common rail denso

BENEFITCommon Rail SystemCommon Rail System

The features greatly reduce visible smoke, particulate matter and NOx while minimizing engine noise.

DENSO’s second-generation 1,800-bar common rail for cleaner and quieter diesel engineDENSO’s second-generation 1,800-bar common rail for cleaner and quieter diesel engine

Innovative technologies greatly reduce diesel’s impact on the environment.1. Up to 1,800-bar injection pressure2. Up to five times multiple injection per cylinder

BENEFIT

Cleaning up diesel exhaust gas Minimizing engine noiseHighly precise multiple injection creates combustion to reduce NOx emission and combustion noise.

Diesel fuel is injected into the combustion chamber at ultra high pressures of up to 1,800 bar to ensure more complete combustion for cleaner exhaust gas.

Common Rail SystemCommon Rail System



BENEFIT

Single Injection(Conventional)

Pilot Injection(First-Generation Common Rail)

Multiple Injection(Five Times)




BENEFIT

Single InjectionSingle Injection

Pilot Injection

Multiple Injection

Condition・Passenger Car・Engine: 2L / 4cyl・Turbo Direct Injection・Noise at Idlingtime



BENEFIT

-3ｄB

Single Injection

Pilot Injection

Multiple Injection

time

Condition・Passenger Car・Engine: 2L / 4cyl・Turbo Direct Injection・Noise at Idling



Pilot Injection (Two Times)

BENEFIT

-4ｄB

Multiple Injection (Five Times)Single Injection

Pilot InjectionMultipleInjection

time

Condition・Passenger Car・Engine: 2L / 4cyl・Turbo Direct Injection・Noise at Idling



TECHNOLOGY

High pressure capacity technology

Magnetic valve technology

High pressure capacity technology

Magnetic valve technology

ECU technologySensor technologyECU technology

Sensor technology

Common rail technology

Common rail technology

TECHNOLOGY Common Rail System

EGR Valve

DPF

Diesel engines have the advantages of good fuel efficiency and low CO2 emissions. Therefore, DENSO developed a diesel engine management system to further clean up emissions while improving fuel efficiency. This system is a product of various forms of advanced technology. Among them is the common rail system employed in the fuel injection.

1,800 bar injection pressure is equivalent to the water pressure of a depth of 18,000 meters deeper than the Mariana Trench, the world’s deepest ocean bottom. High response injectors by electronic control feature the highly accurate multiple injections (five times). As a result, particulate matter and NOx are markedly reduced, while improvements in fuel efficiency and torque are achieved. Plus, engine noise and vibration are also reduced.



Diesel Engine Management System

TECHNOLOGY

TECHNOLOGY 1 Supply Pump

TECHNOLOGY 2 Common Rail

From Supply Pump

To Injector

Pressure Sensor Pressure Limiter

To Injector

Feed Pump

Connecting Pipe

Cam Shaft

Plunger

Cam Ring

Suction Control Valve Eccentric Cam

To Rail

Housing

Supply Pump

Common Rail

The first-generation supply pump could generate pressures of up to 1,450 bar, which represented the mechanical limits of the inner cam design. However, to achieve pressures above this, DENSO developed revolutionary new coating and machining technologies, and by the second-generation design, changed to an outer cam design in the supply pump to achieve pressures up to 1,800.

In order to w ithstand 1,800-bar pressure the rail must be w ithout any clearance or machining error. In response, DENSO developed a special material that contains fewer compounds, while exhibiting high purity and high hardness properties to enable ultra high-precision machining. Thus, it is possible to create engine components that can w ithstand pressures up to 1,800 bar for use in the common rail system.



TECHNOLOGY

TECHNOLOGY 3 Solenoid Injector

160MPaQpilot :2mm3/st , Qpre: 2mm3/st , Qmain:80mm3/st , Qafter:5mm3/st , Qpost :2mm3/st ,

1.0ms

Drive Current(A)

Valve Lift(μm)

From Rail(high pressure)

Command Piston

Nozzle

Solenoid Valve

Injection Rate(mm /ms)3

Injector (up to 5 times injection a cylinder)Compared w ith its first-generation injector (1,450 bar, two-times injection) DENSO developed higher-response solenoid actuator and high-pressure injector design. The second-generation injector is able to inject up to 1,800 bar pressure and multiple injection, w ith timing intervals of 4/10,000 seconds during which a maximum of five injections takes place. As a result, exhaust gas is cleaner while noise is minimized.

In injection control systems, advanced piezoelectric components are employed because of their high speed operation capability. But DENSO was successful in developing conventional solenoids that operate in 0.2 millisecond units.

time

time

time



common rail denso

Documents