What are the main parts of the high pressure fuel injection system?

Hello, that's a good question! The diesel engine fuel supply system is composed of a diesel tank, a fuel pump, a low-pressure oil pipe, a diesel filter, a fuel injection pump, a high-pressure oil pipe, an injector and an oil return pipe. The diesel fuel is sucked out from the diesel tank by the fuel pump, and a certain pressure is generated, and the impurities are filtered out by the diesel filter and then enters the fuel injection pump, and the fuel injection pump increases the oil pressure of the low-pressure oil, and the high-pressure oil is sprayed into the combustion chamber through the high-pressure oil pipe and the injector.

Due to the large amount of fuel supplied by the fuel pump, part of the excess diesel oil flows back to the fuel pump or diesel tank through the injector return pipe, and the other part flows back to the diesel tank through the pressure limiting valve and the return pipe. Look!

The fuel injection system is mainly composed of low-pressure oil circuit, high-pressure oil circuit, electronic control unit and various sensors.

High pressure oil pumps, high pressure oil rails, high pressure injectors, and high pressure oil pipes!

There are two kinds of BAI control fuel injection systems: 1. The DU injection pump of the mechanical fuel injection system is maintained, and the electric control ZHI governor replaces the mechanical governor to control the oil quantity control rod (in-line pump) or control the sliding sleeve (distribution pump), and the fuel injection volume is controlled by position. For example, the RED series governor of the in-line pump and the VP37 of the distribution pump series.

This electronic control method is commonly known as positional control. 2. Cancel the oil quantity control mechanism of all mechanical structures, only retain the mechanism of mechanical oil pressure and flow, and the oil quantity control is controlled by the opening and closing time of the solenoid valve. Such as electronically controlled single pump, electronically controlled pump nozzle, high-pressure common rail system.

This type of electronic control is commonly known as temporal control.

According to the different injection parts, it can be divided into two types: in-cylinder injection and out-of-cylinder injection.

In-cylinder injection is the injection of gasoline directly into the cylinder through an injector mounted on the cylinder head. The off-cylinder injection system is to install the injector on the intake pipe or intake manifold, and the off-cylinder injection system is divided into inlet pipe injection and inlet channel injection.

Fuel injection systems include: fuel tank, fuel pump, fuel filter, fuel supply rack (fuel distributor, fuel distribution pipe), pulse pressure reducer (fuel pulsation damper), fuel injector, oil pressure regulator, etc.

1.Oil Pump: A

The function of the check valve: after the oil pump is stopped, a certain residual pressure is maintained in the system for the next landing. b.

Use of Safety Valves: Also known as pressure limiting valves or oil spill valves. When the oil pressure of the fuel system exceeds a certain value, the fuel system will open and drain the oil pressure to prevent damage to the oil pump and oil pipe.

2.Oil Pressure Regulator: It is used to regulate the oil pressure of the fuel system. When the vacuum acts on the ball valve, the oil pressure regulator works and connects the return line.

3.Injector AFeatures:

According to the ECU signal command, the valve pin is opened, and a certain amount of well-atomized fuel is injected into the cylinder. b.Location:

Located at the intake manifold and fixed to the oil supply rack. c.Measure.

Measuring the injector signal: after the wire harness is broken. Plug in the plug, start the engine or after starting the vehicle, measure the signal pins of the plug with a test light.

The test light should be flashing. If it is turned on or off normally, check the main control signal or clean. When the fuel injection port is carbon deposited or the internal is blocked, the fuel injection volume is too small and the mixture is too thin; If the nozzle of the fuel injector is worn, it will lead to good atomization and excessive fuel injection, which will make the mixture too thick and the exhaust pipe emit black smoke.

If the nozzle is not closed tightly, it will cause the nozzle to leak oil and make the mixture too thick. If the situation is severe, it is easy to drown the spark plug.

4.Connecting the oil pressure gauge: In general, there is a diagnostic interface on the oil supply line. For those that don't, we connect them to the inlet pipe in the form of a three-way valve.

To sum up, the fuel injection system includes: fuel tank, fuel pump, fuel filter, fuel supply rack (fuel distributor, fuel distribution pipe), pulse pressure reducer (fuel pulsation damper), fuel injector, oil pressure regulator, etc. The function of the fuel injection system is to provide a certain quality, clean and well-atomized gasoline for the electronically controlled engine to ensure that it meets the needs of various working conditions, and the theoretical fuel ratio is: 1.

The components of the gasoline injection system are mainly composed of three parts: air intake system, fuel supply system and electronic control system. The diagram below shows the composition of an electronically controlled fuel injection system. The air system of the mass flow injection system consists of an air filter, an air flow meter, a throttle body, an air valve and a pressure stabilizing box.

The electronically controlled fuel injection system is composed of three parts: air supply system (gas circuit), fuel supply system (oil circuit) and control system (circuit). The full name of electronically controlled fuel injection system is electronically controlled fuel injection system, commonly known as gasoline injection.

The electronically controlled fuel injection system is a system in which the engine control unit ECU controls the fuel injection time, pulse width and injection law of the gasoline engine.

Sensor, ECU and Actuator

1. Sensor: can feel the measured information, and can transform the felt information into electrical signals or other required forms of information output according to a certain law, so as to meet the requirements of information transmission, processing, storage, display, recording and control.

2. Electric control:

1) Take an instruction from memory and indicate where the next instruction is in memory.

2) Decode or test the instructions, and generate the corresponding operation control signal in order to start the specified action.

3) Command and control the direction of data flow between CPU, memory, and input and output devices.

3. Actuator: The control signal sent by the controller changes the size of the controlled medium, so as to maintain the controlled variable at the required value or within a certain range.

The air intake system, fuel supply system, electronic control system, which are the basic components, are very simple to learn and arrange.

The gasoline engine is composed of an out-of-cylinder injection engine gas path.

Answer: 1. Bore injector 1Bore Injector Bore injector is used on direct injection combustion chamber diesel engines.

The head of the injector of the hole injector is processed with one or more nozzle holes, the one with one nozzle hole is called a single-hole injector, the one with two nozzles is called a double-hole injector, and the one with more than 3 nozzle holes is called a multi-hole injector.

There are three types: bore type, shaft pin type, and low inertia.

It is divided into two ways: multi-point injection and single-point injection.

1. According to the location of fuel injection.

1. In-cylinder injection - gasoline engine for lean combustion.

2. Inlet tract injection.

A: Spray in front of the intake valve – only for MPI

B: Spray above the throttle – only for SPI

Second, according to the way of fuel injection.

1. Simultaneous injection - each cylinder injector injectors inject fuel at the same time.

2. Group injection - each cylinder injector is divided into several groups, and each group takes turns to inject alternately.

3. Sequential injection - injection according to the working order of the engine.

3. According to the air flow measurement method.

1. Mass flow type.

2. Velocity density type.

3. Throttling speed type.

Electronically controlled engine fuel injection can be divided into 2 categories.

The first type is EFI electronically controlled sequential fuel injection, which is the usual injection method adopted in automobiles today.

The second category is single-point injection, which is generally on the old Hongqi or Jinbei engine, and Chery Qiyun is a car.

Single-point injection, which is more common, has now been phased out due to the lack of EFI injection for fuel efficiency.

The basic form of automatic control system There are two basic forms of automatic control system, namely open-loop control and closed-loop control.

1. Open-loop control is the simplest control method, which is characterized by the fact that there is only positive control between the controller and the controlled object and no feedback control, that is, the output of the system has no effect on the control quantity.

2. The characteristics of closed-loop control are: between the controller and the controlled object, there is not only a positive control effect, but also a feedback control effect, that is, the output of the system has a direct impact on the control quantity. The basic functions of the closed-loop control system are signal propagation, processing and comparison.

When the engine is running in a cold state or under high loads, the engine ECU performs an "open-loop" control to supply a thick air-fuel mixture to ensure engine performance. In addition, when the engine is running in a hot state or under normal load, the engine ECU uses the oxygen sensor signal to control the air-fuel mixture for "closed-loop" control, so as to obtain a theoretical air-fuel mixture ratio. This mixing ratio through a three-way catalytic purifier will provide the cleanest emissions.

It is divided into single-point EFI and multi-point cylinder-by-cylinder injection.

The role of the injector is:

1. Increase the oil pressure (constant pressure): increase the injection pressure to 10MPa 20MPa.

2. Control the injection time (timing): inject and stop the injection according to the specified time.

3. Control the amount of fuel injected (quantitative): according to the working condition of the diesel engine, change the amount of fuel injected to adjust the speed and power of the diesel engine.

The injector receives the injection pulse signal from the ECU to precisely control the amount of fuel injected. The injector is a precision device with very high processing accuracy, which requires a wide dynamic flow range, strong anti-clogging and anti-pollution ability, and good atomization performance.

The oil supply pressure, the oil supply flow, the fuel injection pulse width of the injector. Three aspects determine the amount of fuel injected.

The fuel supply pressure is determined by the fuel pump.

The flow of fuel is determined by the patency of the pipes, fuel filters and injectors when they are opened.

The injection pulse width is determined by the engine computer mainly based on the air flow meter (or intake pressure sensor), engine speed, and throttle position sensor. Water temperature sensor, oxygen sensor, inlet air temperature sensor play the role of correcting the pulse width of the fuel injection. The water temperature correction is the main correction.

It is mainly controlled by injector, fuel rail, oil inlet pipe, oil return pipe, oil pressure sensor, speed sensor, throttle position sensor, and ECU.

According to different working conditions, different speeds, different throttle positions, the amount of fuel injection is controlled.

New energy vehicles refer to the use of unconventional vehicle fuel as the power (or the use of conventional vehicle fuel, the use of new on-board power units), the integration of vehicle power control and drive advanced technology, the formation of advanced technical principles, with new technologies, new structure of the car. The main difference is from the internal combustion engine vehicles fueled by gasoline and diesel fuel.

New energy vehicles include pure electric vehicles, extended-range electric vehicles, hybrid electric vehicles, fuel cell electric vehicles, hydrogen-powered vehicles, and other new energy vehicles.

The following is an introduction to several mainstream types of new energy vehicles in the market:

1. New energy includes hybrid vehicles: hybrid vehicles that use fuel and electricity as driving raw materials. At present, major brands basically have such models, such as: Mercedes-Benz S400, BMW 5 Series, etc., these hybrid vehicles will be marked with the word hybrid.

2. Pure electric vehicle: This car is completely detached from fuel and completely relies on electricity as the driving raw material for hybrid.

3. Fuel cell vehicle: This car is also a battery car, which is a hydrogen-oxygen hybrid fuel cell, you can quickly fill the battery fuel without waiting for charging.

4. Hydrogen-powered vehicles: This car is also completely detached from fuel and uses hydrogen energy to replace fuel.

There are other new energy vehicles, such as: dual-fuel vehicles, natural gas vehicles, etc.

It mainly controls the idle speed and the corresponding throttle.

The amount of fuel injected mainly refers to the intake air temperature, water temperature, detonation degree, and throttle opening.

The fuel injector is an important part of the engine's fuel system, and its main function is to inject fuel into the combustion chamber of the engine at a certain pressure to achieve combustion and power output. The injector is composed of the following main parts:

1.Fuel injection pump: responsible for pumping fuel from the fuel tank and compressing it to a certain pressure to supply the fuel injector.

2.Fuel injector: responsible for injecting high-pressure fuel into the combustion chamber for combustion and power output. The amount and timing of the injector are controlled by the controller to achieve precise fuel injection.

3.Sensor: Responsible for monitoring the working status of the engine, such as engine speed, load, air intake, etc., to provide feedback signals to the controller to achieve accurate control of fuel injection volume.

4.Controller: Responsible for controlling the amount and time of fuel injection at the injector according to the feedback signal provided by the sensor to achieve accurate fuel injection.

The above is the main component of the injector and its function, and their coordinated work can make the engine achieve high efficiency, low emission, low fuel consumption and slip under various working conditions.