Bơm ECD-V - P - Types of Systems in ECD-V Series

Tất cả tài liệu về bơm ECD-V (tài liệu đào tạo của Denso ECD): -Composition and Construction of ECD-V3 Pump System -Determining the Injection Timing -ECD-V Series -ECD-V4 Outline -ntake Restriction Control -Outline of Injection Ti

9SERVICE TECH Vol.465 03-4 The previous session covered the changes in the environment surrounding the diesel engine and described the ECDsystem (ECD-V series) and the common-rail system. This session describes the types of systems in the ECD-V seriesand their system configurations. Although the injection pump has the same basic construction as the distribution type pump, the ECD-V3 includesthe parts listed below due to the adoption of electronic control.• Solenoid spill valve (SPV) . . . . . . . . . . . . . . . . An actuator that controls the injection volume• NE sensor (NE) . . . . . . . . . . . . . . . . . . . . . . . . A sensor that detects the cam position of the pump• Fuel temperature sensor (THF) . . . . . . . . . . . . A sensor that detects the temperature of the fuel• Correction resistor or ROM . . . . . . . . . . . . . . . A part that corrects the injection volume and injection timing• Timing control valve (TCV). . . . . . . . . . . . . . . . An actuator that controls the injection timing The V1 is the first of the ECD-V series, which appearedin 1982. The V3, a swirl-chamber type diesel injectionsystem, appeared in 1985. The V3, which adopted a solenoid spill valve to controlfuel injection, enabled the control of the injection volumeon a cylinder-by-cylinder basis. Depending on the type of final injection volumecorrection and the solenoid spill valve that are used,three types of ECD-V3 are available: ECD-V3, ECD-V3(ROM), and ECD-V3 direct-acting valve. The V4 direct-injection diesel fuel injection system forsmall trucks and SUVs appeared in 1998. The V4 system, which uses an inner cam pumping mechanism, enables high-pressure injection at 1,300 bars. The V5 direct-injection diesel fuel injection system for passenger vehicles appeared at about the same time. TheV5 system uses pilot injection to reduce the combustion noise of the engine.11Types of Systems in ECD-V Series1-1 ECD-V Series1-2 Injection Pump for ECD-V3 10SERVICE TECH Vol.465 03-4 The ECD-V4, which is based on the ECD-V3, is an electronically controlled distribution type pump that hasadopted a completely new construction. The combustion performance of the engine with the ECD-V4 has beenimproved (by atomizing the fuel into finer particles and optimizing the rise rate of the injection pressure), andproviding the injection volume and injection timing with a higher level of precision and freedom. With respect to themajor changes that have been made from the ECD-V3, an inner cam mechanism, a highly responsive solenoidspill valve and EDU, and a correction ROM have been adopted. The ECD-V5, which is based on the ECD-V3, is a distribution type, electronically controlled fuel injection pump thatoffers higher injection performance and functionality. It provides pilot injection to reduce the combustion noise of theengine.1-3 Injection Pump for ECD-V41-4 Injection Pump for ECD-V5 SERVICE TECH Vol.465 03-411 The configuration of the ECD-V series system can be broadly classified into the following three systems: Intakeair system, Fuel system, and Control system. Intake air system . .This system, which draws the air that is necessary for combustion, consists of the areasfrom the air cleaner to the intake manifold. Fuel system . . . . . .This system, which injects the fuel that is necessary for combustion into the cylinders,consists of the areas from the fuel tank to the injection pump and the nozzles. Control system . . . .This system, which controls the fuel injection volume and injection timing, consists ofsensors (detectors), computers, and actuators. After being filtered through the air cleaner, the intake air travels through the turbocharger and the venturi, passesthrough the intake manifold, and enters the cylinders. The venturi consists of a "main valve" and a "sub valve". The main valve opens and closes in unison with theaccelerator pedal to draw the amount of air that is necessary for driving. The sub valve, which is located parallel to the main valve, is opened and closed by the diaphragm in order torestrict the intake air volume in accordance with the conditions of the engine.  The fuel from the fuel tank travels to the fuel filter & sedimenter where it is filtered and its moisture is removed.Then, it is drawn into the injection pump. As the fuel fills the injection pump, it lubricates and cools the moving parts in the injection pump. After the fuel ispressurized, it is injected into the engine cylinder by the injection nozzle. The excess fuel travels from the overflowvalve to the return pipe and returns to the fuel tank.22Outline of System Configuration12 31232-1 Outline of Intake Air System2-2 Outline of Fuel System 12SERVICE TECH Vol.465 03-4 The engine ECU uses various types of sensors to detect the engine speed, accelerator position, and switch signals.These pieces of information are used for the engine ECU to determine the operating conditions of the engine and thedriving conditions. Then, the engine ECU calculates the fuel injection volume and the injection timing that arenecessary for operating the engine in an optimal state, and actuates the valves. The control system can be broadly classified by their electrical components into the following three systems: Sensor system, ECU, and Actuator system. Sensor system . . . .Detects the engine conditions and driving conditions and converts them into electricalsignals. ECU . . . . . . . . . . . .Performs calculations based on the signals received from various sensors and sendssignals to the actuators in order to operate the engine in an optimal condition. Actuator system . . .Operates in accordance with the control signals received from the engine ECU.2-3 Outline of Control System1 2 3123 . system uses pilot injection to reduce the combustion noise of the engine.1 1Types of Systems in ECD-V Series 1-1 ECD-V Series 1-2 Injection Pump for ECD-V3 10SERVICE. provides pilot injection to reduce the combustion noise of theengine. 1-3 Injection Pump for ECD-V4 1-4 Injection Pump for ECD-V5 SERVICE TECH Vol.465 0 3-4 11 The