and the passenger car adopts the form of rear traction, which is aimed at saving the transmission shaft, increasing the space, and reducing the chassis height; For large vans.

Isn't it nice to use the front engine? If the heavy weight is concentrated in the rear of the vehicle, the engine is placed in the rear of the vehicle, and the counterweight at the front of the vehicle is not sufficient (the head and tail are lighter), the towing capacity of the large van will be greatly reduced, I mean, when it starts to collapse, it will increase frequently! Therefore, if the engine is located behind the head of the heavy goods vehicle, there is no need to consider feasibility.

The total counterweight may outright reject the rear and rear drive modules; Trucks and buses opt for the rear wheel because they can generate more thrust, and these vehicles generally have two rear wheels that have more friction with the ground. The reason for leaving the front wheel disc is that the front wheel must rotate, and it is a single-wheeled shirt with high tires, in fact, the biggest advantage of the rear engine is that the engine is compact, the maneuverability is good, the curb quality is low, the vehicle layout tends to be reasonable, the floor is flat, the engine is separated from the vehicle, so the internal vibration and noise are small, the temperature in the car is improved, the comfort is good, and the speed of use in the car area is high; The axle load distribution is reasonable, and the engine can be repaired outside the wheel; In addition, a large trunk can be formed under the floor.

The non-load-bearing body is a common chassis for buses and trucks. It is a frame chassis made of a large number of ordinary to ultra-high-strength steels. Ordinary family scooters do not have such a chassis.

It is a frame welded with steel plates; When this frame is placed on a non-load-bearing chassis, it becomes an off-road vehicle, a pickup truck front mess, a bus, and various types of trucks. The car is in the form of rear rear drive. The aim is to save the propeller shaft, increase space and reduce the height of the chassis.

If the engine is placed behind the head of a heavy truck, there is no need to consider feasibility, and the overall counterweight can directly negate the form of rear-wheel drive and rear-wheel drive; In contrast, passenger cars have longer bodies, and the seats and trunks at the bottom are arranged from top to bottom, so the overall weight distribution of the passenger car should be even, rather than the weight of the truck in the rear. Passenger cars do not need to be heavily loaded. Even if the number of passengers is 50, the average mass is 50 kilograms, that is, 2500 kilograms; These weights and engines are concentrated at the rear of the vehicle, which has a significant impact on the ratio of weight to the front and rear of the body.

The layout of the seats is always balanced, and there are not many rear seats in the car; Buses usually only need to arrange seats at the back of the bus and leave aisles in the middle and front positions to accommodate more standing space. It should be well understood that trucks use mid-rear drive. First, trucks mainly transport goods in the back of the truck, and it is not possible to ensure that the position of cargo density (distinguishing dumped goods from heavy goods) is consistent; Then, if the heavy engine and gearbox are placed in the rear of the car, and the load is still pressed on the rear of the car, I am concerned that the front of the car may tilt when climbing hills.

Large trucks want to control manufacturing costs, and mid-rear drive is also the final choice. The air conditioning and heating of the passenger car can be installed at the rear to supply air directly to the car. If the truck engine is set in the rear, separate ducts must be used to deliver air conditioning and warm air to the front of the car.

It's scary to think about. The volume of the engine-transmission is very large. If placed in the rear of the car, it should be higher than the chassis and should not fit the cargo box.

On top of that, the rear of the bus engine is because people have this need, and the chassis of the big trucks has always been perfect. There is no new design that places the engine in the rear of the car.

The rear engine of the bus is to facilitate the passengers to get on and off the bus, and at the same time reduce the vibration of the bus and improve the comfort of passengers.

Because this can improve the disassembly power prudently, and it can also play a better role, but also can reduce the pressure on the engine of the wide key on the truck.

Because the power system of the bus should not be particularly high, and the large truck needs to pull goods, so its power system should be very strong.

Introduction: In daily life, we often see some large cars, large trucks and buses are also large vehicles. But the position of their engines is different, with and Shen buses generally have the engine rear, while large trucks have the engine front, what is the reason? <>

The reason for the rear engine of the car is to facilitate the entry and exit of passengers, and there will be a rotating shaft under the car, and if the engine is placed in front, the floor may be raised, which will make the temperature in the bus very low. In addition, if the engine of the bus is forward, it may affect the use of space. It will also cause the noise and smell of the engine to easily spread to the cabin, which will affect the health of passengers.

Moreover, if the carriage is too high, it is not conducive to children and the elderly getting on and off the train. At the same time, when the engine of the bus is rear-mounted, it can also improve safety. Because when it is front-loaded, it may cause the driver to have a relatively large blind spot when driving.

Because trucks are heavier, the engine front phone converts power into propulsion. The rear wheels are mainly responsible for the load, and there is not much room for the engine in the back. At the same time, the front engine will make the driving force of the car better, and the acceleration and climbing ability can be strengthened.

At the same time, the front engine will also make the mechanical rotation efficiency of the delivery vehicle high. The front engine improves the comfort of the rear seats, which makes it easier for the driver to drive the car. Moreover, the engine of the large truck is front-loaded, the safety performance is more reliable, and this technology is more mature.

Front-engined trucks also have some collisions that reduce injuries to drivers. <>

The engine is a device that can provide power to the car, it is equivalent to the heart of the car, and can carry out energy conversion. Through the engine, the heat energy of gasoline or diesel can be burned in the cylinder to push the piston to do work, and it can be converted into mechanical energy. At the same time, it also determines the power of the car, as well as the performance of stability and environmental protection.

According to the different powers, car engines can be divided into diesel engines, gasoline engines, electric vehicle motors, etc. According to the working mode of the air intake system, it can be divided into vortex pressurized type, mechanical pressurized type, etc., and can also be classified according to different cooling methods.

Because the bus is generally oriented to passengers, the front engine is convenient for passengers to get off, and it is also conducive to regulating the temperature in winter and summer. And the big truck doesn't have to take the rent test, and Min Spine has to worry about how much it hurts to travel.

The performance of large trucks and buses is not the same, and the rear engine of Xunxun shouting bus is to provide overall kinetic energy. The front of the large truck is able to provide greater power to the cockpit.

If the engine of the bus is rear-mounted, the noise will not affect the passengers, and it is also convenient for Peizhi to place the luggage Hongzhongyan, and the engine of the large truck is front-mounted, which can better provide power.

The rear engine of the bus is to facilitate the passengers to get on and off the bus, and the front engine of the large truck is because the truck is heavier.

First of all, passenger carsLarge rear engine greatlyReduced engine vibration and noise。The front and rear counterweights of the passenger car are larger than the front, and the two-wheel design will produce greater friction and thrust; If front-wheel drive traction is insufficient; The front part carries steering and other components, and the space and technology are more complex; The interior space of the front of the bus is reduced, which is more beautiful and smooth, and the space of the bus can be used more effectively without occupying the space of the drive shaft.

Secondly, since the engine is placed in the rear, there is no need to occupy front space。As a result, the chassis layout at the front is more flexible, and the driving position can be set to a lower position as needed, which can greatly reduce the driver's blind spots. Some long-distance luxury buses are even lower than some family cars.

Coupled with the flat body, even behemoths can have a very good field of view.

Then there is the structure and nature of the large wagon, the engine of which simply cannot be placed in the rear。Passenger car air conditioning heater can be set in the rear, directly to the compartment air supply, if the engine of the large truck is installed in the rear, the air conditioning warmer must be delivered to the compartment. The front of the locomotive passes through a separate pipe.

The engine gearbox is bulky, and if it is placed in the rear of the car, it will be higher than the chassis, and the cargo box will not fit.

On top of that, the bus engine is rear-mounted because people have this demand, and the chassis of the big truck is already perfect, and there is no new design that needs to put the engine in the rear. Heat dissipation from the rear engine is a big problem. The radiator of the front engine is located in the front of the car.

Airflow can easily help the engine cool down while driving, with little to no need for a cooling fan. However, rear-engined passenger cars have little air flow into the engine compartment while driving, so heat dissipation is an issue. Many rear-engined passenger cars have fire extinguishing bombs in many places in the engine compartment.

If the engine spontaneously combusts, the fire extinguishing bomb will automatically explode to extinguish the fire. As a result, we often see some buses running with their hoods open in the summer, all for better heat dissipation.