KR101440174B1

KR101440174B1 - Multi Fuel Inection Apparatus of Diesel Engine

Info

Publication number: KR101440174B1
Application number: KR1020100036065A
Authority: KR
Inventors: 김주태; 김응성; 박득진; 김종석; 허광철; 박정현; 정강윤; 하은; 노범용
Original assignee: 현대중공업 주식회사
Priority date: 2010-04-19
Filing date: 2010-04-19
Publication date: 2014-09-17
Also published as: WO2011132864A3; WO2011132864A2; KR20110116576A

Abstract

The present invention relates to a multi-fuel injection device for a diesel engine, and has a plurality of plungers provided in a fuel pump for injecting fuel so as to have different injection patterns, thereby achieving complete combustion.
The present invention relates to a fuel injection device for a diesel engine, comprising a fuel injection pump for injecting fuel and injecting it into a combustion chamber of each cylinder through an injector,
The fuel injection pump includes: a housing; A main plunger for injecting the main fuel introduced through the main fuel inlet into the housing through the main fuel outlet when the housing is lifted and lowered; The sub fuel is sucked through the sub fuel inlet so as to form another injection pattern while being operated in conjunction with the main plunger while being provided in the housing so that the up and down operations are performed according to the up and down operations of the main plunger, So that the performance of the diesel engine can be improved.

Description

TECHNICAL FIELD [0001] The present invention relates to a multi-fuel injection apparatus for a diesel engine,

The present invention relates to a multi-fuel injection device for a diesel engine, and more particularly, to a multi-fuel injection device for a diesel engine, and more particularly, to a multi-fuel injection device for a diesel engine.

2. Description of the Related Art Generally, a fuel injection device of a large-sized and medium-sized marine diesel engine is operated such that fuel injection is injected into a combustion chamber through an injector by operation of one fuel cam and a fuel pump for each cylinder installed in a camshaft, The fuel tank is connected by a flow path and is sent out by a plunger provided in the fuel pump. The fuel thus injected injects the fuel into the combustion chamber of the cylinder provided in the engine by the fuel injector through one flow path.

However, the fuel injection of the conventional diesel engine is operated by one plunger for each cylinder installed in the fuel pump. This is because the fuel injection is made to have a combustion pattern corresponding to one cycle by the cam, The fuel injection timing can not be changed during operation in order to solve the incomplete combustion.

In order to change the fuel injection timing during operation, a separate variable fuel injection timing control device is required, and a helical portion is formed in the plunger so as to inject only the main volume of the engine injection fuel in a predetermined pattern, .

In addition, in the conventional fuel injection system of a diesel engine, one injector is connected to one fuel pump to inject only one fuel, and it is difficult to adjust the pattern of fuel injection and the amount of fuel sent to each fuel injector .

Furthermore, when one plunger corresponds to the engine load of the entire region in one fuel pump, it is difficult to exert the optimum performance in all the load regions, and the fuel can not be actively coped with the load, .

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a fuel injection control system and a fuel injection control method, Pre-injection for complete combustion, and residual fuel after main fuel injection can be completely combusted through post-injection, thereby reducing the emission of noxious gases.

A fuel injection device for a diesel engine comprising a fuel injection pump for injecting fuel and injecting the fuel into a combustion chamber of each cylinder through an injector,

The fuel injection pump includes: a housing; A main plunger for injecting main fuel introduced through the main fuel inlet into the housing through a main fuel discharge port while being raised and lowered inside the housing; The sub fuel is sucked through the sub fuel inlet so as to form another injection pattern while being operated in conjunction with the main plunger while being provided in the housing so that the up and down operations are performed according to the up and down operations of the main plunger, So that the performance of the diesel engine can be improved.

The lower portion of the sub plunger includes an elastic member for compressing and extending the main plunger when the main plunger is moved up and down.

Also, the sub plunger has a structure in which a helical portion to be pre-injected is formed on the sub plunger so as to form a jet pattern different from that of the main plunger

The sub plunger has a protruding portion for performing post injection at a position spaced apart from the helical portion.

As described above, according to the present invention, the fuel injection pump constituting the combustion injection device is provided with the plunger having two different structures, one for spraying the main fuel and the other for performing the preinjection and post injection operations, By varying the pattern, the combustion performance during operation of the diesel engine is improved, thereby reducing the fuel consumption and reducing the exhaust gas.

In addition, it is possible to use another fuel in a duplex manner, so that a low-grade fuel such as HFO (Heavy Fuel Oil) can be continuously used in the main fuel discharge port. When the engine is initially started or is close to the port, (Marine Diesel Oil) or other environmentally friendly fuel through the sub-fuel discharge port to reduce the harmful gas.

1 is a view showing a fuel injecting apparatus according to an embodiment of the present invention.
FIG. 2 is a view illustrating a structure of a sub plunger capable of performing pre-injection and post injection while being provided in a fuel injection device according to an embodiment of the present invention.
3 (a) is a view showing a state in which fuel is injected into the fuel injecting apparatus according to an embodiment of the present invention.
FIG. 3 (b) is a view showing a state in which the fuel compressed through the main plunger and the sub plunger is injected through different discharge ports in the state of FIG. 3 (a).
FIG. 4 is a graph showing combustion patterns of three injection patterns, pre-injection, main injection, and post injection, in the fuel injection device according to an embodiment of the present invention.

Below. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1, the fuel injection device A according to the embodiment of the present invention includes a fuel injection pump 1, an injector 2 for injecting fuel through the fuel injection pump 1, The fuel injection pump 1 includes a main plunger 20 provided in a lower portion of the housing 10 and a fuel supply pump 2 located at an upper portion of the main plunger 20, And a sub-plunger (30) for interlocking with the injected fuel.

The main plunger 20 moves upward and downward linearly by driving a cam (not shown). The fuel is sucked through the main fuel intake port 11 formed on the circumferential surface of the housing 10, The upper end 21 of the main plunger 20 is compressed and injected through the main fuel discharge port 13 formed in the upper portion of the main fuel intake port 11 to the injector 2 to be injected into the cylinder .

A spindle 40 is provided between the upper end 21 of the main plunger 20 and the lower end 31 of the sub plunger 30 to cooperate with the main plunger 20 as the main plunger 20 moves.

The lower end 41 of the spindle 40 is in contact with the upper end 21 of the main plunger 20 and the upper end 42 of the spindle 40 is in contact with the lower end of the sub- .

That is, the sub plunger 30 and the spindle 40 may be integrally connected and interlocked with each other, or they may be separated from each other and contact with each other.

An elastic member 50 is fixed to the lower portion of the sub plunger 30 so as to be compressed as the upper end 42 of the spindle 40 ascends. The elastic member 50 uses a coil spring in this embodiment.

A sub fuel inlet 14 is formed along the upper side circumference of the housing 10 so that fuel can be sucked and discharged as the upper end 32 of the sub plunger 30 rises. And a sub fuel discharge port 15 is formed at the uppermost end.

In addition, adjustment means (not shown) (PVIT) (Pre Variable Injection (PVIT)) which is composed of a rack and a pinion can be provided at an approximately intermediate position of the sub plunger 30 so as to control the pre- Timing.

The sub plunger 30 is provided with a helical portion 33 protruding downward from an upper end 32 of the sub plunger 30 to perform a pre-injection operation, and a helical portion 33 And a protrusion 34 protruding from the outer surface of the sub plunger 30 so as to perform a post injection operation at a position spaced along the longitudinal direction of the sub plunger 30.

The main fuel and the sub fuel do not mean totally different fuels, but they can use the same type of fuel used in the diesel engine, or use different types of fuel.

3 (a), fuel is injected through the main fuel inlet 11 and the sub fuel inlet 14 of the housing 10 to inject fuel, as shown in FIG. 3 (a) the main plunger 20 is moved upward by driving of the cam to compress the fuel introduced into the space 12 through the main fuel intake port 11 As shown in Fig. 3 (b), is injected and supplied to the injector 2 shown in Fig.

At this time, the spindle 40 and the sub plunger 30 are interlocked with the main plunger 20 so that the spindle 40 and the sub plunger 30 move upward The fuel injected through the sub fuel inlet 14 is compressed by the sub plunger 30 moving upward and is injected through the sub fuel outlet 15 as shown in Figure 3 (b) .

The main plunger 20 and the sub plunger 30 that have risen again descend while the elastic member 50 rises when the spindle 40 rises. The spindle 40 is lowered by the repulsive force of the compressed elastic member 50 and at the same time the sub plunger 30 is also lowered to complete the operation of one cycle.

4, the sub-plunger 30 performs pre-injection and post-injection operations. Before the main injection by the main plunger 20 starts, the sub-plunger 30 slightly rises The main fuel is sucked through the main fuel intake port 11 in accordance with the continuous upward movement of the main plunger 20 and is compressed while being in the space portion 12 so that the main fuel is discharged from the main fuel discharge port 13 The main injection operation is performed.

The dotted line shows the pre-injection pattern for PVIT, indicating that the injection operation can be performed simultaneously with the main injection.

Since the pre-injection operation is performed preferentially through the sub plunger 30, the present invention is performed close to the complete combustion, and the residual fuel remaining after the main fuel is injected by the main plunger 20 into the sub plunger 30, So that contaminants can be removed from the combustion chamber of the cylinder and the emission of noxious gas can be reduced.

In other words, depending on the shape of the helical portion 34 protruding from the upper end portion 32 of the sub plunger 30 in accordance with the upward movement of the main plunger 20, the sub fuel introduced through the sub fuel intake port 14 flows into the sub- The main plunger 20 fully compresses the main fuel introduced into the space 12 and discharges the main fuel through the main fuel discharge port 15 so that the main fuel is discharged from the main fuel discharge port 15, The post injection operation is performed by the projecting portion 33 of the sub plunger 23 at the time when the compression process of the main plunger 20 is reduced and the pressure of the main plunger 20 is reduced to a substantially low pressure state so that the residual fuel is injected Thereby achieving the complete combustion as much as possible.

As described above, according to the present invention, the primary plunger performs the pre-injection operation by the sub-plunger before compression and injection of the main fuel injected into the main plunger 20, so that the main fuel is injected with the injection warm- The main fuel injecting operation is carried out by injecting the main fuel fully in accordance with the rise of the main plunger 20 so that the main fuel injecting operation of the main plunger 20 is completed, The sub-plunger 30 performs the post-injection operation again at the time when the operation is almost completed (at this time, the state where the main plunger 20 is lifted up), so that the complete combustion can be performed as much as possible.

While the invention has been shown and described with reference to exemplary embodiments thereof, it is evident that many changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims. It is an obvious fact that it is included in the scope.

A: fuel injection device
One ; Fuel injection pump
2: injector
10: Housing
11: Main fuel inlet
12: Space section
13: Main fuel outlet
14: sub fuel inlet
15: Sub fuel discharge port
20: main plunger
21:
30: Sub plunger
31:
32:
33: Helical portion
34: protrusion
40: spindle
41:
42:
50: elastic member

Claims

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And a fuel injection pump for injecting fuel and injecting the fuel into the combustion chamber of each cylinder through an injector, the fuel injection device comprising:
The fuel injection pump includes:
A housing;
A main plunger for injecting the main fuel introduced through the main fuel inlet into the housing through the main fuel outlet when the housing is lifted and lowered;
The sub fuel is sucked through the sub fuel inlet so as to form another injection pattern while being operated in conjunction with the main plunger while being provided in the housing so that the up and down operations are performed according to the up and down operations of the main plunger, A sub-plunger for injecting fuel into the diesel engine to improve the performance of the diesel engine;
And an elastic member installed at a lower portion of the sub plunger to compress and extend the main plunger when the main plunger is moved up and down.

And a fuel injection pump for injecting fuel and injecting the fuel into the combustion chamber of each cylinder through an injector, the fuel injection device comprising:
The fuel injection pump includes:
A housing;
A main plunger for injecting the main fuel introduced through the main fuel inlet into the housing through the main fuel outlet when the housing is lifted and lowered;
The sub fuel is sucked through the sub fuel inlet so as to form another injection pattern while being operated in conjunction with the main plunger while being provided in the housing so that the up and down operations are performed according to the up and down operations of the main plunger, And a sub plunger for injecting fuel into the diesel engine to improve the performance of the diesel engine,
Wherein the sub-plunger is formed with a helical portion protruding from the upper portion of the sub-plunger so as to be pre-injected so as to form an injection pattern different from that of the main plunger.

The method of claim 3,
Wherein the sub plunger has a protrusion for allowing post injection to be performed at a position spaced apart from the helical portion.