KR101789072B1

KR101789072B1 - common rail structure having one body style flow path member for pressure reducing

Info

Publication number: KR101789072B1
Application number: KR1020150151139A
Authority: KR
Inventors: 김형준; 윤성현; 박용순
Original assignee: 주식회사 현대케피코
Priority date: 2015-10-29
Filing date: 2015-10-29
Publication date: 2017-10-23
Also published as: KR20170050080A

Abstract

The present invention relates to a common rail structure having an integrated pressure reduction passage portion capable of reducing the number of assembling operations and parts, and includes: a main body portion having a rail inner space formed therein to supply fuel compressed by a high-pressure fuel supply pump to an injector; And a flow path portion integrally formed at an end of the main body portion so as to be connected to the internal space of the rail, wherein the flow path portion includes a high pressure flow path connected to the internal space of the rail in the flow path portion, Pressure passage, a low-pressure passage connected to the high-pressure passage, and a rod passage connected to the pressure chamber at a position opposite to the high-pressure passage, A rod of a magnetic path portion coupled to the flow path portion is moved or stopped in the rod passage portion and the pressure chamber to adjust the pressure of the internal space so that the high pressure flow path and the low pressure flow path are connected to each other ).

Description

[0001] The present invention relates to a common rail structure having an integral type pressure reducing passage,

[0001] The present invention relates to a common rail structure having an integral type pressure reduction passage portion, and more particularly, to a fuel rail or a common rail of a diesel engine integrally formed with a reduced pressure passage portion, Pressure-relief passage portion which is provided on the common rail.

Generally, the diesel engine forms the injection pressure by rotating the crankshaft by four strokes of suction, compression, explosion and exhaust in the cylinder. When the diesel engine rotates at low speed, the injection pressure becomes low, and when it rotates at high speed, the injection pressure becomes high.

In such diesel engines, electronic control of fuel injection and common rail for CRDI (Common Rail Direct Injection) may be used.

According to the common rail diesel engine, the fuel injection system is completely separate from the generation and injection of the injection pressure.

Such a fuel injection system can freely design the combustion and injection process since the engine design can separate the pressure generation and injection of the fuel.

The common rail according to the prior art receives the fuel stored in the fuel tank through the high-pressure fuel supply pump. This common rail is equipped with a pressure-reducing valve and a pressure-sensing sensor that detects the internal pressure of the common rail to regulate the pressure inside the rail. In the art, the pressure reducing valve is called "PRV (Pressure Reducing Valve)" or "PCV (Pressure Control Valve)".

Particularly, the pressure reducing valve is composed of a solenoid operated solenoid operated valve, a shaft to which the opening / closing force of the magnetic path portion is transmitted, and a valve portion coupled to the magnetic path portion and designed to be installed at the pressure valve mounting position of the common rail.

The valve portion of the conventional pressure reducing valve is provided with an outer body connected to the magnetic path portion and screwed to the installation position of the common rail and having an inlet and an inner body for providing the path of movement of the fuel or the shaft within the outer body.

In addition, the conventional valve unit has a plurality of parts such as a plurality of sealing parts provided inside the outer body with respect to the inner body and the magnetic path part, and a guide bushing guiding the movement of the shaft.

Particularly, since the conventional pressure reducing valve is stopped after rotation in the screw coupling manner and is coupled to the common rail, it is difficult to match the entrance and exit of the valve portion of the pressure reducing valve with the internal passage of the common rail.

In addition, the conventional pressure reducing valve is composed of a magnet portion and a valve portion, which makes the production of the pressure reducing valve very complicated and difficult.

That is, the valve portion of the conventional pressure reducing valve has a relatively large number of parts to be coupled only to the valve portion such as the outer body, the inner body, the sealing portion, the guide bushing, etc., And manufacturing cost increase.

In addition, the conventional pressure reducing valve has a disadvantage in that it has a relatively low durability and strength as compared with a common rail produced by forging.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a pressure reducing valve for an internal combustion engine, which has a reduced pressure relief passage portion (hereinafter, And the cost reduction can be achieved, and the common rail structure including the integral type pressure relief passage portion that maximizes the pressure drop efficiency while having the durability and strength equivalent to or the same as the common rail.

In order to accomplish the above object, the present invention provides a common rail structure including an integral type pressure reducing passage, comprising: a main body having a rail inner space formed therein to supply fuel compressed by a high-pressure fuel supply pump to an injector; And a flow path portion integrally formed at an end of the main body portion so as to be connected to the internal space of the rail, wherein the flow path portion includes a high pressure flow path connected to the internal space of the rail in the flow path portion, Pressure passage, a low-pressure passage connected to the high-pressure passage, and a rod passage connected to the pressure chamber at a position opposite to the high-pressure passage, A rod of a magnetic path portion coupled to the flow path portion is moved or stopped in the rod passage portion and the pressure chamber so as to connect or disconnect the high pressure flow path and the low pressure flow path to each other.

In the flow path portion, a low-pressure flow path connected to the pressure chamber is vertically connected to the high-pressure flow path, and the rod passage portion is coaxial with the high-pressure flow path.

The passage portion includes a passage inlet portion formed between the rail inner space and the high-pressure passage so as to have a diameter larger than the high-pressure passage and smaller than the inner space of the rail.

The flow path portion includes a valve seat which is formed at an outlet of the high pressure flow path with reference to a position opposite to the flow path inlet portion and which is in contact with or not in contact with an end of the rod.

The flow path portion may further include a drain fitting portion formed on an outer side of the flow path portion so as to be connected to the low pressure flow path, and the diameter of the passage of the drain fitting portion is relatively larger than the low pressure flow path.

The flow path portion further includes a buffer space portion extending toward the opposite side of the low pressure flow path and having an end closed.

Wherein the main body further includes a plurality of line fitting portions spaced apart from each other along the main body portion so as to receive the fuel or distribute the fuel to the injector side, A line fitting portion to which fuel of the fuel supply portion is supplied is disposed near the flow path portion.

The passage portion may further include a seating protrusion protruded from an end of the channel portion in a direction opposite to the inner space of the rail, the seating protrusion being wrapped around a casing end of the magnetic path portion, and the caulking or press- And is interlaced with the casing.

Wherein the seating projection has a caulking groove extending from the outer surface of the seating projection along the circumferential direction of the outer surface for seating the caulking portion formed by the caulking or the press fitting, A groove-shaped O-ring seating portion extending along the outer surface of the seating projection at a spaced apart position and being in parallel with the caulking groove; and an O-ring coupled to the O-ring seating portion.

In the common rail structure provided with the integral type pressure reduction flow path portion according to the present invention, the flow path portion is formed integrally with the common rail, so that the number of assembled parts of the pressure reducing valve is reduced while reducing the number of assemblies, thereby achieving cost reduction.

That is, since the common rail structure having the integral type pressure reduction flow path portion according to the present invention is assembled in such a manner that only the magnetic path portion is coupled to the flow path portion of the common rail, The assembling operation can be relatively easily performed without matching with the internal passage of the common rail.

Further, in the common rail structure provided with the integral type pressure reduction flow path portion according to the present invention, the durability and strength of the flow path portion are the same as or equivalent to those of the common rail, so that a common rail assembly of high strength and high quality can be manufactured.

Further, in the common rail structure provided with the integral type pressure reduction passage portion according to the present invention, a pressure chamber can be disposed between the high-pressure passage and the low-pressure passage to quickly induce the pressure drop, It can be quickly recovered to the fuel tank through the line.

Further, the passage portion according to the present invention is formed so as to reduce the pressure of the internal space of the rail in a multistage manner, which is advantageous in naturally stabilizing the pressure of the fuel.

Further, since the passage portion according to the present invention further includes a buffer space portion extending to the opposite side of the low-pressure passage, the impact force when the high-pressure passage and the low-pressure passage are connected to each other due to the opening and closing of the valve is attenuated through the buffer space portion, Vibration and noise can be relatively reduced.

In addition, since the number of parts is relatively small in comparison with the conventional pressure reducing valve, parts failing at parts can also be reduced, thereby minimizing the defective product ratio.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a common rail structure having an integral type pressure reduction channel unit according to an embodiment of the present invention; FIG.
2 is a cross-sectional view showing a coupling relationship between the common rail and the magnetic path portion shown in FIG. 1;
Fig. 3 is a plan view of the common rail shown in Fig. 1, in which a magnetic path portion and a pressure sensing sensor are combined. Fig.
Fig. 4 is an enlarged cross-sectional view of the square A of Fig. 3 in a valve closed state. Fig.
5 is an enlarged cross-sectional view of the square A of Fig.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. And is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined by the claims.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. &Quot; comprises " and / or "comprising" when used in this specification is taken to specify the presence or absence of one or more other components, steps, operations and / Or add-ons. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a plan view of a common rail structure having an integral type pressure reduction channel portion according to an embodiment of the present invention.

Referring to FIG. 1, the common rail of the present embodiment includes a main body 100 installed between a high-pressure fuel supply pump and an injector.

The main body 100 serves to distribute the high-pressure fuel compressed in the high-pressure fuel supply pump to a pressure required by the injector.

The body portion 100 includes a plurality of line fitting portions 110 and 120 on the outside thereof.

The line fitting portions 110 and 120 are connected to the inner space of the rail inside the body portion 100, respectively. The line fitting portions 110 and 120 are spaced along the body portion 100 to receive high-pressure fuel or distribute the fuel to the injector side.

One of the line fitting portions 110 connected to the high-pressure fuel supply pump among the plurality of line fitting portions 110 and 120 is connected to a fuel inflow line corresponding to a piping member such as a high-pressure hose, a pipe line, a tube, .

Further, one of the line fitting portions 120 connected to the injector among the plurality of line fitting portions 110 and 120 is connected to the fuel discharge line, which can be constituted by the piping member.

In addition, the main body 100 further includes a plurality of fixed ends 130 that can be installed in the engine room.

In addition, the main body 100 further includes a sensor fitting portion 140 for mounting the pressure sensing sensor. The sensor fitting portion 140 is formed between the line fitting portions 120. Here, the position of the sensor fitting part 140 is only an example, and may be different when considering the product standard or the interference relation with the peripheral structure, and may not be limited to a specific position.

FIG. 2 is a cross-sectional view showing a coupling relationship between the common rail and the magnetic path portion shown in FIG. 1. FIG.

Referring to FIG. 1 or FIG. 2, inside the main body 100, a rail inner space 101 filled with high-pressure fuel is formed before fuel compressed by the high-pressure fuel supply pump is supplied to the injector.

The body portion 100 includes an oil passage portion 200 integrally formed at an end of the body portion 100 so as to be connected to the inner space of the rail.

The flow path portion 200 functions to decouple the pressure of the high-pressure fuel to make low-pressure fuel, and then rapidly return the fuel to the fuel tank through the fuel return line coupled to the drain fitting portion 290. Here, the drop means that the pressure is suddenly attenuated or reduced.

The opening or closing of the valve with respect to the flow path portion 200 is performed by a magnetic path portion 300 to be coupled to the flow path portion 200 and a rod 310 to be moved by the magnetic path portion 300.

The rod 310 is a magnet armature coupled to the solenoid coil inside the magnetic path portion 300 and serves as a poppet for performing valve opening or closing.

The magnetic path portion 300 is a kind of solenoid type actuator that moves (for example, advances or retracts) or stops the rod 310 using an electromagnetic force or an elastic force. For example, the magnetic path portion 300 includes a spring for providing an elastic force to the rod 310, a sealing member, a connector, and a magnetic component.

The body portion 100 and the flow path portion 200 are structures capable of withstanding 1800 to 2000 atmospheric pressure and a temperature of -40 to 150 캜 in consideration of a fuel injection pressure of 1350 to 1600 atm or a safety flow.

The body portion 100 and the flow path portion 200 are fabricated to be a single body through forging. Then, the rail inner space 101 is formed inside the main body 100 through machining (e.g., perforation, milling, etc.). The inside of the flow path portion 200 is integrally provided with internal structures such as a high pressure flow path, a pressure chamber, a low pressure flow path, and a rod passage portion to be described later in detail through mechanical processing.

Since the line fitting portion 110 that receives the high pressure fuel from the line fitting portions 110 and 120 is disposed near the flow path portion 200, when the flow path portion 200 is opened, ), And through this, the fuel pressure can be rapidly lowered.

FIG. 3 is an enlarged cross-sectional view of the square A of FIG. 3 in the valve closed state, and FIG. 5 is a cross-sectional view of the square A of FIG. 3; And Fig.

3, the pressure sensing sensor 400 measures the pressure of the fuel introduced into the main body 100 through the sensor fitting portion 140 and outputs the measured value to the electronic control unit (ECU) As shown in FIG.

The electronic control unit ECU determines valve opening or closing with respect to the flow path portion 200 through the magnetic path portion 300 based on the measured value.

4, the flow path portion 200 includes a high pressure path 210, a pressure chamber 220, a low pressure path 230, a rod path portion 240, a flow path inlet portion 250, 260, a buffer space 270, a seating protrusion 280, and a drain fitting portion 290.

The high-pressure passage 210 is connected to the internal space 101 of the rail within the passage portion 200. Here, and in the following description, the meaning of connection may mean that space, space, or space and the flow path are connected to each other to form a fluid that can flow fluid.

The high pressure passage 210 may mean a fluid passage formed relatively small or narrower than the volume of the internal space 101 of the rail so as to reduce or drop the pressure of the internal space 101 of the rail.

The pressure chamber 220 is disposed between the high-pressure passage 210 and the low-pressure passage 230.

The pressure chamber 220 is connected to the high-pressure passage 210 so as to allow the fuel, which is fluid, to flow, and is formed to have a diameter larger than the high-pressure passage 210 and smaller than the internal space 101 of the rail. The pressure chamber 220 may have a volume of 1/20 to 1/30 of the size of the inner space 101 of the rail.

The pressure chamber 220 having such a volume exhibits a performance capable of momentarily receiving and discharging the high pressure fuel when the valve is opened so that the surge tank or the re-server tank capable of minimizing the pulsation pressure while promptly inducing the pressure drop .

If the volume of the pressure chamber 220 is less than or equal to the 1/20 volume, the pressure drop performance is lowered. If the volume of the pressure chamber 220 is 1/30 or more, the total volume of the common rail is increased, The fuel remains in the relatively long period, resulting in a problem that the recovery speed of the fuel is slowed down. Therefore, the numerical value of the pressure chamber 220 has a critical meaning.

The low-pressure passage 230 is connected to the pressure chamber 220 in a direction perpendicular to the extending direction of the high-pressure passage 210.

That is, in the flow path portion 200, a low pressure pathway 230 connected to the pressure chamber 220 is connected to the high pressure pathway 210 in the vertical direction, and the rod pathway portion 240 is connected to the high pressure pathway 210 May be coaxial. In other words, the term coaxial means that the axial direction passing through the center of the rod passage portion 240 is the same as the axial direction passing through the center of the high-pressure flow passage 210.

Therefore, the rod passage portion 240 is connected to the pressure chamber 220 at a position opposite to the high-pressure flow passage 210, while being coincident with the center of the high-pressure flow passage 210.

The magnetic path portion 300 moves or stops the rod 310 in the rod passage portion 240 and the pressure chamber 220 by an electromagnetic force or an elastic force generated by the magnetic path portion 300 to adjust the pressure of the inner space of the rail .

Through the movement or stop of the rod 310, the high-pressure passage 210 and the low-pressure passage 230 are connected to each other, that is, the valve is opened, or the valve is closed, that is, the valve is closed.

The passage inlet portion 250 is formed between the rail inner space 101 and the high pressure passage 210 so as to have a larger diameter than the high pressure passage 210 and a smaller diameter than the rail internal space 101.

According to a spatial feature, the rail inner space 101, which is the largest space, is sequentially reduced through the flow path inlet portion 250 and the high pressure flow path 210. Accordingly, the pressure of the fuel in the rail inner space 101 is stepwise or multi-stepped.

As a result, an excessive pressure drop can be prevented, and the resulting impact force or noise generation can be relatively reduced.

The valve seat 260 is formed at a position connected to the pressure chamber 220 with reference to a position opposite to the flow passage inlet portion 250. Here, the valve seat 260 may refer to an outlet or an outlet edge of the high-pressure flow passage 210. The valve seat 260 makes a valve closing through metal-to-metal contact with the end of the rod 310, or makes contact with the end of the rod 310 to make a valve opening.

The end of the rod 310 of the magnetic path portion 300 is formed in a hemispherical shape. The hemispherical shape facilitates contact with the valve seat 260. In addition, the hemispherical shape plays a role in realizing reliable contact even if there is a slight difference in the center of the rod 310 or in the center of the valve seat 260.

Further, a guide protrusion 311 of a circular disc shape having a diameter larger than the diameter of the end of the rod 310 is further formed at a position apart from the end of the rod 310. The projecting direction of the guide projection 311 is directed toward the low-pressure passage 230.

The corner portion between the outer peripheral surface of the end of the rod 310 and the side surface of the guide projection 311 is rounded.

The fuel introduced into the pressure chamber 220 is radially diffused along the surface of the round shape and the guide projection 311. Here, the radial direction includes the direction toward the low-pressure flow path 230. That is, the fuel introduced into and diffused into the pressure chamber 220 can be guided by the round shape and the guide protrusion 311 to easily escape to the low-pressure flow path 230.

The guide protrusions 311 are formed symmetrically with respect to the protruding direction of the protrusions 311.

The fuel filled in the pressure chamber 220 can be guided by the round shape and the guide protrusion 311 and can smoothly and smoothly escape toward the low pressure passage 230. By this rounded shape and the guide projection 311, the fuel can be rapidly flowed, and the pressure drop can be efficiently performed.

The diameter of the rod 310 forming the guide protrusion 311 is smaller than the diameter of the rear body which is moved in airtight contact with the rod passage 240, The total weight of the rod 310 can be relatively reduced. Thus, there is an advantage that the magnetic load of the magnetic path portion 300 can be minimized.

The buffer space 270 is connected to the pressure chamber 220, extends toward the opposite side of the low-pressure flow path 230, and has a closed end. The buffer space 270 may be spaced apart along the circumferential direction of the pressure chamber 220 by one or more.

The fuel that has not escaped to the low-pressure flow path 230 immediately after the pressure drop of the fuel in the pressure chamber 220 is temporarily accommodated in the cushioning space portion 270, the shock due to the pressure drop is buffered do.

The seating protrusion 280 is a tubular or skirt-like protruding structure that opens toward the magnetic path portion 300 and serves as a foundation for mounting the magnetic path portion 300. That is, the seating protrusion 280 protrudes from the end of the passage portion 200 in the direction opposite to the inner space 101 of the rail.

The outer diameter of the seating projection 280 is smaller than the diameter of the flow path portion 200. It is possible to couple the portion 300 with a relatively small diameter or a small size.

For example, the seating protrusion 280 is formed in a size that can be inserted into the inner diameter of the casing end 301 of the magnetic path portion 300.

The seating protrusion 280 is wrapped around the casing end 301 of the magnetic path portion 300. The seating protrusions 280 and the casing ends 301 of the magnetic path portions 300 are coupled to each other by the plurality of caulking portions 302 formed by caulking or press fitting. The caulking portions 302 may be spaced apart from each other along the circumference of the casing end 301.

At this time, the inner surface of the magnetic path portion 300 may be in close contact with the outer surface of the seating projection portion 280 with the sealing member or the like interposed therebetween, and the fuel may be treated not to leak out of the magnetic path portion 300.

4 and 5, the seating protrusion 280 is formed on the outer surface of the seating protrusion 280 for the seating of the caulking portion 302 made by the caulking or the press- And the caulking groove 281 extending along the outer surface of the seating protrusion 280 at a position spaced apart from the caulking groove 281 in the direction of the self- Shaped o-ring seating portion 282, and an O-ring 285 coupled to the o-ring seating portion 282. The O-

An O-ring coupling portion 303 is formed on the inner peripheral surface of the casing end 301 of the magnetic path portion 300 so that the O-ring 285 can be positively positioned at a position corresponding to the O-ring seating portion 282.

The O-ring 285 is a sealing member interposed between the inner surface of the magnetic path portion 300 and the outer surface of the seating projection portion 280, and can play a role of preventing leakage or preventing pressure drop.

The drain fitting portion 290 is formed on the outside of the flow path portion 200 so as to pass through the low pressure flow path 230. At this time, the diameter of the drain passage 291 of the drain fitting portion 290 is relatively larger than that of the low-pressure passage 230, so that the flow rate of the low-pressure fuel can be increased.

Hereinafter, valve opening and closing of the common rail structure having the integral type pressure reduction passage portion according to the present embodiment will be described.

4, the end of the rod 310 closes the outlet of the valve seat 260 between the pressure chamber 220 and the high-pressure flow path 210, corresponding to the valve closing operation of the magnetic path portion 300. [

The pressure of the fuel in the inner space 101 of the rail of the main body 100 may increase to a value larger than the set value.

The measured value measured through the pressure sensor in this case is input to the electronic control unit (ECU).

The electronic control unit ECU moves the rod 310 of the magnet portion 300 based on the measured value. As a result, the valve is opened as the outlet of the valve seat 260 between the pressure chamber 220 and the high-pressure flow path 210 is opened, and the state shown in FIG. 5 is obtained.

5, the fuel in the rail inner space 101 of the main body 100 is reduced in pressure by a plurality of steps through the flow path inlet 250 and the high-pressure flow path 210 to be supplied to the pressure chambers 220 ).

The low-pressure fuel introduced into the pressure chamber 220 is returned to the fuel return line (not shown) and the fuel tank via the low-pressure passage 230 and the drain passage 291 of the drain fitting portion 290.

In addition, the fuel in the rail inner space 101 of the main body 100 is returned to the fuel tank side, so that the pressure drop is made as if the pressure in the rail inner space 101 is sharply lowered.

The measured value corresponding to this pressure drop is directly inputted to the electronic control unit (ECU) through the pressure sensor.

The electronic control unit ECU reversely moves the rod 310 of the self-arm portion 300 so that an excessive pressure drop is not generated but is kept within the set value range. As a result, the valve is closed so that the outlet of the valve seat 260 between the pressure chamber 220 and the high-pressure flow path 210 becomes clogged, and the state shown in FIG. 4 is obtained again.

That is, through the repetition of the state of FIG. 4 and the state of FIG. 5, the pressure of the fuel in the rail inner space 101 of the main body 100 is maintained within the set value range.

The foregoing description is merely illustrative of the technical idea of the present invention and various changes and modifications may be made without departing from the essential characteristics of the present invention. Therefore, the embodiments described in the present invention are not intended to limit the scope of the present invention, but are intended to be illustrative, and the scope of the present invention is not limited by these embodiments. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents, which fall within the scope of the present invention as claimed.

100: main body 101: inner space of the rail
110, 120: Line fitting portion 130: Fixed end
140: sensor fitting portion 200:
210: high pressure fluid passage 220: pressure chamber
230: low pressure passage 240: rod passage portion
250: flow path inlet part 260: valve seat
270: buffer space part 280:
290: drain fitting portion 300:
310: load 400: pressure sensor

Claims

A main body portion having a rail inner space formed therein to supply the fuel compressed by the high-pressure fuel supply pump to the injector; And
And a channel portion integrally formed at an end of the main body portion to be connected to the inner space of the rail,
The flow-
A high-pressure passage connected to the internal space of the rail in the passage portion,
A pressure chamber which is connected to the high pressure passage so as to allow the fuel to flow and is formed at one end of the high pressure passage and has a diameter larger than the diameter of the high pressure passage and smaller than the internal space of the rail,
A low-pressure flow passage connected to the pressure chamber,
And a rod passage portion connected to the pressure chamber at a position opposite to the high pressure passage,
A rod of a magnetic path portion coupled to the flow path portion is moved or stopped in the rod passage portion and the pressure chamber to adjust the pressure of the inner space of the rail to connect or disconnect the high pressure passage and the low pressure passage,
Wherein the end of the rod is formed in a hemispherical shape and the corner portion between the outer circumferential surface of the end of the rod and the side surface of the guide protrusion is formed in a round shape and at a position spaced apart from the end of the rod, Wherein a guide protrusion protruding in a direction toward the low pressure passage is formed in a large circular disk shape so that the fuel introduced into the pressure chamber diffuses in a radial direction along the corner portion formed in the round shape and the surface of the guide projection, The front body diameter of the rod is smaller than the rear body diameter
And an integral pressure-reducing channel portion.

The method according to claim 1,
The flow-
A low-pressure passage connected to the pressure chamber is connected to the high-pressure passage in the vertical direction, and the rod passage portion is coaxial with the high-
Wherein the pressure reducing passage has an integral pressure reducing passage portion.

The method according to claim 1,
The flow-
And a passage inlet formed between the rail inner space and the high-pressure passage so as to have a diameter larger than the high-pressure passage and smaller than the internal space of the rail
Wherein the pressure reducing passage has an integral pressure reducing passage portion.

The method of claim 3,
The flow-
And a valve seat formed at an outlet of the high-pressure flow passage with respect to a position opposite to the flow passage inlet portion, the valve seat being in contact with or not in contact with an end of the rod
Wherein the pressure reducing passage has an integral pressure reducing passage portion.

The method according to claim 1,
The flow-
And a drain fitting portion formed on an outer side of the flow path portion so as to be connected to the low pressure flow path,
Wherein the diameter of the passage of the drain fitting portion is formed relatively larger than the low-pressure passage
Wherein the pressure reducing passage has an integral pressure reducing passage portion.

The method according to claim 1,
The flow-
Further comprising a cushioning portion extending toward the opposite side of the low-pressure passage and having an end closed
Wherein the pressure reducing passage has an integral pressure reducing passage portion.

The method according to claim 1,
Wherein,
Further comprising a plurality of line fitting portions spaced apart from each other along the main body portion to receive the fuel or distribute the fuel to the injector side,
And a line fitting portion for receiving high-pressure fuel among the line fitting portions is disposed near the flow path portion
Wherein the pressure reducing passage has an integral pressure reducing passage portion.

3. The method of claim 2,
The flow-
Further comprising a seating protrusion protruding from an end of the channel portion in a direction opposite to the inner space of the rail,
The seating protrusion is wrapped around the casing end of the magnetic path portion and is coupled to the casing of the magnetic path portion by caulking or press fitting
Wherein the pressure reducing passage has an integral pressure reducing passage portion.

9. The method of claim 8,
The mounting projection part
A caulking groove extending along the circumferential direction of the outer surface of the outer surface of the seating protrusion for seating the caulking portion formed by the caulking or the press fitting,
A groove-shaped o-ring seating portion extending along the outer surface of the seating projection at a position spaced apart from the caulking groove in the direction of the magnetic path,
And further comprising an O-ring coupled to the O-ring seating portion
Wherein the pressure reducing passage has an integral pressure reducing passage portion.