Liquid fuel supply system and vessel provided with the same

Abstract

This disclosure relates to a liquid fuel supply system and a vessel equipped with the liquid fuel supply system. The liquid fuel supply system according to this disclosure includes: an engine structure (6) disposed in the engine compartment; a liquid fuel tank (30) for storing liquid fuel in an area isolated from the engine compartment; a low-pressure liquid fuel pump (31) for supplying liquid fuel from the liquid fuel tank (30) to the engine; a low-pressure delivery pipe (32) for delivering low-pressure liquid fuel from the low-pressure liquid fuel pump (31) to the engine structure (6) in the engine compartment; a liquid fuel pressurization unit (100) for pressurizing the low-pressure liquid fuel received from the low-pressure delivery pipe (32) to high pressure and discharging it; a high-pressure liquid fuel inlet pipe (50) made of high-pressure double-walled pipe through which high-pressure liquid fuel discharged from the liquid fuel pressurization unit (100) is delivered toward the cylinder; a common rail (60) for distributing the high-pressure liquid fuel delivered from the high-pressure liquid fuel inlet pipe (50) to each cylinder; and an outlet pipe (70) made of double-walled pipe connected to the outlet of the common rail (60).

Description

Technical Field

[0001] This disclosure relates to a system for supplying liquid fuel to an internal combustion engine, and more particularly to a liquid fuel supply system for improving the reliability and safety of the liquid fuel supply system and a ship equipped with the liquid fuel supply system. Background Technology

[0002] Recently, in order to reduce ship exhaust emissions, a low flash point fuel supply system (LFSS) is being researched, which is suitable for the stable use of low flash point environmentally friendly fuels such as liquefied petroleum gas (LPG), methanol, ammonia and ethanol in ships.

[0003] However, because low-flash-point environmentally friendly fuels are easily ignited even at low temperatures, leaks from delivery pipes on ships or in engine rooms can pose a very serious danger.

[0004] exist Figure 1 The image shows a fuel supply system in a ship that uses liquid fuels (e.g., low flash point fuels such as methanol) in the relevant technology.

[0005] refer to Figure 1 The liquid fuel supply system in the related technology includes a fuel storage tank 2 with a double bottom structure, a high-pressure pump 4 driven by an electric motor, and a high-pressure common rail system 60 with an engine structure 6.

[0006] The high-pressure pump 4 for methanol, driven by an electric motor, is installed in a separate pump room space, which is separated from the engine room by partition walls, etc., in order to meet the ship's safety regulations regarding the risk of fire or explosion.

[0007] Furthermore, the high-pressure pump 4 is connected to the fuel storage tank 2 via a low-pressure double-walled pipe 8, and to the engine's common rail system 60 via a high-pressure double-walled pipe 10. Thus, the high-pressure pump 4 draws fuel from the fuel storage tank 2 through the low-pressure double-walled pipe 8, and the pressurized liquid fuel in the high-pressure pump 4 travels a long distance through the high-pressure double-walled pipe 10 and is supplied to the common rail system 60.

[0008] Thus, for safety reasons, the electric-driven high-pressure pump 4 is installed in a separate space from the engine room, inevitably making the length of the high-pressure double-walled pipe 10 used to transport high-pressure fuel from the high-pressure pump 4 to the common rail system 60 very long. For example, the length of the high-pressure double-walled pipe 10 varies depending on the size of the ship, reaching a maximum of 100 meters. Since this high-pressure double-walled pipe 10 is more expensive than the low-pressure double-walled pipe 8, the investment cost inevitably increases with the increase in the length of the high-pressure double-walled pipe 10.

[0009] Furthermore, since the high-pressure double-layer pipe 10 must traverse long distances within the ship, dangerous sections such as those prone to liquid fuel leaks are increased, which is detrimental to the ship's safety and introduces additional costs and risks, such as the need to provide additional detection devices for leaks or safety equipment to prevent the ignition or explosion of leaked fuel.

[0010] At the same time, leak points must be found in the common rail used to distribute liquid fuel to each engine cylinder and the liquid fuel supply line used to deliver high-pressure liquid fuel to the common rail, and leak testing should be conducted after equipment assembly or if leaks occur during engine operation.

[0011] However, in order to accurately identify the location or section of the leak, it is necessary to dismantle the common rail and liquid fuel supply lines one by one, or to significantly increase downtime in order to find the leak location. Summary of the Invention

[0012] Technical issues

[0013] This disclosure is made to solve all the problems in the related art as described above, and the purpose of this disclosure is to improve the reliability and safety of liquid fuel supply systems as a whole.

[0014] The overall objectives as described above include the detailed objectives outlined below.

[0015] In other words, one objective is to reduce leakage problems caused by long-distance transport of high-pressure liquid fuel by providing a novel liquid fuel supply device, while eliminating long-term use sections of high-pressure double-layer pipes in areas other than the engine room. The liquid fuel supply device pressurizes low-pressure liquid fuel in the engine room via a liquid fuel pressurization device and supplies the fuel to the cylinders.

[0016] In addition, another objective is to structurally optimize the high-pressure liquid fuel supply pipeline and the common rail for supplying high-pressure liquid fuel to the cylinder from the perspectives of manufacturing, assembly and operation.

[0017] In addition, another objective is to detect leaks in each section by inserting leak detectors at each critical point in the high-pressure liquid fuel supply line, thereby enabling rapid and accurate identification of defective parts that leak during engine manufacturing or leak testing during engine operation, and allowing for corrective action.

[0018] In addition to the detailed objectives described above, this disclosure also has various detailed objectives disclosed in the section describing embodiments of the invention below, in order to improve the overall reliability and safety of liquid fuel supply systems.

[0019] Technical solution

[0020] To achieve the above objectives, this disclosure describes a liquid fuel supply system comprising: an engine structure 6 disposed within the engine compartment; a liquid fuel tank 30 configured to store liquid fuel in an area isolated from the engine compartment; a low-pressure liquid fuel pump 31 configured to supply liquid fuel from the liquid fuel tank 30 to the engine; a low-pressure delivery pipe 32 configured to deliver low-pressure liquid fuel from the low-pressure liquid fuel pump 31 to the engine structure 6 within the engine compartment; a liquid fuel pressurization unit 100 configured to pressurize the low-pressure liquid fuel received from the low-pressure delivery pipe 32 to high pressure and discharge it; a high-pressure liquid fuel inlet pipe 50, made of high-pressure double-walled tubing, for delivering high-pressure liquid fuel discharged from the liquid fuel pressurization unit 100 toward cylinders; a common rail 60 configured to distribute the high-pressure liquid fuel delivered from the high-pressure liquid fuel inlet pipe 50 to each cylinder; and an outlet pipe 70, made of double-walled tubing, connected to the outlet of the common rail 60.

[0021] The liquid fuel supply system according to this disclosure may include: a low-pressure hydraulic pump 23 configured to supply low-pressure operating oil to a liquid fuel pressurization unit 100; and an electric motor 22 configured to drive the low-pressure hydraulic pump 23, wherein the liquid fuel pressurization unit 100 can pressurize low-pressure liquid fuel into high-pressure liquid fuel under the pressure of the low-pressure operating oil supplied from the low-pressure hydraulic pump 23.

[0022] In the liquid fuel supply system according to the present disclosure, the liquid fuel pressurization unit 100 may be configured as a piston-operated pressurization unit, which is configured to operate the piston by receiving pressure from low-pressure operating oil supplied from the low-pressure hydraulic pump 23 to perform pressurization to high pressure.

[0023] In the liquid fuel supply system according to the present disclosure, the liquid fuel pressurization unit 100 may include: a piston pump unit 500 configured to pressurize low-pressure liquid fuel to high pressure and discharge it under the pressure of operating oil; and an operating oil control unit 200 configured to control the supply and discharge of low-pressure operating oil to the piston pump unit 500.

[0024] In the liquid fuel supply system according to the present disclosure, the piston pump unit 500 includes a plurality of plunger pump sections P500 arranged in parallel, and the operating oil control unit 200 may include a plurality of valve sections V300, which are configured to supply and discharge low-pressure operating oil to the plurality of plunger pump sections P500 respectively, and the plurality of valve sections V300 may be configured to operate sequentially at equal intervals, such that the plurality of plunger pump sections P500 are pressurized and discharge liquid fuel sequentially at equal intervals.

[0025] In the liquid fuel supply system according to the present disclosure, the operating oil control unit 200 may include: a rotary valve shaft 300 configured to control the flow direction of operating oil in a control cylinder 212; and a plurality of operating oil supply ports 214 respectively connected to a plurality of plunger pump sections P500 from the control cylinder 212, wherein a plurality of valve sections V30 may be formed on the outer periphery of the valve shaft 300, thereby maintaining an axial spacing corresponding to the positions of the plurality of operating oil supply ports 214, while maintaining an equal phase difference in the rotational direction.

[0026] In the liquid fuel supply system according to the present disclosure, a valve section V300 may include an inlet channel 304 and an outlet channel 306. The inlet channel 304 is configured to supply operating oil to the plunger pump section P500 when it encounters and communicates with the operating oil supply port 214, and the outlet channel 306 is configured to discharge operating oil from the plunger pump section P500 when it encounters and communicates with the operating oil supply port 214.

[0027] In the liquid fuel supply system according to the present disclosure, in a valve section V300, a total of two inlet grooves 304 can be formed in a symmetrical shape on the left and right sides of the cross section of the valve shaft 300, and a total of two outlet grooves 306 can be formed in a symmetrical shape on the left and right sides in a direction orthogonal to the inlet grooves 304, such that the valve shaft 300 performs two operating oil supply / discharge operations and two liquid fuel pressurization operations for each rotation.

[0028] In the liquid fuel supply system according to this disclosure, a plunger pump section P500 of the liquid fuel pressurization unit 100 may include: a low-pressure cylinder 502 forming a low-pressure chamber C1 filled with operating oil through an operating oil supply port 214 and having a large diameter; a high-pressure cylinder 504 forming a high-pressure chamber C2 filled with low-pressure liquid fuel located on the opposite side of the low-pressure chamber C1 and having a diameter smaller than that of the low-pressure cylinder 502; a pressurizing plunger 600, wherein a low-pressure piston 610 is formed on one side and installed in the low-pressure cylinder 502, and a high-pressure piston 620 is formed on the opposite side and installed in the high-pressure cylinder 504; and a high-pressure liquid fuel discharge flow path 514 configured to deliver the high-pressure liquid fuel, pressurized by the high-pressure piston 620 and increased in pressure, toward the cylinder.

[0029] In the liquid fuel supply system according to this disclosure, the high-pressure liquid fuel inlet pipe 50 can be made of a high-pressure double-walled pipe having an inner pipe 52 forming a main fuel pipe 52a inside and an outer pipe 54 maintaining an annular space 54a outside the inner pipe 52. The high-pressure liquid fuel inlet pipe 50 can be divided into a first inlet pipe 50a located upstream in the direction of liquid fuel flow and a second inlet pipe 50b located downstream in the direction of liquid fuel flow. The separated first inlet pipe 50a and second inlet pipe 50b can be connected to each other by a leak detection connector 700, from which a leak detection separator 850 can be attached and detached.

[0030] In the liquid fuel supply system according to the present disclosure, the leak detection connection 700 may include: a connecting flange 710 with a double-walled tube structure connected to a first inlet pipe 50a; and a leak detection block 750 connected to a second inlet pipe 50b, which is fastened to abut against the connecting flange 710 and configured to allow the leak detection separator 850 to be inserted.

[0031] In the liquid fuel supply system according to this disclosure, the leak detection block 750 may include: a first annular space connecting groove 782 communicating with the annular space of the connecting flange 710 and a second annular space connecting groove 792 communicating with the annular space 54a of the second inlet pipe 50b; a first separator insertion hole 810, connected across one end of the width direction of the first annular space connecting groove 782 and the second annular space connecting groove 792; a second separator insertion hole 820, connected across the other end of the width direction of the first annular space connecting groove 782 and the second annular space connecting groove 792; and a first connecting hole 830, which crosses the first separator insertion hole. One end of the inlet 810 is connected to the middle of the second separator insertion hole 820; and a second connecting hole 840 is connected across one end of the plug 802 and the first separator insertion hole 810, wherein by inserting the leak detection separator 850 into each of the first separator insertion hole 810 and the second separator insertion hole 820, the communication connection between the two ends of the first annular space connection groove 782 and the second annular space connection groove 792 can be closed, and the end of each separator 850 can be exposed to the interior of the first connecting hole 830 communicating only with the first annular space connection groove 782 and the interior of the second connecting hole 840 communicating only with the second annular space connection groove 792.

[0032] In the liquid fuel supply system according to this disclosure, the common rail 60 can be configured as a block common rail 60a, which includes: a plurality of high-pressure blocks 1000 arranged in parallel with the engine cylinders and mounted on the engine block; jumping blocks 2000 having a solid block body and connected between adjacent high-pressure blocks 1000; a main fuel line connection hole 1100-1, which is penetrated to form a through connection between the high-pressure blocks 1000 and the jumping blocks 2000 at the center of their cross sections, while branching through towards the engine block; and an annular space connection groove 1100-2, which is penetrated to form a through connection between the high-pressure blocks 1000 and the jumping blocks 2000, while being connected in parallel with the main fuel line connection hole 1100-1 and remaining horizontal with no height difference relative to the ground.

[0033] In the liquid fuel supply system according to this disclosure, the annular space connection groove 1100-2 may be configured with an upper annular space connection groove 1100-2a and a lower annular space connection groove 1100-2b that penetrate through the upper and lower parts of the main fuel pipeline connection hole 1100-1, respectively, to connect the high-pressure block 1000 and the jump block 2000 through, while being connected in parallel with the main fuel pipeline connection hole 1100-1 and maintaining a horizontal position relative to the ground without any height difference.

[0034] In the liquid fuel supply system according to the present disclosure, the jump block 2000 may include a separator attachment / removal part 2004 at the midpoint of the block body part 2001 in the longitudinal direction, wherein a leak detection separator 850 for detecting whether a leak occurs inside the upper annular space connection groove 1100-2a and the lower annular space connection groove 1100-2b may be attached / removed from the separator attachment / removal part 2004.

[0035] In the liquid fuel supply system according to this disclosure, the common rail 60 can be configured as a jumping pipe common rail 60b, which includes: a plurality of high-pressure blocks 1000 arranged in parallel with the engine cylinders and mounted on the engine block; and a jump pipe 3000 connected between adjacent high-pressure blocks 1000, wherein the jump pipe 3000 may include: a double-bend 3100 having an inner pipe 3152 forming a main fuel line 3152a at the center, and an outer pipe 3154 maintaining an annular space 3154a outside the inner pipe 3152; and a leak detection block 750 disposed at the upstream end of the double-bend 3100, connected to abut the downstream flange 1003 of the high-pressure block 1000, and configured such that a separator 850 for detecting liquid fuel leaks in the annular space 3154a can be attached / removed.

[0036] Ships according to this disclosure may include any of the liquid fuel supply systems described above.

[0037] Beneficial effects

[0038] According to the liquid fuel supply system and vessel disclosed herein, instead of the high-pressure pumps conventionally located in the pump room adjacent to the liquid fuel storage tank, the liquid fuel pressurization unit of this disclosure can be directly installed in the engine in the engine room to pressurize the low-pressure liquid fuel and then supply it to the engine cylinders.

[0039] Therefore, since low-pressure fuel can be delivered directly from the liquid fuel tank to the liquid fuel pressurization unit in the engine room, the use of high-pressure double-layer piping can be eliminated, and low-pressure delivery piping can be used in long sections from the liquid fuel tank to the engine room. Thus, simply replacing high-pressure double-layer piping with low-pressure delivery piping can reduce equipment costs.

[0040] Furthermore, by eliminating the risk of leakage associated with the delivery of high-pressure fuel in the section from the pump room to the engine room, the safety of the vessel can be improved, and an economical and safe fuel supply system and vessel can be achieved, which does not require additional detection devices to prevent such fuel leaks, safety equipment to prevent the ignition or explosion of leaked gases, etc.

[0041] Furthermore, according to this disclosure, when only low-pressure operating oil is supplied to the liquid fuel pressurization unit, the low-pressure liquid fuel can be pressurized into the high-pressure operating oil required by the engine cylinders. Therefore, only a low-pressure hydraulic pump is needed instead of a conventional high-pressure pump. The low-pressure hydraulic pump is the only pump in the liquid fuel supply system of this disclosure, and due to its small displacement and size, it can be installed in the engine compartment or directly on the engine structure. Therefore, the pump can be installed without occupying excessive space in the engine compartment, and most maintenance work on the liquid fuel supply system, including the pump, can be easily performed within the engine compartment.

[0042] Furthermore, since the liquid fuel pressurization unit of this disclosure has an operating oil valve device of the type that rotates the valve shaft, wherein the valve part is formed on the outer periphery, a simple and compact operating oil control unit can be realized.

[0043] Furthermore, by having such a valve structure, the pressurized plunger performs two compression strokes for each rotation of the valve shaft, shortening the time interval between the discharge of high-pressure liquid fuel, thereby reducing pressure pulsation by maintaining a common rail and uniform peak pressure inside.

[0044] In addition, this disclosure provides a structure in which multiple valve sections are arranged on a rotary valve shaft, and multiple plunger pump sections are correspondingly arranged in parallel, and an overlapping design of the operating oil supply valve (inlet groove) is also provided. Therefore, the discharge interval of the high-pressure liquid fuel becomes narrower, and the discharge processes between the valve sections overlap, thereby more reliably reducing pressure pulsations while maintaining peak pressures more uniformly within the common rail and liquid fuel discharge ports.

[0045] Furthermore, according to this disclosure, a leak detection unit is installed at a specific point in each connection section of the high-pressure liquid fuel inlet line, outlet line, and common rail. While the leak detection unit typically connects the main fuel line and the annular space, a configuration is provided that allows for the insertion of a leak detector when necessary. That is, the leak detector can be inserted simply by disconnecting the plug of the leak detection unit and inserting a separator. Therefore, fuel leaks in each predetermined section can be easily and accurately detected simply by inserting a separator into each leak detection unit. This allows for the rapid and accurate identification and intervention of defective sections where leaks occur during engine manufacturing or leak testing during engine operation.

[0046] Furthermore, according to this disclosure, a block-type common rail is provided, wherein high-pressure blocks are connected by block-type jumpers, the interior of which is completely filled, and a main fuel line connection hole and an annular space connection groove are formed through the jumper. According to this block-type common rail, the height difference or gradient of the annular space connection between the high-pressure blocks and the jumpers can be eliminated, allowing fuel leaking into the annular space to flow and be discharged smoothly. Attached Figure Description

[0047] Figure 1 This is a view illustrating a liquid fuel supply system for ships in the relevant art.

[0048] Figure 2 This is a view showing the construction of the liquid fuel pressurization unit of the liquid fuel supply system according to the present disclosure, and its operating oil and fuel system.

[0049] Figure 3 This is a view showing the construction of an engine and a ship equipped with a liquid fuel supply system according to this disclosure.

[0050] Figure 4 This is a perspective view showing the appearance of the liquid fuel pressurization unit according to the present disclosure.

[0051] Figure 5 Seen from another direction Figure 4 A view showing the exterior of the liquid fuel pressurization unit.

[0052] Figure 6 It is along Figure 5 The view is a sectional view of line II, and is used to illustrate the process of pressurizing low-pressure liquid fuel to high pressure and discharging it through the pump operation of the liquid fuel pressurization unit.

[0053] Figure 7 It is along Figure 5The view is a sectional view of line II and is used to illustrate the process of low-pressure liquid fuel being refilled into the high-pressure chamber of the liquid fuel pressurization unit.

[0054] Figure 8 It is a view used to illustrate the changes in valve opening / closing and plunger displacement based on the rotation of the valve shaft.

[0055] Figure 9 This is a perspective view showing the overall horizontal cross-sectional structure of the liquid fuel pressurization unit according to the present disclosure.

[0056] Figure 10 yes Figure 9 Floor plan.

[0057] Figure 11 It is along Figure 5 The view is a sectional view along line II-II, and is used to illustrate the valve shaft and discharge flow path of the liquid fuel pressurization unit.

[0058] Figure 12 It is along Figure 5 The view is a sectional view along line III-III, and is used to illustrate the construction of the valve shaft and operating oil inlet of the liquid fuel pressurization unit.

[0059] Figure 13 These are views (perspective and plan views) showing the outline of the valve shaft of a liquid fuel pressurization unit with multiple valve sections according to this disclosure.

[0060] Figure 14 It is shown in an enlarged manner Figure 13 A view of the operating oil supply flow path and a valve section.

[0061] Figure 15 These are views (perspective and sectional views) used to illustrate the phase difference between the plurality of inlet and outlet grooves in the valve shaft according to this disclosure.

[0062] Figure 16 This is a view used to illustrate the valve overlap between multiple inlet slots in the valve shaft according to this disclosure.

[0063] Figure 17 It is a graph used to illustrate the overlap range of the multiple inlet grooves in the valve shaft according to this disclosure.

[0064] Figure 18 This is a view used to illustrate the formation state of the peak pressure in the liquid fuel discharge section (high-pressure chamber and high-pressure common flow path (common rail)) through the overlap between the multiple inlet slots in the valve shaft according to this disclosure.

[0065] Figure 19This is a front view showing an example of a high-pressure liquid fuel supply line constituting a liquid fuel supply system according to this disclosure.

[0066] Figure 20 yes Figure 19 A three-dimensional image.

[0067] Figure 21 This is a perspective view showing the structure of a connection for leak detection in a high-pressure liquid fuel supply pipeline according to the present disclosure.

[0068] Figure 22 yes Figure 21 An exploded perspective view of the connection part used for leak detection.

[0069] Figure 23 This is an exploded view of a connection for leak detection in a high-pressure liquid fuel supply pipeline according to this disclosure.

[0070] Figure 24 From Figure 22 The view is taken from direction IV and is used to illustrate the structure of the connection part of the leak detection block.

[0071] Figure 25 It is along Figure 23 It is a cross-sectional view along the VV line, and a view used to illustrate the structure of the annular space connection of the leak detection block.

[0072] Figure 26 It is shown Figure 23 A cross-sectional view of the connection status of the leak detection connector in the middle.

[0073] Figure 27 It is along Figure 26 It is a sectional view along line VI-VI, and is a view used to illustrate the connection state of the annular space connecting groove and the construction of the separator insertion hole.

[0074] Figure 28 It shows how to insert the separator. Figure 27 The view shown illustrates the insertion of two separators into the holes to detect the state of leakage.

[0075] Figure 29 This is a perspective view showing the overall structure of a high-pressure liquid fuel supply pipeline, in which the block common rail according to this disclosure is applied.

[0076] Figure 30 yes Figure 29 A plan view of a portion of the block-type common rail system.

[0077] Figure 31 Based on Figure 30The view is a horizontal cross-sectional view taken from the center of the main fuel line, and is a view showing the construction and connection status of the block common rail main fuel line.

[0078] Figure 32 This is a perspective view showing the connection status of the main fuel line of the block common rail according to this disclosure.

[0079] Figure 33 This is a perspective view showing the connection state of the block-type common track annular space according to the present disclosure.

[0080] Figure 34 This is a view showing the construction of the connection between the connecting flange of the high-pressure inlet pipe of the block common rail according to the present disclosure and the upstream flange of the high-pressure block.

[0081] Figure 35 It is along Figure 30 The sectional view of line VII-VII, and is shown Figure 34 A view showing the state in which the flanges are connected.

[0082] Figure 36 This shows the state where the flange is separated. Figure 37 The view.

[0083] Figure 37 It is shown Figure 30 A view showing the structure of the connection between the high-pressure block and the jump block in a block-type common rail system.

[0084] Figure 38 It is along Figure 30 A cross-sectional view of lines VIII-VIII, showing the separated state. Figure 37 The diagram shows a cross-sectional view of the connection between the high-pressure block and the jump block of the block-type common rail.

[0085] Figure 39 This indicates that it is in a connected state. Figure 38 A sectional view of the connecting part.

[0086] Figure 40 It is along Figure 30 The view is a cross-sectional view along line IX-IX, and is a view showing the shape of the annular space inside the main fuel line and the high-pressure block.

[0087] Figure 41 It is along Figure 40 The view is a cross-sectional view along line XI-XI, and is a view showing the connection shape of the annular space inside the high-pressure block.

[0088] Figure 42 This is a perspective view showing the structure of the connection between the downstream flange of the jump block and the upstream flange of the high-pressure block in the block-type common rail according to the present disclosure.

[0089] Figure 43 It is along Figure 30 A cross-sectional view of line XX, and is shown Figure 42 A view showing the connection state of the two flanges.

[0090] Figure 44 It indicates that it is in a separated state. Figure 43 A view of the two flanges.

[0091] Figure 45 The block-type common rail according to this disclosure is shown, and is a partial plan view and front view.

[0092] Figure 46 It is along Figure 45 The view is a cross-sectional view along line XII-XII, and shows the structure of the main fuel line and the annular space connecting groove formed in the block-shaped body part on one side of the jump block.

[0093] Figure 47 It is along Figure 45 The view is a cross-sectional view along line XIII-XIII, and shows the structure of the main fuel line and the annular space connecting groove formed inside the block-shaped body on the other side of the jump block.

[0094] Figure 48 It is along Figure 45 The view is a cross-sectional view along line XIV-XIV, and shows the structure for connecting the upper annular space connecting groove and the lower annular space connecting groove formed inside the block-shaped body portion on one side of the jump block.

[0095] Figure 49 It is along Figure 45 The view is a cross-sectional view along line XV-XV, and shows the structure for connecting the upper annular space connecting groove and the lower annular space connecting groove formed inside the block-shaped body on the other side of the jumper block.

[0096] Figure 50 It is along Figure 45 A sectional view of line XVI-XVI, and is used for illustration. Figure 48 and Figure 49 A view of the structure in which the two vertical connecting holes are again connected to the separator insertion hole.

[0097] Figure 51 It is along Figure 45 The horizontal sectional view along line XVII-XVII is a view showing the connection structure of the lower annular space and the separator insertion hole of the block common rail.

[0098] Figure 52 This is a perspective view showing a jumper-type common rail according to the present disclosure.

[0099] Figure 53 yes Figure 52 The front view.

[0100] Figure 54 This is a view illustrating the construction of the high-pressure block and flange of the jumper in the jumper type common rail according to this disclosure.

[0101] Figure 55 It is a sectional view along line XVIII-XVIII of the same view, showing Figure 53 The state of connection between the high-pressure block and the flange of the jumper pipe.

[0102] Figure 56 It indicates that it is in a separated state. Figure 53 A view of the high-pressure block and flange of the jumper tube shown.

[0103] Figure 57 This is a view used to illustrate leak detection in a high-pressure liquid fuel supply line including a block common rail according to this disclosure.

[0104] Figure 58 This is a view used to illustrate leak detection in a high-pressure liquid fuel supply line including a jump-pipe common rail according to this disclosure.

[0105] Figure 59 This is a view used to illustrate leak detection in a high-pressure liquid fuel supply line including a straight common rail according to this disclosure. Detailed Implementation

[0106] The following refers to the attached diagram. Figures 2 to 59 The following will describe in detail specific embodiments of the liquid fuel supply system and vessel of this disclosure having the above-described features.

[0107] [Liquid fuel supply system and ship construction]

[0108] Figures 2 to 5 A liquid fuel supply system and a vessel according to this disclosure are shown, wherein Figure 2 This is a view showing the construction of the liquid fuel pressurization unit and its operating oil and fuel system. Figure 3 This is a view showing the structure of an engine and a ship equipped with a liquid fuel supply system. Figure 4 This is a perspective view showing the appearance of the liquid fuel pressurization unit. Figure 5 This is a view showing the appearance of the liquid fuel pressurization unit from another direction, and the appearance has been treated to be transparent.

[0109] Reference Figure 2 The liquid fuel supply system disclosed herein includes: a liquid fuel pressurization unit (or liquid fuel compression unit) 100, a low-pressure hydraulic pump 23, and a stepper motor 40.

[0110] The liquid fuel pressurization unit 100 is a device that operates a pressurization plunger according to the supply of low-pressure operating oil, pressurizes the low-pressure liquid fuel by the pressurization plunger to increase the pressure, and then delivers the liquid fuel toward the engine cylinder.

[0111] The low-pressure hydraulic pump 23 is a pump with an integrated motor 22 that operates by current applied by an inverter 21, etc. It compresses the operating oil to a low pressure (e.g., about 350 bar) and discharges it through the motor 22. The discharged low-pressure operating oil is supplied to the liquid fuel pressurization unit 100 through the working fluid supply line 24.

[0112] Stepper motor 40 is used to operate a valve that controls the flow of operating oil supplied to the pressurized plunger.

[0113] Low-pressure (e.g., about 10 bar) liquid fuel supplied from the low-pressure liquid fuel pump 31 on one side of the aforementioned liquid fuel tank 30 is introduced into the liquid fuel pressurization unit 100 via the low-pressure delivery pipe 32. By operating the pressurization plunger of the liquid fuel pressurization unit 100, the low-pressure liquid fuel is pressurized to the high pressure (e.g., about 600 bar) required by the engine cylinder (more specifically, common rail) and supplied toward the engine cylinder.

[0114] Next, Figure 3 The following is schematically shown: a liquid fuel supply system is installed in a ship, wherein the ship’s body is divided into several layers of space by multiple decks below the upper deck, and each of these layers is separated into different compartments by partition walls.

[0115] Liquid fuel tanks 30 for storing liquid fuels (such as methanol) are typically located in cargo holds with a double bottom structure, and the engine room may be located in a stern hold isolated from the cargo holds.

[0116] In the engine structure 6 located in the engine compartment, a liquid fuel pressurization unit 100, a low-pressure hydraulic pump 23, and an electric motor 22, according to the liquid fuel supply system of this disclosure, are installed. High-pressure liquid fuel discharged from the liquid fuel pressurization unit 100 is conveyed along the high-pressure liquid fuel inlet line 50 toward the cylinders. The high-pressure liquid fuel conveyed from the high-pressure liquid fuel inlet line 50 is distributed to each cylinder in the common rail 60.

[0117] In addition, a low-pressure liquid fuel pump 31 is provided on one side of the liquid fuel tank 30. A low-pressure delivery pipe 32 connects the low-pressure liquid fuel pump 31 and the liquid fuel pressurization unit 100 in the engine room. The low-pressure liquid fuel pump 31 is used to supply low-pressure (e.g., about 7 bar) liquid fuel. A low-pressure double-layer pipe, which is cheaper and lighter than the high-pressure delivery pipe, can be used as the low-pressure delivery pipe 32.

[0118] The low-pressure hydraulic pump 23 supplies low-pressure operating oil from the operating oil supply source to the liquid fuel pressurization unit 100. Engine oil, which is used as engine lubricant, can be used as the low-pressure operating oil. When engine oil is used as the low-pressure operating oil, it can be supplied from the oil outlet pipe 24a, which is drawn from the oil passage in the engine block. In this case, a separate facility such as an operating oil tank is not required, and the engine itself becomes the operating oil supply source.

[0119] The low-pressure hydraulic pump 23 is used to compress the operating oil to a low pressure (e.g., about 350 bar) and supply this low-pressure operating oil. Because the low-pressure hydraulic pump 23 has a small displacement and small size compared to the displacement (e.g., 650 bar) of high-pressure liquid fuel pumps in related technologies, it can be installed in the engine compartment or directly on the engine structure. Therefore, even if the low-pressure hydraulic pump 23 is directly installed on the engine, it will not occupy much space in the engine compartment, and most maintenance work on the liquid fuel supply system can be easily performed within the engine compartment.

[0120] Next, refer to Figures 4 to 5 The liquid fuel pressurization unit 100 may be provided with a valve housing 210 that forms part of the operating oil control unit 200, and a pump housing 510 that forms part of the piston pump unit 500.

[0121] The piston pump unit 500 is used to pressurize low-pressure liquid fuel to high pressure and discharge the liquid fuel by operating a piston under the pressure of operating oil supplied by the low-pressure hydraulic pump 23.

[0122] The operating oil control unit 200 performs control operations for supplying and discharging low-pressure operating oil to operate the piston pump unit 500.

[0123] On one side of the operating oil control unit 200 are provided: a stepper motor 40 for valve actuation; an operating oil inlet port 200a through which low-pressure operating oil from the low-pressure hydraulic pump 23 is introduced; and an operating oil return port 200b for returning the operating oil discharged after the piston pump unit 500 is operated to the supply source.

[0124] In addition, a liquid fuel inlet port 500a and a liquid fuel outlet port 500b are provided on one side of the piston pump unit 500. Low-pressure liquid fuel from the low-pressure delivery pipe 32 is introduced through the liquid fuel inlet port 500a, and the liquid fuel outlet port 500b is used to discharge the compressed high-pressure liquid fuel from the piston pump unit 500 toward the cylinder, that is, to the high-pressure liquid fuel inlet pipe 50.

[0125] Reference Figure 5In the piston pump unit 500 of the liquid fuel pressurization unit 100, multiple plunger pump sections P500 are arranged in parallel, and the operating oil control unit 200 includes multiple valve sections V300, which are used for supplying and discharging low-pressure operating oil to the multiple plunger pump sections P500 arranged in parallel.

[0126] In this case, multiple valve sections V300 are configured to operate sequentially with equal cycles, so that multiple plunger pump sections P500 pressurize and discharge liquid fuel sequentially with equal cycles.

[0127] The piston pump unit 500 according to this disclosure can be in the form of a set of plunger pump section P500 and valve section V300. Furthermore, as... Figure 5 The example shown can be configured with multiple groups (e.g., such as...). Figure 5 It is in the form of four groups) plunger pump section P500 and valve section V300.

[0128] Multiple valve sections V300 can all be formed on a single valve shaft 300 rotated by a stepper motor 40. In other words, multiple valve sections V300 can be formed on the circumference of a single valve shaft 300 by maintaining an axial spacing corresponding to the spacing of multiple plunger pump sections P500. Accordingly, multiple valve sections V300 can be simply arranged on a single valve shaft 300.

[0129] [Structure of the liquid fuel pressurization unit 100]

[0130] Next, the structure of the liquid fuel pressurization unit 100 will be described in detail. The structure of the liquid fuel pressurization unit 100 specifically includes: the structure of the operating oil control unit 200 and its valve section V300, the structure of the piston pump unit 500 and its plunger pump section P500, and the pressure balancing structure for controlling the cylinder 212 and the valve shaft 300.

[0131] Figures 6 to 7 It is along Figure 5 The cross-sectional view along line II shows the structure of the operating oil control unit 200 and valve section V300, as well as the piston pump unit 500 and plunger pump section P500 of the liquid fuel pressurization unit according to this disclosure. Figure 6 The diagram illustrates the process of pressurizing low-pressure liquid fuel to high pressure and discharging it via pump operation of a liquid fuel pressurization unit. Figure 7 The image shows a view illustrating the process of refilling low-pressure liquid fuel into the high-pressure chamber C2 of the liquid fuel pressurization unit.

[0132] Reference Figures 6 to 7The operating oil control unit 200 includes a control cylinder 212 formed inside the valve housing 210, a rotary valve shaft 300 for controlling the flow direction of the operating oil inside the control cylinder 212, and a valve portion V300 formed on the valve shaft 300.

[0133] The plunger pump section P500 includes a low-pressure cylinder 502 and a low-pressure chamber C1, a high-pressure cylinder 504 and a high-pressure chamber C2, a pressurizing plunger 600, and a high-pressure liquid fuel discharge flow path 514, which is the outlet of the high-pressure chamber C2.

[0134] The low-pressure cylinder 502 has a large diameter, and the diameter of the high-pressure cylinder 504 is smaller than that of the low-pressure cylinder 502.

[0135] The pressurizing plunger 600 is equipped with: a low-pressure piston 610 with a large diameter that moves in the low-pressure cylinder 502 at one end; a high-pressure piston 620 with a small diameter that moves in the high-pressure cylinder 504 at the opposite side; and a rod portion 630 that connects the low-pressure piston 610 and the high-pressure piston 620 into one unit.

[0136] The pressurizing plunger 600 performs pressurization through the diameter difference between the low-pressure piston 610 and the high-pressure piston 620.

[0137] An operating oil supply port 214 is formed between the control cylinder 212 and the low-pressure chamber C1.

[0138] When operating oil is introduced into the low-pressure chamber C1 from one side of the control cylinder 212 through the operating oil supply port 214, it pushes the low-pressure piston 610, and the pressurizing plunger 600 moves in the compression direction (liquid fuel discharge direction). As the pressurizing plunger 600 moves in the compression direction, the high-pressure piston 620 pressurizes the liquid fuel in the high-pressure chamber C2. The pressurized liquid fuel is supplied to the aforementioned high-pressure liquid fuel inlet pipe 50 through the high-pressure liquid fuel discharge flow path 514.

[0139] When the pressurization of the liquid fuel is complete, the pressurizing plunger 600 returns to the release direction (liquid fuel filling direction) under the restoring force of the compression spring 640. Therefore, the low-pressure piston 610 pushes out the operating oil present in the low-pressure chamber C1 and discharges it to the operating oil supply port 214. Simultaneously, the high-pressure chamber C2 is refilled with low-pressure liquid fuel.

[0140] The valve section V300 will be described in more detail below.

[0141] The valve section V300 is formed on the outer periphery of the valve shaft 300 and meets the operating oil supply port 214 according to the rotation of the valve shaft 300.

[0142] The valve section V300 is equipped with an inlet groove 304 and an outlet groove 306.

[0143] At the center of the valve shaft 300, an operating oil supply flow path 302 is formed along the axial direction. An operating oil distribution flow path 303 is formed radially through the operating oil supply flow path 302 to the inlet groove 304.

[0144] Therefore, when the inlet tank 304 meets and connects with the operating oil supply port 214, the operating oil supplied from the operating oil supply flow path 302 is introduced into the inlet tank 304 along the operating oil distribution flow path 303, and enters the low-pressure chamber C1 from the inlet tank 304 through the operating oil supply port 214.

[0145] The outlet groove 306 communicates with the discharge recess 312 provided in the valve housing 210, and the discharge recess 312 is connected to the discharge flow path 314.

[0146] In fact, to discharge the operating oil introduced into the outlet groove 306, as will be described in detail later, a connecting groove 308 is also included, formed axially from the outlet groove 306, and a discharge groove 310 is recessed in the form of an annular groove on the outer periphery of the valve shaft 300 at one end of the connecting groove 308. The discharge groove 310 and the discharge recess 312 are always in communication.

[0147] Therefore, when the valve shaft 300 rotates and the outlet groove 306 meets the operating oil supply port 214, the operating oil in the low-pressure chamber C1 flows out through the operating oil supply port 214 to the outlet groove 306. Furthermore, after passing sequentially from the outlet groove 306 through the connecting groove 308 and the discharge groove 310, the operating oil flows to the discharge recess 312 and is then discharged through the discharge flow path 314.

[0148] like Figure 6 and Figure 7 As shown, in this disclosure, a total of two inlet grooves 304 are formed in a symmetrical shape on the left and right sides of the cross-section of the valve shaft 300. A total of two outlet grooves 306 are formed in a symmetrical shape on the left and right sides in a direction orthogonal to the inlet grooves 304. That is, two inlet grooves 304 and two outlet grooves 306 are formed respectively.

[0149] Therefore, when the valve shaft 300 performs one revolution, the two inlet slots 304 and the two outlet slots 306 alternately encounter the operating oil supply port 214. Thus, for each revolution of the valve shaft 300, a total of two operating oil supply / discharge operations are performed. Accordingly, the pressure plunger 600 performs a total of two liquid fuel pressure (discharge) operations.

[0150] Thus, if the valve shaft 300 performs two liquid fuel pressurization strokes per revolution, the time interval for high-pressure liquid fuel discharge is shortened. This allows for the maintenance of a uniform peak pressure with small pressure fluctuations within the shared discharge flow path 516 of the common rail 60 and the high-pressure chamber C2, and also reduces pressure pulsation. Consequently, liquid fuel can be stably supplied to the fuel injection valve of the cylinder with small pressure fluctuations.

[0151] Next, the construction of the pressure balance flow path will be described in detail.

[0152] The pressure-balanced flow path ensures that the pressure of the operating oil acting on the valve shaft 300 is evenly distributed on the reverse side of the operating oil supply port 214, thereby preventing vibration and uneven wear of the valve shaft 300, achieving operational stability of the operating oil control unit 200, and preventing vibration, noise, and shortened service life.

[0153] Reference Figures 6 to 7 In the valve housing 210, when the center of the cross-section of the valve shaft 300 is taken as a reference, a reverse port 214a communicating with the control cylinder 212 is formed on the radial reverse side of the operating oil supply port 214.

[0154] The reverse port 214a is made of a groove with the same diameter as the operating oil supply port 214 and provides a symmetrical space through which operating oil can be introduced even on the reverse side of the operating oil supply port 214.

[0155] The reverse port 214a is connected to the low-pressure chamber C1 and the pressure balance flow path 220.

[0156] A pressure balancing flow path 220 can be formed in the valve housing 210 to bypass the control cylinder 212. As shown, this can be constructed by a first balancing flow path 220-1 connected to the low-pressure chamber C1 and a second balancing flow path 220-2 connected to the first balancing flow path 220-1 and connected to the reverse port 214a. This can be achieved by pushing a drill bit inward from the inlet side of the low-pressure cylinder 502 inside the valve housing 210 to form the first balancing flow path 220-1, and by pushing a drill bit into the valve housing 210 from the outside to form the second balancing flow path 220-2. The inlet (drill entry hole) of the second balancing flow path 220-2 is closed by the plug 222.

[0157] like Figure 6 As shown, when the inlet slot 304 meets the operating oil supply port 214 (i.e., during the compression stroke), and as Figure 7As shown, when the outlet tank 306 meets the operating oil supply port 214, the operating oil pressure of the low-pressure chamber C1, which is controlled by the operating oil control unit 200, also acts simultaneously and equally on the reverse port 214a on the reverse side of the operating oil supply port 214.

[0158] Therefore, since the operating oil acts on both sides of the valve shaft 300 at the same pressure, the valve shaft 300 under load can achieve radial load balance.

[0159] In this disclosure, the pressure balance flow path 220 is described as a structure formed by drilling through, for example, the valve housing 210, but the low-pressure chamber C1 and the reverse port 214a can also be connected by a pipe or hose that bypasses the outside of the valve housing 210.

[0160] Next, the construction of the plunger pump section P500 of the piston pump unit 500 will be described in more detail.

[0161] Previously, the plunger pump section P500 was described as including: a low-pressure cylinder 502 with a large diameter filled with operating oil; a high-pressure cylinder 504 with a small diameter for pressurizing low-pressure liquid fuel; a pressurizing plunger 600 with a low-pressure piston 610 and a high-pressure piston 620 formed on both sides; and a high-pressure liquid fuel discharge flow path 514 for conveying high-pressure liquid fuel pressurized by the high-pressure piston 620 and whose pressure is increased toward the cylinder.

[0162] In addition, a separate cylinder bushing 520 forming the high-pressure cylinder 504 can be inserted and installed in the pump housing 510.

[0163] The cylinder bushing 520 is used to form the high-pressure section cylinder 504 so that it can be easily replaced in case of wear of the high-pressure section cylinder 504, and so that the formation of the liquid fuel supply flow path or the installation of the pressurizing plunger 600, etc., can be easily performed, as described below.

[0164] Multiple low-pressure liquid fuel distribution holes 522 are formed radially through this cylinder liner 520. Low-pressure liquid fuel inlet grooves 512, which contact the multiple low-pressure liquid fuel distribution holes 522, are formed in the form of annular grooves in the pump housing 510.

[0165] Low-pressure liquid fuel supplied from low-pressure liquid fuel pump 31 is introduced into low-pressure liquid fuel inlet tank 512 and enters low-pressure liquid fuel distribution hole 522.

[0166] An inlet groove 622 is formed on the outer periphery of the high-pressure piston 620, which contacts and communicates with the low-pressure liquid fuel distribution hole 522, and a plurality of distribution channels 624 are formed in the radial direction from the inlet groove 622 toward the axial center of the high-pressure piston 620.

[0167] Furthermore, an inlet channel 626, which connects the inner ends of multiple distribution channels 624, is formed through one end along the axial direction of the high-pressure piston 620.

[0168] Therefore, the low-pressure liquid fuel introduced into the low-pressure liquid fuel distribution hole 522 can pass through the inlet groove 622, the distribution channel 624 and the inlet channel 626 in sequence and be filled into the high-pressure chamber C2.

[0169] At the outlet of the high-pressure liquid fuel discharge flow path 514, a common discharge flow path 516 is formed. The high-pressure liquid fuel discharged from the high-pressure liquid fuel discharge flow path 514 is collected in the common discharge flow path 516 and supplied to the high-pressure liquid fuel inlet pipe 50 connected thereto.

[0170] A compression spring 640 is installed inside the low-pressure piston 610. When the liquid fuel in the high-pressure chamber C2 is discharged and the pressure in the high-pressure chamber C2 is released, the compression spring 640, under the action of the spring restoring force, pushes the low-pressure piston 610 in the opposite direction to compression, and discharges the operating oil from the low-pressure chamber C1. In this case, the low-pressure liquid fuel is refilled into the high-pressure chamber C2 through the low-pressure liquid fuel inlet channel 512 -> inlet channel 622 -> distribution channel 624 -> inlet channel 626.

[0171] Meanwhile, a first check valve 660 can be installed in the low-pressure liquid fuel inlet channel 626, and a second check valve 670 can be installed in the high-pressure liquid fuel discharge flow path 514.

[0172] The first check valve 660 always closes the inlet passage 626, thereby preventing backflow of liquid fuel in the high-pressure chamber C2 when the pressurizing plunger 600 moves in the compression direction to increase the pressure in the high-pressure chamber C2 to the set pressure. Furthermore, when the high-pressure liquid fuel is discharged and the pressure inside the high-pressure chamber C2 is released, it is opened by the pressure of the low-pressure liquid fuel acting on the inlet passage 626, allowing the low-pressure liquid fuel to be refilled into the high-pressure chamber C2.

[0173] The second check valve 670 always closes the high-pressure liquid fuel discharge flow path 514. Therefore, while preventing the high-pressure liquid fuel on the common discharge flow path 516 side, which is subjected to the pressure of the common rail, from flowing back into the high-pressure chamber C2, the high-pressure chamber C2 is sealed, allowing the low-pressure liquid fuel to fill the high-pressure chamber C2 with a predetermined amount as much as possible.

[0174] When the pressure of the liquid fuel in the high-pressure chamber C2 is increased to a set pressure (e.g., 650 bar) by the pressurization operation of the pressurizing plunger 600, the second check valve 670 operates in the direction of opening the high-pressure liquid fuel discharge flow path 514, so that the pressurized high-pressure liquid fuel can be discharged.

[0175] In this disclosure, the low-pressure cylinder 502 can be formed on one side of the valve housing 210, and the high-pressure cylinder 504 can be formed on one side of the pump housing 510. By dividing and forming the low-pressure cylinder 502 and the high-pressure cylinder 504 in the valve housing 210 and the pump housing 510 respectively, the machining of the low-pressure cylinder 502 and the high-pressure cylinder 504 is easy, and the assembly of the cylinder bushing 520 and the pressurizing plunger 600 can be easily performed.

[0176] Reference Figure 6 This will describe the compression and discharge strokes of the pressurized plunger 600.

[0177] As the valve shaft 300 rotates, when the inlet groove 304 meets and connects with the operating oil supply port 214, the operating oil introduced from the operating oil supply flow path 302 is introduced into the inlet groove 304 along the operating oil distribution flow path 303. Furthermore, the operating oil enters the low-pressure chamber C1 from the inlet groove 304 through the operating oil supply port 214, the reverse port 214a, and the pressure balance flow path 220.

[0178] The operating oil entering the low-pressure chamber C1 pushes the low-pressure piston 610, thereby causing the pressure plunger 600 to move in the compression direction ( Figure 6 The piston (left side) moves, causing the high-pressure piston 620 to pressurize the low-pressure liquid fuel filled in the high-pressure chamber C2.

[0179] In this case, the first check valve 660 maintains the inlet passage 626 closed by the compression pressure of the high-pressure chamber C2.

[0180] When the pressure in the high-pressure chamber C2 reaches the set pressure due to the pressurization operation of the high-pressure piston 620, the second check valve 670 opens. Therefore, the pressurized liquid fuel is discharged through the high-pressure liquid fuel discharge flow path 514 to the common discharge flow path 516.

[0181] like Figure 6 As shown, when the high-pressure section piston 620 moves to the end and the liquid fuel discharge is completed, the pressure in the high-pressure chamber C2 is released.

[0182] Therefore, as Figure 7 As shown, the first check valve 660 is opened by the pressure of the low-pressure liquid fuel introduced through the inlet channel 626, so that the low-pressure liquid fuel is refilled into the high-pressure chamber C2.

[0183] Simultaneously, the pressurized plunger 600, through the restoring force of the compression spring 640, moves along the liquid fuel filling direction (or, the operating oil discharge direction). Figure 6 (Move to the right of the middle)

[0184] Then, as Figure 7 As shown, the operating oil in the low-pressure chamber C1 flows out to the outlet groove 306 of the valve shaft 300 through the operating oil supply port 214, the pressure balance flow path 220 and the reverse port 214a, and then flows out from the outlet groove 306 to the discharge groove 310 through the connecting groove 308, and then is discharged from the discharge groove 310 through the discharge recess 312 to the discharge flow path 314.

[0185] As described above, with the two inlet slots 304 and the two outlet slots 306, this pressurization and filling stroke is performed twice for every revolution of the valve shaft 300.

[0186] exist Figure 8 The image shows a view illustrating the opening / closing changes of the valve section V300 and the displacement of the pressure plunger 600 according to the rotation of the valve shaft 300.

[0187] As described above, two inlet grooves 304 and two outlet grooves 306 are respectively formed on the orthogonal sides of the valve shaft 300.

[0188] Therefore, when the valve shaft 300 performs one rotation, the two inlet slots 304 and the two outlet slots 306 alternately encounter the operating oil supply port 214. Thus, for each rotation of the valve shaft 300, a total of two operating oil supply / discharge operations and two liquid fuel pressurization / filling operations are performed. Therefore, the discharge time interval of the high-pressure liquid fuel is shortened, allowing a uniform peak pressure with small pressure fluctuations to be maintained within the shared discharge flow path 516 of the common rail 60 and the high-pressure chamber C2.

[0189] [Multiple parallel liquid fuel pressurization units 100]

[0190] Next, an embodiment of multiple plunger pump sections P500 and valve sections V300 installed in parallel will be described.

[0191] exist Figures 9 to 18 The image shows a view used to illustrate this type of multiple parallel liquid fuel pressurization units.

[0192] exist Figure 9 The image shows a three-dimensional cross-sectional view. Figure 10 The plan is shown in the middle. Figure 11 In the middle, it is shown that along Figure 5 The sectional view of line II-II, in Figure 12 In the middle, it is shown that along Figure 5 The sectional view of line III-III, in Figure 13 The form of valve shaft 300 is shown in the figure, and in Figure 13 The image shows a valve section V300 and an operating oil inlet trough 320.

[0193] Reference Figures 9 to 14 The valve shaft 300 has a configuration in which multiple valve sections V300 are formed by maintaining a certain interval in the axial direction. Corresponding to the multiple valve sections V300, multiple plunger pump sections P500 are arranged in parallel. In this way, by designing a configuration in which all valves for controlling multiple plunger pump sections P500 are located in one valve shaft 300, the overall structure of the liquid fuel pressurization unit 100, including the valve device, becomes simple and can be constructed compactly.

[0194] In this embodiment, a configuration with four valve sections V300 and four plunger pump sections P500 is described, but the number can be increased or decreased as needed.

[0195] As described above, a valve section V300 has two inlet slots 304 and two outlet slots 306. Each inlet slot 304 and outlet slot 306 is connected by a connecting slot 308.

[0196] Furthermore, an operating oil inlet groove 320 is formed on the outer periphery of the valve shaft 300 for supplying operating oil to multiple valve sections V300. An operating oil supply hole 322 is formed radially through the operating oil inlet groove 320. The operating oil supply hole 322 is configured to communicate with an operating oil supply flow path 302 that is formed along the axial center of the valve shaft 300.

[0197] like Figure 12 As shown, operating oil supplied from the low-pressure hydraulic pump 23 enters the connecting flow path 204 through the operating oil inlet port 200a formed in the valve housing 210. The operating oil entering the connecting flow path 204 is introduced into the operating oil inlet groove 320 formed in the valve shaft 300 and moves circumferentially, while simultaneously moving radially inward through a plurality of operating oil supply holes 322 to be introduced into the operating oil supply flow path 302.

[0198] Although the operating oil supply flow path 302 is relatively long along the axial center of the valve shaft 300, it is different from the operating oil distribution flow path 303 on the valve section V300 side (see reference). Figures 6 to 7 The oil is connected and thus supplied to the inlet tank 304 via the operation oil distribution flow path 303.

[0199] At the same time, refer to Figures 9 to 10A liquid fuel supply channel 512a is formed in the pump housing 510 for supplying low-pressure liquid fuel from the liquid fuel inlet port 500a. The low-pressure liquid fuel introduced into the liquid fuel inlet port 500a is supplied through the liquid fuel supply channel 512a to the low-pressure liquid fuel inlet groove 512 and the low-pressure liquid fuel distribution hole 522 of each plunger pump section P500.

[0200] Furthermore, in the pump housing 510, for each valve section V300 and plunger pump section P500, the aforementioned operating oil supply port 214 and high-pressure liquid fuel discharge flow path 514 are respectively formed.

[0201] The high-pressure liquid fuel discharge flow path 514 of each plunger pump section P500 is connected to a common discharge flow path 516. Therefore, the high-pressure liquid fuel discharged through the high-pressure liquid fuel discharge flow path 514 of each plunger pump section P500 merges in the common discharge flow path 516 and is then sent to the high-pressure liquid fuel inlet line 50 and common rail 60 through the liquid fuel discharge port 500b.

[0202] Next, multiple valve sections V300 are formed such that they have a phase difference of equal angle (equal interval) with each other in the rotation direction of valve shaft 300.

[0203] In other words, such as Figure 13 and Figure 15 As shown, when the rotation direction of the valve shaft 300 is taken as a reference, the valve section V300 facing the operating oil supply port 214 and the other valve section V300 immediately following it have a phase difference of 360° / 2N in the circumferential direction (where "N" is the number of valve sections V300).

[0204] For example, if there are four valve sections V300 (V300-#1 to V300-#4), as shown in the embodiment in the attached figure, since two inlet slots 304 and outlet slots 306 are formed in one valve section V300, 2N=8, therefore the phase difference between the preceding valve section V300 and the immediately following valve section V300 becomes 45° (=360° / 8) (refer to...). Figure 15 ).

[0205] exist Figure 15 The example shown has a 45° phase difference between the first valve section V300-#1 and the fourth valve section V300-#4.

[0206] However, it is sufficient for the multiple valve sections V300 to have non-overlapping phase differences, and it is not necessary for them to have corresponding phase differences sequentially according to the order in which they are formed on the valve shaft 300.

[0207] For example, when the first valve section V300-#1 is used as a reference, any valve section other than the first valve section V300-#1 (e.g., V300-#3) is given a 45° phase difference, and relative to this valve section V300-#3, any other valve section other than the two valve sections V300-#1 and #3 (e.g., V300-#4) is given a 45° phase difference, and relative to valve section V300-#4, the remaining valve section V300-#2 is given a 45° phase difference. In this case, the pressurization / discharge of liquid fuel is performed in the order of V300-#1→V300-#3→V300-#4→V300-#2.

[0208] Thus, a valve section V300 has two inlet slots 304 and an outlet slot 306, and when multiple valve sections V300 and plunger pump sections P500 are configured, the multiple valve sections V300 are arranged with a phase difference of 360° / 2N from each other. Therefore, each time the valve shaft 300 rotates once, 2N operating oil supply / discharge operations are performed at equal intervals, and accordingly, 2N liquid fuel pressurization / discharge operations are performed at equal intervals. According to this configuration, the discharge interval of high-pressure liquid fuel can be shortened, and accordingly, the pressure fluctuation of liquid fuel is even smaller, and a uniform peak pressure can be maintained within the common discharge flow path 516 at the rear end of the common rail 60 and the high-pressure chamber C2, and pressure pulsation can be reduced. Therefore, liquid fuel with a uniform and stable peak pressure can be supplied to the fuel injection valve of the cylinder.

[0209] Next, in Figure 16 The image shows an overlapping view used to illustrate the inlet slot 304.

[0210] In the configuration of multiple valve sections V300, the overlap of the inlet grooves 304 is arranged such that at the point in time when the tail end 304-b of the inlet groove 304-L (shown in solid line) of any valve section V300 is in the process of supplying operating oil through communication with the operating oil supply port 214, based on the fact that the rotation direction of the valve shaft 300 has not deviated from the operating oil supply port 214, the front end 304-a of the inlet groove 304-T (shown in dashed line) of the next valve section V300 meets the operating oil supply port 214 to begin the supply of operating oil.

[0211] In this case, the angle at which the tail end 304-b of the inlet groove 304-L of the preceding valve section V300 overlaps with the operating oil supply port 214 is an overlap angle (β°). That is, the two inlet grooves 304 of the preceding valve section V300 and the following valve section V300 are simultaneously opened to the operating oil supply port 214 for a period of time.

[0212] In other words, at the point in time when the front end 304-a of the inlet groove 304-T of any subsequent valve section V300 meets the operating oil supply port 214 to begin supplying operating oil, the rear end 304-b of the inlet groove 304-L of the adjacent preceding valve section V300 is in a state of continuing to supply operating oil by communicating with the operating oil supply port 214 at an overlap angle (β°).

[0213] exist Figure 17 In the graph, which serves as a guide for setting the range of this overlap angle (β°), experiments show that the overlap angle (β°) can be set to a range of 5° to 25°.

[0214] Within this range (5° to 25°), the overlap angle (β°) can be set by increasing or decreasing the width dimension of each inlet slot 304 in the rotation direction.

[0215] Furthermore, in determining the overlap range, for example, the operating oil supply port 214 is designed to have a diameter such that operating oil can be introduced and discharged at a flow rate and volume suitable for the pressurization capacity, operating cycle, and speed of the pressurizing plunger 600. Therefore, the width of the inlet groove 304 in the rotational direction is designed to have a dimension suitable for the diameter of the operating oil supply port 214.

[0216] Furthermore, it should be considered that as the diameter of the operating oil supply port 214 increases, the width of the inlet groove 304 also increases, thus requiring an increase in the final diameter of the valve shaft 300, thereby increasing the overall size of the liquid fuel pressurization unit 100. Additionally, it is necessary to design the system considering that if the size and overlap of the inlet groove 304 become excessively large, the strength of the valve shaft 300 may weaken.

[0217] exist Figure 18 The diagram shows a view of the pressure changes in the common rail 60 and the common discharge flow path 516 when the configuration described above is applied.

[0218] In other words, when multiple valve sections V300 and plunger pump sections P500 are used, it can be seen that when the overlap angle (β°) of the inlet groove 304 is 5° to 25°, the peak pressure remains flat in the common rail 60 and the common discharge flow path 516.

[0219] "Peak pressure remains flat" means that the liquid fuel pressure within the common rail 60 and the common exhaust flow path 516 is continuously and uniformly maintained at the maximum pressure (with small pressure fluctuations). Therefore, a liquid fuel pressurization unit 100 can be implemented that maintains a uniform peak pressure with smaller pressure fluctuations within the common rail 60 and the common exhaust flow path 516, reduces pressure pulsation, and allows for a stable supply of liquid fuel to the cylinder with minimal pressure fluctuations via a fuel injection valve.

[0220] In the foregoing, the liquid fuel pressurization unit 100 is described as a unit for pressurizing liquid "fuel," but it is clear that the liquid fuel pressurization unit 100 according to this disclosure can be used not only as a unit for pressurizing liquid "fuel," but also as a unit for pressurizing liquid "control oil" or "sealing oil." As control oil or sealing oil, hydraulic oil (hydraulic operating oil), lubricating oil, etc., mainly used in hydraulic or lubrication systems, can be mentioned. For example, hydraulic oil or lubricating oil can be pressurized to high pressure by the liquid fuel pressurization unit 100 of this disclosure and supplied to the operating part as control oil (or pilot oil) or operating oil (working oil), to the sealing part as sealing oil, or to the lubrication part as lubricating oil.

[0221] [Liquid Fuel Supply Line - Example 1]

[0222] Next, embodiments of the liquid fuel supply line (high-pressure liquid fuel supply line) constituting the liquid fuel supply system according to the present disclosure will be described.

[0223] Figures 19 to 26 This is a view showing a liquid fuel supply line according to a first embodiment of the present disclosure.

[0224] First of all, Figure 19 The image shows a front view of an example of a liquid fuel supply pipeline constituting a liquid fuel supply system, and... Figure 20 The image shown is a 3D model.

[0225] Reference Figures 19 to 20 The liquid fuel supply line disclosed herein is constructed by including a high-pressure liquid fuel inlet line 50, a common rail 60, and an outlet line 70. The high-pressure liquid fuel inlet line 50 is a high-pressure double-layered pipe connected from the liquid fuel pressurization unit 100 toward the engine cylinder. The common rail 60 is connected to the high-pressure liquid fuel inlet line 50 and is used to supply high-pressure liquid fuel to the engine cylinder. The outlet line 70 is a high-pressure double-layered pipe connected to the outlet of the common rail 60.

[0226] In this embodiment, a configuration is disclosed in which a high-pressure liquid fuel inlet pipe 50 is divided into a first inlet pipe 50a on the upstream side in the liquid fuel flow direction and a second inlet pipe 50b on the downstream side, and the separated first inlet pipe 50a and second inlet pipe 50b are connected by a leak detection connector 700.

[0227] The leak detection connector 700 is a connector for attaching to / removing the leak detection separator 850, which will be described later according to this disclosure. The leak detection connector 700 remains installed during operation (except during maintenance or replacement).

[0228] The leak detection connection 700 is configured to connect the first inlet pipe 50a and the annular space 54a located between the first inlet pipe 50a and the second inlet pipe 50b, and is also configured such that the separator 850 for inserting the leak detection sensor 860 (described later) can be attached / removed in this configuration, while disconnecting the annular space 54a during leak detection.

[0229] A safety valve unit 80 can be installed in the discharge line 70. Furthermore, the discharge line 70 can be divided into a first discharge line 70a and a second discharge line 70b based on the safety valve unit 80, and a leak detection connection 700 can be installed at the separate parts.

[0230] The safety valve unit 80 functions to regulate pressure by discharging liquid fuel in the event of excessive pressure, while maintaining a constant pressure in the common rail 60. Additionally, the safety valve unit 80 can be used as needed (e.g., in emergencies or during maintenance).

[0231] Reference Figure 20 The high-pressure liquid fuel inlet pipe 50 and outlet pipe 70 have a high-pressure double-layer pipe structure and are configured to have an inner pipe 52 forming a main fuel pipe 52a inside and an outer pipe 54 forming an annular space 54a outside the inner pipe 52, the annular space 54a being a space in the radial direction.

[0232] High-pressure (e.g., 650 bar) liquid fuel discharged from the liquid fuel pressurization unit 100 is transported through the main fuel line 52a of the high-pressure liquid fuel inlet line 50.

[0233] Inert gas can flow through the annular space 54a. A leak alarm tank (not shown) is provided at the downstream end of the discharge line 70, which is used to recover fuel leaked into the annular space and to display or notify whether a leak has occurred.

[0234] Next, Figures 21 to 28 This is used to describe the connection part 700 for leak detection, in which... Figure 21 This is a view showing a three-dimensional diagram. Figure 22 An exploded 3D view is shown. Figure 23 Showing the anatomical view, Figure 24 Showing from Figure 22 The view from direction IV. Figure 25 Show along Figure 23 A cross-sectional view of line VV. Figure 26 It shows Figure 23 A cross-sectional view of the connection part for leak detection in the connected state. Figure 27 It shows along Figure 26 A sectional view of line VI-VI, and Figure 28It shows the separator being inserted into Figure 27 A view showing the state of the two separators inserted into the holes.

[0235] Reference Figures 21 to 25 The leak detection connection 700 includes a connecting flange 710 with a double-walled (or double-walled) structure connected to the first inlet pipe 50a, and a leak detection block 750 connected to the second inlet pipe 50b.

[0236] The connecting flange 710 and the leak detection block 750 are fastened to abut against each other by fastening devices such as bolts 704 / nuts 754.

[0237] The connecting flange 710 includes: an inner joint 712 connected to the inner tube 52 of the first inlet pipe 50a; an outer joint 714 connected to the outer tube 54 of the first inlet pipe 50a; and a connecting surface 720 facing and abutting against the leak detection block 750.

[0238] In the inner joint 712, a main fuel line connection hole 712a is formed at its center, which is connected to the main fuel line 52a of the first inlet line 50a.

[0239] This internal joint 712 is welded together to form an inner tube 52 that abuts against the first inlet pipe 50a.

[0240] In the outer joint 714, an annular groove 714a is formed that connects to the annular space 54a of the first inlet pipe 50a, and is welded together to form an outer pipe 54 that abuts against the first inlet pipe 50a.

[0241] In this case, the separate pipe 54-1 can be assembled and connected between the outer joint 714 and the outer pipe 54, and between the outer pipe 54 and the outer joint 764.

[0242] The split tube 54-1 is a component used to ensure the gap interval, at which the welding torch can be placed between the end of the outer tube 54 and the outer joints 714, 764.

[0243] Meanwhile, an annular groove 730 is formed in the connecting surface 720 of the connecting flange 710. The annular groove 730 is formed by maintaining a distance from the main fuel line connecting hole 712a in the radial direction.

[0244] The annular groove 730 and the annular groove 714a are connected by a plurality of through holes 732. Therefore, the plurality of through holes 732 are interconnected through the annular groove 730.

[0245] An inner sealing groove 722 and an outer sealing groove 724 may be formed in the connecting surface 720.

[0246] An inner sealing groove 722 is formed between the annular groove 730 and the inner joint 712. An outer sealing groove 724 is formed on the outside of the annular groove 730.

[0247] In the example shown in the attached drawings, the inner sealing groove 722 and the outer sealing groove 724 are formed in the connecting flange 710, but they can also be formed in the connecting surface 770 of the leak detection block 750.

[0248] By inserting the seal 722a into each of the inner sealing groove 722 and the outer sealing groove 724, the airtightness between the two connecting surfaces 720 and 770 can be maintained.

[0249] The leak detection block 750 includes: an inner joint 762 connected to the inner tube 52 of the second inlet pipe 50b; an outer joint 764 connected to the outer tube 54 of the second inlet pipe 50b; and a connecting surface 770 facing and abutting against the connecting flange 710.

[0250] In the inner joint 762, a main fuel line connection hole 762a is formed at its center, which is connected to the main fuel line 52a of the second inlet line 50b.

[0251] This internal joint 762 is welded together to form the inner tube 52 that abuts against the second inlet pipe 50b.

[0252] In the outer joint 764, an annular groove 764a is formed that connects to the annular space 54a of the second inlet pipe 50b, and is welded together to form an outer pipe 54 that abuts against the second inlet pipe 50b.

[0253] In the connecting surface 770 of the leakage detection block 750, a first annular space connecting groove 782, which communicates with the annular groove 730 of the connecting flange 710, is formed to a certain depth in the axial direction (longitudinal direction) to the body.

[0254] In the annular groove 764a of the leak detection block 750, the second annular space connecting groove 792, which is connected to the annular space 54a of the second inlet pipe 50b, is formed to a certain depth in the axial direction (longitudinal direction) to the body.

[0255] Reference Figures 24 to 25 The first annular space connecting groove 782 and the second annular space connecting groove 792 are formed to a certain depth in the axial direction on two sides with opposite diameters.

[0256] Furthermore, in each of the first annular space connecting groove 782 and the second annular space connecting groove 792, the cross-sectional shape is made into an arc concentric with the main fuel line connecting hole 762a. This ensures that the cross-sectional area of ​​the annular space is larger than that of the circular hole without increasing the size of the connecting surface 770.

[0257] Furthermore, an annular groove 780 is formed in the connecting surface 770. The annular groove 780 faces and communicates with the annular groove 730 of the connecting flange 710.

[0258] The first annular spatial connecting groove 782 is formed inside the annular groove 780. Therefore, the first annular spatial connecting groove 782 remains in communication with the annular groove 780.

[0259] Reference Figure 26 When the connecting surface 720 of the connecting flange 710 and the connecting surface 770 of the leakage detection block 750 are connected to abut against each other, the annular groove 730 of the connecting flange 710 and the annular groove 780 of the leakage detection block 750 are in communication with each other.

[0260] Therefore, through the connection of the two annular grooves 730 and 780, the multiple through holes 732 of the connecting flange 710 and the first annular space connecting groove 782 of the leakage detection block 750 are connected to each other.

[0261] The first annular space connecting groove 782 and the second annular space connecting groove 792 are connected to each other through the separator insertion holes 810 and 820, which will be described later.

[0262] exist Figure 27 (along) Figure 26 The connection structure of the first annular space connecting groove 782 and the second annular space connecting groove 792 is shown in the sectional view along line VI-VI.

[0263] Reference Figure 26 and Figure 27 The separator insertion holes 810 and 820 are formed by penetrating from the outer periphery of the leak detection block 750 toward the interior of the body.

[0264] The first separator insertion hole 810 is formed to connect one end of the first annular space connecting groove 782 and the second annular space connecting groove 792 across the width direction. Therefore, one end of each of the first annular space connecting groove 782 and the second annular space connecting groove 792 is connected to each other through the first separator insertion hole 810.

[0265] The second separator insertion hole 820 is formed to connect to the other end of the first annular space connecting groove 782 and the second annular space connecting groove 792 in the width direction. Therefore, the opposite ends of the first annular space connecting groove 782 and the second annular space connecting groove 792 are connected to each other through the second separator insertion hole 820.

[0266] Therefore, the inner end of the first partition insertion hole 810 and the middle part of the second partition insertion hole 820 are in a state of communication with each other through the first annular space connecting groove 782. Similarly, the inner end of the second partition insertion hole 820 and the middle part of the first partition insertion hole 810 are in a state of communication with each other through the second annular space connecting groove 792.

[0267] The first connecting hole 830 spans the end of the first separator insertion hole 810 and connects the middle of the second separator insertion hole 820. The first connecting hole 830 passes through the arc-shaped first annular space connecting groove 782 in the lateral direction, thereby making the first annular space connecting groove 782 more reliably connected to the first separator insertion hole 810 and the second separator insertion hole 820.

[0268] Furthermore, the second connecting hole 840 spans the end of the second separator insertion hole 820 and connects the middle of the first separator insertion hole 810. The second connecting hole 840 passes through the arc-shaped second annular space connecting groove 792 in the lateral direction, thereby making the second annular space connecting groove 792 more reliably connected to the second separator insertion hole 820 and the first separator insertion hole 810.

[0269] The entrances to the first separator insertion hole 810, the second separator insertion hole 820, the first connecting hole 830, and the second connecting hole 840 can be closed by plug 802 and plug 804, respectively.

[0270] Next, refer to Figure 28 During leak detection, the separator 850 is inserted into the first separator insertion hole 810 and the second separator insertion hole 820. In this case, firstly, the plug 802 is removed.

[0271] The separator 850 ensures that the sensor (probe) 860 insertion hole 854 formed at the center of the separator 850 is in communication with only one of the two annular space connection slots (782 or 792), while closing the communication connection between the first annular space connection slot 782 and the second annular space connection slot 792.

[0272] That is, such as Figure 28As shown, in the separator 850 inserted into the first separator insertion hole 810, its head 852 closes the first separator insertion hole 810 to close the communication between one end of the first annular space connection groove 782 and the second annular space connection groove 792. Furthermore, the end surface (or end face) of the head 852, which is the insertion end of the separator 850, is exposed and communicates with the first annular space connection groove 782 and the first communication hole 830. Therefore, when the leak detection sensor 860 is inserted into the sensor insertion hole 854 formed in the center of the separator 850, the probe portion of the leak detection sensor 860 can detect leaked fuel in the first annular space connection groove 782.

[0273] Similarly, in the separator 850 inserted into the second separator insertion hole 820, its head 852 closes the second separator insertion hole 820 to close the communication between the other ends of the second annular space connecting groove 792 and the first annular space connecting groove 782. Furthermore, the end surface of the head 852, which is the insertion end of the separator 850, is exposed in the second annular space connecting groove 792 and the second communicating hole 840. Therefore, when the leak detection sensor 860 is inserted into the sensor insertion hole 854 formed in the center of the separator 850, the probe portion of the leak detection sensor 860 can detect leaked fuel in the second annular space connecting groove 792.

[0274] Therefore, when the leak detection sensor 860 is inserted into the sensor insertion hole 854 formed in the center of the separator 850, the probe portion of the leak detection sensor 860 can detect the leaking fuel in the second annular space connection groove 792.

[0275] If it is desired to detect the leakage status of the annular space on only one side of the first annular space connection groove 782 (i.e., the side of the first inlet pipe 50a), then only the correct separator 850 is inserted into the first separator insertion hole 810, and a separately manufactured dummy separator can be inserted into the second separator insertion hole 820.

[0276] Conversely, if it is desired to detect the leakage status of the annular space on only one side of the second annular space connection groove 792 (i.e., the side of the second inlet pipe 50b), then only the correct separator 850 is inserted into the second separator insertion hole 820, and a separately manufactured virtual separator can be inserted into the first separator insertion hole 810.

[0277] In this way, by always providing a leak detection connection 700 in the high-pressure liquid fuel inlet line 50, leaks can be easily detected at any time before operation or during the testing steps, simply by disassembling the plug 802 from each separator insertion hole 810 and 820 and inserting it into the separator 850, without a separate and complicated process.

[0278] At the same time, Figures 17 to 18 In the embodiment shown, it can be configured to have only a first separator insertion hole 810 and no second separator insertion hole 820.

[0279] In this configuration, the first annular space connecting groove 782 / first communicating hole 830 and the second annular space connecting groove 792 / second communicating hole 840 are connected only through the first separator insertion hole 810. Therefore, by inserting the separator 850 into the first separator insertion hole 810 and inserting the leak detection sensor 860 into the separator 850, it is possible to detect whether a leak has occurred in the first annular space connecting groove 782, which is located on the upstream side of the annular space in the direction of liquid fuel flow.

[0280] Therefore, if it is necessary to detect all leaks in the annular space on both the upstream and downstream sides in a single leak detection block 750, then a leak detection block 750 having both a first separator insertion hole 810 and a second separator insertion hole 820 formed therein is used. Conversely, if it is only necessary to detect leaks in the annular space on the upstream side, a leak detection block 750 having only a first separator insertion hole 810 formed can also be used.

[0281] [Liquid Fuel Supply Line - Example 2]

[0282] Figures 29 to 51 This is a view used to illustrate another embodiment of a liquid fuel supply line according to the present disclosure, in which the common rail 60 is configured as a block common rail 60a and a leak detection structure is applied to the corresponding block common rail 60a.

[0283] exist Figure 29 The image shows an embodiment of a liquid fuel supply line for a liquid fuel supply system according to the present disclosure, and... Figure 30 The diagram shows a plan view of the main components of the common rail.

[0284] Reference Figures 29 to 30 The liquid fuel supply line disclosed herein is constructed by a high-pressure liquid fuel inlet line 50 comprising a high-pressure double-layered pipe, a block common rail 60a connected to the high-pressure liquid fuel inlet line 50 and used to supply high-pressure liquid fuel to the engine cylinder, and an outlet line 70 made of a high-pressure double-layered pipe connected to the outlet of the block common rail 60a.

[0285] As described above, the high-pressure liquid fuel inlet line 50 and outlet line 70 are provided with an inner pipe 52 forming a main fuel line 52a at the center, and an outer pipe 54 maintaining an annular space 54a outside the inner pipe 52.

[0286] The block common rail 60a disclosed herein is configured with a plurality of high-pressure blocks 1000 and a jumper block 2000. The plurality of high-pressure blocks 1000 are arranged in parallel with the engine cylinder and installed on the engine cylinder block. The jumper block 2000 has a solid block-shaped body and is connected between adjacent high-pressure blocks 1000.

[0287] The high-pressure block 1000 has an engine-side flange portion 1001 on one side of the main body, and an upstream side flange portion 1002 and a downstream side flange portion 1003 on the two sides opposite to the engine-side flange portion 1001, respectively.

[0288] The jump block 2000 has a block-shaped body portion 2001, an upstream side flange portion 2002 connected to the downstream side flange portion 1003 of the high-voltage block 1000 at one end of the block-shaped body portion 2001, and a downstream side flange portion 2003 connected to the upstream side flange portion 1002 of the adjacent high-voltage block 1000 at the other end of the block-shaped body portion 2001.

[0289] Furthermore, a leak detection separator attachment / removal part 2004 is formed in the middle of the block-shaped body part 2001 of the jump block 2000.

[0290] exist Figure 31 In the middle, it is shown that based on Figure 30 A horizontal cross-sectional view taken from the center of the main fuel line, and in Figure 32 The image shows a view of the construction and connection status of the main fuel line.

[0291] Reference Figures 31 to 32 The main fuel line connection hole 1100-1 is continuously formed in a branching manner towards the engine block, and simultaneously connects the cross-sectional center of the high pressure block 1000 and the jump block 2000.

[0292] The main fuel line connection hole 1100-1 is equipped with a first main fuel line connection hole 1110, a second main fuel line connection hole 1120, a third main fuel line connection hole 1130 and a fourth main fuel line connection hole 2100.

[0293] The first to third main fuel line connection holes 1110 to 1130 are liquid fuel channels located in the high-pressure block 1000, and the fourth main fuel line connection hole 2100 is a liquid fuel channel located in the jump block 2000.

[0294] The first main fuel line connection hole 1110 of the high pressure block 1000 is formed by penetrating straight through one side of the upstream flange 1002 toward the center of the body.

[0295] The second main fuel line connection hole 1120 is formed by penetrating straight through one side of the downstream flange 1003 toward the center of the body.

[0296] The first main fuel line connection hole 1110 and the second main fuel line connection hole 1120 are joined at the center of the body.

[0297] Furthermore, a third main fuel line connection hole 1130 is formed by penetrating straight through from one side of the engine side flange portion 1001 toward the center of the body. This third main fuel line connection hole 1130 meets and communicates with the junction of the first main fuel line connection hole 1110 and the second main fuel line connection hole 1120.

[0298] The fourth main fuel line connection hole 2100 of the jump block 2000 is connected through the upstream flange 2002, the block body 2001 and the downstream flange 2003 of the jump block 2000.

[0299] For penetration formation (e.g., drilling), the fourth main fuel line connection hole 2100 can be configured such that the upstream main line connection hole 2100a and the downstream main line connection hole 2100b meet at the midpoint of the longitudinal direction of the body (see [reference]). Figures 31 to 32 (as shown in the form).

[0300] For this purpose, the upstream main pipeline connection hole 2100a is formed in a straight line penetrating from the middle portion of the upstream flange portion 2002 to the block body portion 2001. The inlet (upstream end) of the upstream main pipeline connection hole 2100a is connected to the outlet (downstream end) of the second main fuel pipeline connection hole 1120 formed in the downstream flange portion 1003 of the high-pressure block 1000.

[0301] The downstream main pipeline connection hole 2100b is formed in a straight line penetrating from the downstream flange portion 2003 to the middle portion of the block body portion 2001. This downstream main pipeline connection hole 2100b communicates with the upstream main pipeline connection hole 2100a at the midpoint of the block body portion 2001. Furthermore, the outlet of the downstream main pipeline connection hole 2100b is connected to the inlet of the first main fuel pipeline connection hole 1110 formed in the upstream flange portion 1002 of the adjacent downstream high-pressure block 1000.

[0302] According to the configuration described above, high-pressure liquid fuel introduced towards the block common rail 60a via the main fuel line 52a of the high-pressure liquid fuel inlet line 50 fills the main fuel line connection holes 1100-1, which penetrate multiple high-pressure blocks 1000 and multiple jump blocks 2000, at the pressure required by the cylinder. Subsequently, according to the combustion stroke of each cylinder, it is supplied to the injector of each cylinder through the third main fuel line connection hole 1130 of each high-pressure block 1000.

[0303] Next, in Figure 33 The image shows a view of the connection state of the annular space of the block-type common rail 60a.

[0304] Reference Figure 33 According to this disclosure, the annular space connection groove 1100-2 is formed to penetrate and connect the high-pressure block 1000 and the jumper block 2000 throughout the entire length, while being connected in parallel with the main fuel line connection hole 1100-1 and maintaining a horizontal position relative to the ground without any height difference.

[0305] The annular space connecting groove 1100-2 is equipped with an upper annular space connecting groove 1100-2a and a lower annular space connecting groove 1100-2b.

[0306] The upper annular space connection groove 1100-2a is penetrated to form a continuous connection between the high pressure block 1000 and the jumper block 2000 along the entire length at the upper part of the main fuel line connection hole 1100-1.

[0307] The lower annular space connection groove 1100-2b is penetrated to form a continuous connection between the high-pressure block 1000 and the jumper block 2000 along the entire length at the lower part of the main fuel line connection hole 1100-1.

[0308] The upper annular space connecting groove 1100-2a and the lower annular space connecting groove 1100-2b are kept horizontal with no height difference relative to the ground in all sections, while maintaining a state of parallel connection with the main fuel pipeline connecting hole 1100-1.

[0309] Thus, when designing a block-type common rail 60a including jump blocks 2000 as the common rail 60, the annular space connection groove 1100-2 can be formed through penetration work inside the solid jump blocks 2000. Therefore, the annular space connection groove 1100-2 can be easily formed horizontally on all sections of the jump blocks 2000. When the annular space connection groove 1100-2 is kept horizontal in a manner without height differences (such as gradients or steps), fuel leaking into the annular space connection groove 1100-2 can flow smoothly and be discharged.

[0310] The annular space connecting groove 1100-2 in the section of the high-pressure block 1000 is provided with a first upper annular space connecting groove 1232 and a first lower annular space connecting groove 1234, which are formed in a straight line penetrating from one side of the upstream flange portion 1002 toward the center of the body.

[0311] Furthermore, a second upper annular space connecting groove 1332 and a second lower annular space connecting groove 1334 are provided, forming in a straight line from one side of the downstream flange portion 1003 toward the center of the body. Each of the second upper annular space connecting groove 1332 and the second lower annular space connecting groove 1334 engages with the first upper annular space connecting groove 1232 and the first lower annular space connecting groove 1234 respectively at the center of the high-pressure block 1000 body. At each engagement, an upper connecting hole 1410 and a lower connecting hole 1420, which will be described later, can be formed.

[0312] In addition, the annular space connecting groove 1100-2 in the section of the jump block 2000 is equipped with a third upper annular space connecting groove 2232 and a third lower annular space connecting groove 2234.

[0313] The third upper annular space connecting groove 2232 is equipped with an upstream upper annular space connecting groove 2232a and a downstream upper annular space connecting groove 2232b.

[0314] The annular space connecting groove 2232a on the upstream side is formed in a straight line from one side of the upstream flange portion 2002 to the midpoint of the block body portion 2001 (i.e., the separator attachment / removal portion 2004).

[0315] The annular space connecting groove 2232b on the downstream side is formed in a straight line from one side of the downstream flange 2003 to the midpoint of the block body 2001 (i.e., the separator attachment / removal part 2004).

[0316] The inlets of the upper annular space connecting groove 2232a and the lower annular space connecting groove 2234a on the upstream side are horizontally connected to the outlets of the second upper annular space connecting groove 1332 and the second lower annular space connecting groove 1334 of the downstream flange portion 1003 of the high-pressure block 1000 without any height difference.

[0317] In addition, the inlets of the downstream upper annular space connection groove 2232b and the downstream lower annular space connection groove 2234b are respectively horizontally connected to the first upper annular space connection groove 1232 and the first lower annular space connection groove 1234 of the upstream flange portion 1002 of the adjacent high-pressure block 1000 on the downstream side.

[0318] As described above, the upper annular space connecting groove 1100-2a and the lower annular space connecting groove 1100-2b of the annular space connecting groove 1100-2 are connected to each other at one or more points in a section between a high-pressure block 1000 and a jump block 2000.

[0319] In the embodiment shown in the accompanying drawings, they communicate with each other at a portion of the separator attachment / removal portion 2004 of the jump block 2000 (first point) and a portion of the annular grooves 1330 and 2230 of the downstream flange portion 1003 and the upstream flange portion 2002 of the high-pressure block 1000 (second point), which will be described later.

[0320] In the separator attachment / removal part 2004, the upper annular space connecting groove 2232a on the upstream side and the lower annular space connecting groove 2234a on the upstream side are connected in the vertical direction through the first vertical connecting hole 2330.

[0321] Additionally, at a point far from the first vertical connecting hole 2330, the downstream upper annular space connecting groove 2232b and the downstream lower annular space connecting groove 2234b are connected in the vertical direction through the second vertical connecting hole 2430.

[0322] Furthermore, the separator insertion hole 2500 is formed in a form that passes through and connects the first vertical connecting hole 2330 and the second vertical connecting hole 2430.

[0323] When the leak detection separator 850 is inserted into the separator insertion hole 2500, the second vertical connecting hole 2430 is closed by the head 852 of the separator 850, thus the connection between the first vertical connecting hole 2330 and the second vertical connecting hole 2430 is broken.

[0324] Meanwhile, one end of the separator 850 is exposed in the first vertical connecting hole 2330. Therefore, the leak detection sensor 860, inserted into the separator 850, can detect leaked fuel in the upstream upper annular space connecting groove 2232a and the upstream lower annular space connecting groove 2234a. This will be described in more detail later with reference to other accompanying drawings.

[0325] Next, Figures 34 to 36 The structure of the connection for connecting the block common rail 60a and the high-pressure liquid fuel inlet line 50 is shown, wherein Figure 34 A perspective view and a sectional view are shown. Figure 35 A cross-sectional view is shown in the connected state. Figure 36 A cross-sectional view in the separated state is shown. (See also...) Figures 31 to 33 .

[0326] Reference Figures 34 to 36 And refer to together Figures 31 to 33 The connecting flange 900 on one side of the high-pressure liquid fuel inlet pipe 50 includes an inner joint 912 connected to the inner pipe 52, an outer joint 914 connected to the outer pipe 54, and a connecting surface 920 facing and abutting the upstream flange 1002 of the high-pressure block 1000.

[0327] In the inner joint 912, a main fuel line connection hole 912a is formed in its center, which is connected to the main fuel line 52a of the high-pressure liquid fuel inlet line 50.

[0328] This internal joint 912 is welded together to form an inner tube 52 that abuts against the high-pressure liquid fuel inlet pipe 50.

[0329] In the outer joint 914, an annular groove 914a is formed that connects to the annular space 54a of the high-pressure liquid fuel inlet pipe 50, and is welded together to abut the outer pipe 54.

[0330] In the connecting surface 920 of the connecting flange 910, an annular groove 930 is formed by maintaining a spacing toward the outside in the radial direction of the main fuel line connecting hole 912a.

[0331] The annular groove 930 and the annular groove 914a are connected by a plurality of through holes 932. Therefore, the plurality of through holes 932 are interconnected through the annular groove 930.

[0332] In the connecting flange 900, a fastening hole 902 is formed for fastening to the upstream flange portion 1002 of the high-pressure block 1000.

[0333] Next, a first main fuel line connection hole 1110 is formed at the center of the upstream flange portion 1002 of the high-pressure block 1000. This first main fuel line connection hole 1110 is connected to the main fuel line connection hole 912a on the connecting flange 900 side.

[0334] Furthermore, an annular groove 1230 is formed in the connecting surface 1220 of the upstream flange portion 1002. The annular groove 1230 is formed by maintaining a distance from the radial direction of the first main fuel line connection hole 1110.

[0335] A first upper annular space connecting groove 1232 and a first lower annular space connecting groove 1234 are formed at the upper and lower parts of the annular groove 1230, respectively. Therefore, the first upper annular space connecting groove 1232 and the first lower annular space connecting groove 1234 are connected to each other at the annular groove 1230.

[0336] The annular groove 1230 also abuts against and communicates with the annular groove 930 of the connecting flange 900. Therefore, the through hole 932 of the connecting flange 900 communicates with the first upper annular space connecting groove 1232 and the first lower annular space connecting groove 1234 of the upstream flange portion 1002 through the annular groove 930 and the annular groove 1230.

[0337] The first upper annular space connecting groove 1232 and the first lower annular space connecting groove 1234 are kept horizontal relative to the ground and are connected in parallel with the first main fuel pipeline connecting hole 1110.

[0338] In the upstream flange portion 1002, a fastening hole 1202 is formed for fastening with the fastening hole 902 of the connecting flange 900. The fastening hole 902 of the connecting flange 900 and the fastening hole 1202 of the upstream flange portion 1002 are fastened by bolts 904.

[0339] An inner sealing groove 1222 and an outer sealing groove 1224 can be formed in the connecting surface 1220 of the upstream flange portion 1002. This is achieved by using the seal 1222a (see...) Figure 35 The space between the two connecting surfaces 920 and 1220 is sealed in each of the inner sealing groove 1222 and the outer sealing groove 1224.

[0340] Next, Figures 37 to 39 The structure of the connection between the high-voltage block 1000 and the jumper block 2000 of the block-type common rail 60a is shown, wherein Figure 37 A 3D view is shown. Figure 38 Anatomical views are shown. Figure 39 A cross-sectional view showing the connection status is shown. Please refer to the attached document for further details. Figures 31 to 33 .

[0341] Reference Figures 37 to 39 as well as Figures 31 to 33 In the downstream flange portion 1003 of the high-pressure block 1000, a second main fuel line connection hole 1120 is formed in its center. This second main fuel line connection hole 1120 connects to the first main fuel line connection hole 1110 on one side of the upstream flange portion 1002 inside the body of the high-pressure block 1000 (see [reference]). Figures 31 to 32 ).

[0342] Furthermore, in the connecting surface 1320 of the downstream flange portion 1003, an annular groove 1330 is formed by maintaining a distance toward the outside in the radial direction of the second main fuel line connecting hole 1120.

[0343] A second upper annular space connecting groove 1332 and a second lower annular space connecting groove 1334 are formed at the upper and lower parts of the annular groove 1330, respectively. Therefore, the second upper annular space connecting groove 1332 and the second lower annular space connecting groove 1334 are connected to each other at the annular groove 1330.

[0344] In the upstream flange portion 2002 of the jump block 2000, a fourth main fuel line connection hole 2100 is formed in its center. For example... Figures 31 to 32 As described above, since the fourth main fuel line connection hole 2100 extends only from the upstream flange portion 2002 to the separator attachment / removal portion 2004, it is specifically distinguished as "upstream main line connection hole 2100a".

[0345] This fourth main fuel line connection hole 2100 extends downstream from the upstream flange portion 2002 along the block-shaped body portion 2001 of the jump block 2000 to the separator attachment / removal portion 2004.

[0346] Furthermore, an annular groove 2230 is formed in the connecting surface 2220 of the upstream flange portion 2002 of the jump block 2000. The annular groove 2230 is formed by maintaining a distance outward in the radial direction of the fourth main fuel line connection hole 2100.

[0347] A third upper annular space connecting groove 2232 and a third lower annular space connecting groove 2234 are formed in the annular groove 2230. Therefore, the third upper annular space connecting groove 2232 and the third lower annular space connecting groove 2234 are connected to each other at the annular groove 2230.

[0348] like Figure 33 As described above, since the third upper annular space connecting groove 2232 of the upstream flange portion 2002 of the jump block 2000 only extends from the upstream flange portion 2002 to the separator attachment / removal portion 2004, it is specially distinguished as "upper annular space connecting groove 2232a", while the third lower annular space connecting groove 2234 is distinguished as "lower annular space connecting groove 2234a".

[0349] The annular groove 2230 also abuts against and communicates with the annular groove 1330 of the downstream flange portion 1003 of the high-pressure block 1000. Therefore, as Figures 37 to 39 As shown, the second upper annular space connecting groove 1332 and the second lower annular space connecting groove 1334 of the downstream flange portion 1003 of the high-pressure block 1000 are connected to the upstream upper annular space connecting groove 2232a and the upstream lower annular space connecting groove 2234a of the upstream flange portion 2002 of the jump block 2000 through annular groove 1330 and annular groove 2230.

[0350] The first upper annular space connecting groove 1232, the upstream side upper annular space connecting groove 2232a, the second lower annular space connecting groove 1334, and the upstream side lower annular space connecting groove 2234a are kept horizontal with no height difference relative to the ground, and are connected in parallel with the second main fuel pipeline connecting hole 1120 and the fourth main fuel pipeline connecting hole 2100.

[0351] Then, as Figure 39 As shown, since the second lower annular space connecting groove 1334 and the third lower annular space connecting groove 2234 (i.e., the upstream lower annular space connecting groove 2234a) are horizontally connected to each other in a manner without height difference (such as gradient or step), the leaked fuel can flow smoothly and be discharged without accumulating at the connection of the third lower annular space connecting groove 2234 (i.e., the upstream lower annular space connecting groove 2234a).

[0352] In addition, fastening holes 1302 and 2202 for fastening bolts 2204 are formed in the downstream flange portion 1003 of the high-pressure block 1000 and the upstream flange portion 2002 of the jump block 2000.

[0353] An inner sealing groove 1322 and an outer sealing groove 1324 can be formed in the connecting surface 1320 of the downstream flange portion 1003 of the high-pressure block 1000. By using the seal 1322a (see...) Figures 38 to 39 Inserted into each of these inner sealing grooves 1322 and outer sealing grooves 1324, the airtightness between the two connecting surfaces 1320 and 2220 can be maintained.

[0354] Next, Figures 40 to 41 This describes the connection state of the annular space formed by the engine-side flange 1001 facing the high-pressure block 1000, wherein Figure 40 It is along Figure 30 The cross-sectional view along line IX-IX shows the formation shape of the main fuel pipeline and annular space inside the high-pressure block 1000. Figure 41 It shows along Figure 40 A cross-sectional view along line XI-XI. (See also...) Figures 31 to 33 .

[0355] like Figures 40 to 41 and Figures 31 to 33 As shown, a third main fuel line connection hole 1130 is formed from the center of the engine side flange portion 1001 of the high-pressure block 1000 to the middle of the body. As described above, the third main fuel line connection hole 1130 communicates with the junction of the first main fuel line connection hole 1110 and the second main fuel line connection hole 1120 (see also...). Figure 31 ).

[0356] Furthermore, an upper connecting hole 1410 and a lower connecting hole 1420 are formed at the front of the high-pressure block 1000 body in a state of parallel connection with the third main fuel line connection hole 1130.

[0357] The upper connecting hole 1410 is connected through the point where it engages with the first upper annular space connecting groove 1232 and the second upper annular space connecting groove 1332 (while referring to...). Figure 33 ).

[0358] The lower connecting hole 1420 is connected through the point where it engages with the first lower annular space connecting groove 1234 and the second lower annular space connecting groove 1334 (see also...). Figure 33 ).

[0359] The engine-side high-pressure pipe 1500 can be connected to the third main fuel line connection hole 1130 of the high-pressure block 1000. An engine-side annular space 1430 is formed between the engine-side high-pressure pipe 1500 and the high-pressure block 1000. An upper extension hole 1412 is formed from the upper connecting hole 1410 to the engine-side annular space 1430, and a lower extension hole 1422 extends from the lower connecting hole 1420 to the engine-side annular space 1430.

[0360] Next, Figures 42 to 44 The structure of the connection between the downstream flange 2003 of the jump block 2000 and the upstream flange 1002 of the high-pressure block 1000 of the block common rail 60a according to the present disclosure is shown, wherein Figure 42 A 3D view is shown. Figure 43 It is along Figure 30 A cross-sectional view of line XX, showing the state of the two flanges connected. Figure 44 A cross-sectional view showing the two flanges partially separated is shown. (See also...) Figures 31 to 33 .

[0361] Reference Figures 42 to 44 The upstream flange 1002 of the high-pressure block 1000 is connected to the upper flange through... Figures 34 to 36 The upstream flange portion 1002 described is the same as the one described above, and its construction is also the same.

[0362] The downstream flange portion 2003 of the jump block 2000 is configured to have a similar shape to the jump block 2000. Figures 37 to 39 It has the same structure as the upstream flange portion 2002 described in the text.

[0363] That is, a fourth main fuel line connection hole 2100 is formed in the center of the downstream flange portion 2003 of the jump block 2000. For example... Figure 33 As shown, since the fourth main fuel line connection hole 2100 of the downstream flange portion 2003 extends only from the downstream flange portion 2003 to the separator attachment / removal portion 2004, it is specially distinguished as "downstream main line connection hole 2100b".

[0364] This downstream main pipeline connection hole 2100b (i.e., the fourth main fuel pipeline connection hole 2100) extends from the downstream flange portion 2003 to the separator attachment / removal portion 2004 in the upstream direction along the block body portion 2001 of the jump block 2000.

[0365] Furthermore, in the connecting surface 2220 of the downstream flange portion 2003 of the jump block 2000, an annular groove 2230 is formed by maintaining a distance from the fourth main fuel line connecting hole 2100 in the radial direction towards the outside.

[0366] A third upper annular space connecting groove 2232 and a third lower annular space connecting groove 2234 are formed at the upper and lower parts of the annular groove 2230, respectively. Therefore, the third upper annular space connecting groove 2232 and the third lower annular space connecting groove 2234 are connected to each other at the annular groove 2230.

[0367] like Figure 33 As shown, since the third upper annular space connecting groove 2232 of the downstream flange portion 2003 of the jump block 2000 only extends from the downstream flange portion 2003 to the separator attachment / removal portion 2004, it is specifically distinguished as "downstream upper annular space connecting groove 2232b". Similarly, the third lower annular space connecting groove 2234 is distinguished as "downstream lower annular space connecting groove 2234b".

[0368] In addition, the annular groove 2230 of the jump block 2000 abuts against the annular groove 1230 of the upstream flange portion 1002 of the high-pressure block 1000 and communicates with it.

[0369] Therefore, the downstream upper annular space connecting groove 2232b and the downstream lower annular space connecting groove 2234b of the downstream flange portion 2003 of the jump block 2000, and the first upper annular space connecting groove 1232 and the first lower annular space connecting groove 1234 of the upstream flange portion 1002 of the high-pressure block 1000 are connected to each other through the annular groove 2230 and the annular groove 1230 that abut against each other.

[0370] The downstream upper annular space connecting groove 2232b and the first upper annular space connecting groove 1232, as well as the downstream lower annular space connecting groove 2234b and the first lower annular space connecting groove 1234, remain horizontal with no height difference relative to the ground, and are connected in parallel with the first main fuel pipeline connecting hole 1110 and the fourth main fuel pipeline connecting hole 2100.

[0371] Accordingly, Figure 43 As shown, since the downstream lower annular space connecting groove 2234b of the jump block 2000 and the first lower annular space connecting groove 1234 of the high-pressure block 1000 are horizontally connected to each other in a manner without height difference (such as gradient or step), the leaked fuel can flow smoothly and be discharged.

[0372] Additionally, fastening holes 2202 and 1202 for fastening each other are formed in the downstream flange portion 2003 of the jump block 2000 and the upstream flange portion 1002 of the high-pressure block 1000.

[0373] Additionally, an inner sealing groove 1222 and an outer sealing groove 1224 can be formed in the connecting surface 1320 of the downstream flange portion 1003 of the high-pressure block 1000. By inserting the seal 1222a into each of these inner sealing grooves 1222 and outer sealing grooves 1224, the airtightness between the two connecting surfaces 2220 and 1220 can be maintained.

[0374] Next, Figures 45 to 50 This is a view used to illustrate the construction of the annular space connection groove formed in the separator attachment / removal part 2004 in the middle of the jump block 2000 and the block common rail 60a according to the present disclosure.

[0375] First of all, Figure 45 The diagram shows a plan view of the main components of the block common rail 60a according to this disclosure. (See also: [reference needed]) Figure 33 .

[0376] Reference Figure 45 As described above, the separator attachment / removal part 2004 for detecting whether fuel leakage into the annular space has occurred is provided in the middle of the jump block 2000.

[0377] The separator attachment / removal part 2004 is formed at the midpoint of the block-shaped body part 2001 of the jump block 2000.

[0378] In the block-shaped body section 2001, such as Figure 33 As shown, a fourth main fuel line connection hole 2100 is formed in the center, and a third upper annular space connection groove 2232 and a third lower annular space connection groove 2234 are formed at the upper and lower parts of the fourth main fuel line connection hole 2100.

[0379] In the separator attachment / removal part 2004, a separator insertion hole 2500 is formed (reference). Figures 50 to 51 This will be described in detail later, and the plug 2502 closes the entrance to the separator insertion hole 2500. During leak detection, after disconnecting the plug 2502, the separator 850 can be inserted into the separator insertion hole 2500.

[0380] In the separator attachment / removal section 2004 (see reference) Figure 33 The upstream upper annular space connecting groove 2232a and the downstream upper annular space connecting groove 2232 of the third upper annular space connecting groove 2232 are disconnected from each other. Similarly, the upstream lower annular space connecting groove 2234a and the downstream lower annular space connecting groove 2234b of the third lower annular space connecting groove 2234 are disconnected from each other.

[0381] In the separator attachment / removal section 2004, the disconnected upstream upper annular space connecting groove 2232a and downstream upper annular space connecting groove 2232b are connected to each other through the separator insertion hole 2500. Similarly, the disconnected upstream lower annular space connecting groove 2234a and downstream lower annular space connecting groove 2234b are connected to each other through the separator insertion hole 2500.

[0382] At the same time, through the separator insertion hole 2500, the upper annular space connecting groove 2232a and the lower annular space connecting groove 2234a on the upstream side are connected to each other, and the upper annular space connecting groove 2232b and the lower annular space connecting groove 2234b on the downstream side are also connected to each other.

[0383] When the separator 850 is inserted into the separator insertion hole 2500, the separator 850 closes the connection between the upstream annular space and the downstream annular space. That is, the connection between the upstream upper annular space connecting groove 2232a and the upstream lower annular space connecting groove 2234a and the downstream upper annular space connecting groove 2232b and the downstream lower annular space connecting groove 2234b is broken.

[0384] These matters will be described in detail with reference to the accompanying drawings.

[0385] exist Figure 46 (along) Figure 45 The cross-sectional view along line XII-XII shows the structure of the main fuel line and the annular space formed inside the block-shaped body 2001 on one side (upstream side) of the jump block 2000.

[0386] Reference Figures 45 to 46 (To be referenced together) Figure 33 In the block-shaped body portion 2001 located upstream of the jump block 2000, an upstream main pipeline connection hole 2100a is formed through the center, serving as the fourth main fuel pipeline connection hole 2100. Above the upstream main pipeline connection hole 2100a, an upstream upper annular space connection groove 2232a is formed in an arc shape, serving as the third upper annular space connection groove 2232. Below the upstream main pipeline connection hole 2100a, an upstream lower annular space connection groove 2234a is formed in an arc shape, serving as the third lower annular space connection groove 2234.

[0387] As described above, the upper annular space connecting groove 2232a and the lower annular space connecting groove 2234a on the upstream side are formed in a straight line from the upstream flange portion 2002 to the separator attachment / removal portion 2004 (see [link]). Figure 33 ).

[0388] exist Figure 47 (along) Figure 45The cross-sectional view along line XIII-XIII shows a view of the structure of the main fuel line and the annular space formed inside the block-shaped body 2001 on the other side (downstream side) of the jump block 2000.

[0389] Reference Figure 47 , Figure 33 and Figure 45 In the block-shaped body portion 2001 downstream of the jump block 2000, a downstream main pipeline connection hole 2100b is formed through the center, serving as the fourth main fuel pipeline connection hole 2100. An upper annular space connection groove 2232b is formed in an arc shape above the downstream main pipeline connection hole 2100b, serving as the third upper annular space connection groove 2232. A lower annular space connection groove 2234b is formed in an arc shape below the downstream main pipeline connection hole 2100b, serving as the third lower annular space connection groove 2234.

[0390] As described above, the downstream upper annular space connecting groove 2232b and the downstream lower annular space connecting groove 2234b are formed in a straight line from the downstream flange portion 2003 to the separator attachment / removal portion 2004 (see [link]). Figure 33 ).

[0391] exist Figure 48 (along) Figure 45 The cross-sectional view along line XIV-XIV shows the construction for connecting the upper annular space connecting groove 2232a on the upstream side and the lower annular space connecting groove 2234a on the upstream side.

[0392] Reference Figure 48 , Figure 33 and Figure 45 The upper connecting hole 2310 and the lower connecting hole 2320 pass through the ends (inner ends) of the upper annular space connecting groove 2232a and the lower annular space connecting groove 2234a on the upstream side, respectively.

[0393] In addition, the first vertical connecting hole 2330 passes through the ends (inner ends) of the upper connecting hole 2310 and the lower connecting hole 2320.

[0394] Therefore, the upper annular space connecting groove 2232a on the upstream side and the lower annular space connecting groove 2234a on the upstream side are connected to the first vertical connecting hole 2330 through the upper connecting hole 2310 and the lower connecting hole 2320, so as to communicate with each other.

[0395] The entrances to the upper connecting hole 2310 and the lower connecting hole 2320 are respectively closed by a threaded fastening plug 2302, and the entrance to the first vertical connecting hole 2330 is closed by a threaded fastening plug 2304.

[0396] exist Figure 49 (along) Figure 45 The cross-sectional view along line XV-XV shows the construction for connecting the upper annular space connecting groove 2232b on the downstream side and the lower annular space connecting groove 2234b on the downstream side.

[0397] Reference Figure 49 , Figure 33 and Figure 45 The upper connecting hole 2410 and the lower connecting hole 2420 pass through the ends of the lower annular space connecting groove 2232b and the lower annular space connecting groove 2234b on the downstream side, respectively.

[0398] Furthermore, the second vertical connecting hole 2430 passes through the ends (inner ends) of the upper connecting hole 2410 and the lower connecting hole 2420.

[0399] Therefore, the downstream upper annular space connecting groove 2232b and the downstream lower annular space connecting groove 2234b are connected to the second vertical connecting hole 2430 through the upper connecting hole 2410 and the lower connecting hole 2420, so as to communicate with each other.

[0400] Here, the first vertical connecting hole 2330 and the second vertical connecting hole 2430 are formed at points that are separated from each other along the longitudinal direction of the separator insertion hole 2500 (see...). Figure 33 and Figure 45 ).

[0401] Next, in Figure 50 (along) Figure 45 The sectional view along line XVI-XVI shows the illustration. Figure 48 and Figure 49 A view of the structure described in the figure, in which the first and second vertical connecting holes 2330 and 2430 are again connected to the separator insertion hole 2500.

[0402] Reference Figure 50 , Figure 33 and Figure 45 The separator insertion hole 2500 is formed to pass through the end (inner end) of the first vertical connecting hole 2330 and the second vertical connecting hole 2430.

[0403] The first vertical connecting hole 2330 and the second vertical connecting hole 2430 are connected to each other through the separator insertion hole 2500.

[0404] The inlet of the separator insertion hole 2500 is sealed by threaded fastening of a plug 2502. During leak detection, after loosening and disconnecting the plug 2502, the separator 850 can be inserted into the separator insertion hole 2500.

[0405] Next, in Figure 51 (along) Figure 45The horizontal sectional view along line XVII-XVII shows a view of the connection structure of the lower annular space and the separator insertion hole of the block common rail 60a.

[0406] We will refer to them together. Figure 51 , Figure 33 , Figure 45 and Figure 50 When the leak detection separator 850 is inserted into the separator insertion hole 2500, the head 852 of the separator 850 (see...) Figure 28 The middle part of the partition insertion hole 2500 is closed. Therefore, the connection between the first vertical connecting hole 2330 and the second vertical connecting hole 2430 is closed (or disconnected) by the head 852 of the partition 850. Thus, when the connection between the first vertical connecting hole 2330 and the second vertical connecting hole 2430 is closed, the connection between the upstream upper and lower annular space connecting grooves 2232a, 2234a and the downstream upper and lower annular space connecting grooves 2232b, 2234b is also closed.

[0407] Meanwhile, the end surface of the separator 850 (i.e., the end surface of the head 852) is exposed to the interior of the first vertical communication hole 2330. That is, it is exposed to the space at the inner end of the separator insertion hole 2500. Then, the sensor insertion hole 854, leading to the end surface of the head 852, communicates with the first vertical communication hole 2330. The sensor insertion hole 854 is disconnected from the second vertical communication hole 2430. Therefore, when the leak detection sensor 860 is inserted into the separator insertion hole 2500, the probe of the leak detection sensor 860 can be exposed to the space of the first vertical communication hole 2330. Here, when the first vertical connecting hole 2330 is connected to the upper connecting hole 2310 and the lower connecting hole 2320, the upper connecting hole 2310 is connected to the upper annular space connecting groove 2232a on the upstream side again, and the lower connecting hole 2320 is connected to the lower annular space connecting groove 2234a on the upstream side. Therefore, the probe of the leak detection sensor 860 can detect the fuel leaked into the annular space on the upstream side (i.e., the upper annular space connecting groove 2232a and the lower annular space connecting groove 2234a on the upstream side).

[0408] According to the liquid fuel supply pipeline and liquid fuel supply system of the block common rail 60a of this disclosure, which is configured in this way, the block common rail 60a has a structure in which the jump block 2000, which is provided with a separator attachment / removal part 2004, is always installed.

[0409] Therefore, leaks can be easily detected simply by disconnecting the plug 2502 of the separator insertion hole 2500 and inserting the separator 850, without a separate, complicated process, either during the test steps prior to operation or at any desired point during operation (e.g., when a leak alarm occurs in the leak alarm tank).

[0410] Furthermore, although the block-type common rail 60a of this disclosure is made in the form of connecting multiple high-pressure blocks 1000 and multiple jump blocks 2000, since the separator attachment / removal part 2004 is provided in each jump block 2000, leaks can be detected at several points of the common rail, and the leak point can be located accurately and easily.

[0411] Furthermore, the block-type common rail 60a of this disclosure is manufactured such that high-pressure blocks 1000 are connected to each other via solid block-type jumpers 2000 that are completely filled internally, and a main fuel line connection hole and an annular space connection groove are formed through the jumpers 2000. Therefore, the common rail can be configured without welds, thereby fundamentally eliminating the risk of defects or fuel leakage at welds. Furthermore, since the annular space connection grooves 1334 and 2234 between the high-pressure blocks and the jumpers can be connected without height differences (such as steps or gradients), fuel leaking into the annular space can flow and be discharged smoothly.

[0412] Furthermore, the high-pressure block 1000 and the jumping block 2000 that constitute the block common rail 60a are highly manufacturable because they can be manufactured after forging or casting by simply adding simple machining processes (e.g., penetration forming and surface finishing).

[0413] Furthermore, since the jump block 2000 is made of solid blocks, its length can be increased or decreased freely in design and manufacturing, so its application range is very wide. For example, it is even possible to easily realize an engine with a very narrow gap between the high-pressure blocks 1000 and the high-pressure blocks 1000.

[0414] Furthermore, since the block-type common rail 60a of this disclosure is made in the form of connecting multiple high-voltage blocks 1000 and multiple jump blocks 2000, it can be repaired or replaced by separating each high-voltage block 1000 as a unit or each jump block 2000 as a unit, thus making maintenance easy and reducing operating costs.

[0415] [Liquid Fuel Supply Line - Example 3]

[0416] Figures 52 to 56 This is another embodiment of the liquid fuel supply line according to the present disclosure, and specifically, it is a view illustrating an embodiment in which the common rail 60 is configured as a jump-pipe common rail 60b and a leak detection structure is applied to the corresponding jump-pipe common rail 60b.

[0417] exist Figure 52 The image shows a perspective view of the jump-tube common rail 60b. Figure 53 The front view is shown in the image. Figure 54The image shows an exploded perspective view of the flange 1003 of the high-voltage block 1000 and the leakage detection block 750 of the jumper pipe 3000. Figure 55 The diagram shows a cross-sectional view of the connection state (along...). Figure 55 (The sectional view of line XVIII-XVIII in the middle), and in Figure 56 The image shows a cross-sectional view of the separated state.

[0418] First, refer to Figures 52 to 54 The liquid fuel supply system according to this disclosure includes a high-pressure liquid fuel inlet line 50 (same as in Example 2). As described above, the high-pressure liquid fuel inlet line 50 consists of an inner pipe 52 that forms a main fuel line 52a inside and an outer pipe 54 that maintains an annular space 54a outside the inner pipe 52.

[0419] Additionally, a jump-pipe common rail 60b is provided as the common rail 60. The jump-pipe common rail 60b is connected to the high-pressure liquid fuel inlet line 50 and distributes the high-pressure liquid fuel to the engine cylinders.

[0420] Additionally, a discharge line 70 (same as in Example 2) is provided, which is a high-pressure double-layer pipe connected to the outlet of the jump-pipe common rail 60b.

[0421] The jump-pipe common rail 60b is equipped with a high-pressure block 1000 and a jump-pipe 3000.

[0422] The jumper pipe 3000 includes a double-layer bend pipe 3100 connected between adjacent high-pressure blocks 1000. The double-layer bend pipe 3100 consists of an inner pipe 3152 forming a main fuel line 3152a at the center and an outer pipe 3154 maintaining an annular space 3154a outside the inner pipe 3152.

[0423] At the upstream end of the double-bend pipe 3100, a leak detection block 750 is provided, and a leak detection separator 850 can be attached to or detached from the leak detection block 750. The leak detection block 750 and... Figures 21 to 28 The leak detection block 750 described in the text has the same form.

[0424] At the downstream end of the double-bend 3100, a connecting flange 900 is provided. This connecting flange 900 and... Figures 34 to 36 The connecting flange 900 described in the text has the same form.

[0425] A leakage detection block 750 located at the upstream end of the double-walled bend 3100 is connected to the downstream flange portion 1003 of the high-pressure block 1000. A connecting flange 900 located at the downstream end of the double-walled bend 3100 is connected to the upstream flange portion 1002 of the adjacent high-pressure block 1000 on the downstream side.

[0426] Figures 52 to 56 The high-voltage block 1000 shown is related to Figures 29 to 39 The high-voltage block 1000 described in the text is the same as the block.

[0427] In other words, the high-pressure block 1000 is provided with an engine side flange 1001 formed on one side of the body, an upstream side flange 1002 and a downstream side flange 1003 formed on both sides opposite to the engine side flange 1001, and a main fuel line connection hole 1100-1. The main fuel line connection hole 1100-1 is formed through the body so as to connect the upstream side flange 1002 and the downstream side flange 1003 by simultaneously branching through the center of the cross section of the body to the engine side flange 1000.

[0428] Figures 52 to 56 The downstream flange 1003 of the high-voltage block 1000 shown is configured to be with Figures 37 to 39 It has the same structure as the downstream side flange 1003 described in the text.

[0429] Therefore, an upper annular space connection groove 1100-2a and a lower annular space connection groove 1100-2b, which are formed through penetration and connected in parallel with the main fuel line connection hole 1100-1, are respectively provided at the upper and lower parts of the main fuel line connection hole 1100-1.

[0430] Similarly, Figures 52 to 56 The leak detection block 750 of the jumper 3000 shown has a similar function to... Figures 21 to 28 It has the same construction as the leak detection block 750 described in the text.

[0431] Therefore, the leak detection block 750 includes: a main fuel line connection hole 762a, which is connected at the center to the main fuel line connection hole 1100-1 of the high-pressure block 1000; a first annular space connection groove 782, which is formed to a certain depth to the body and faces the upper annular space connection groove 1100-2a and the lower annular space connection groove 1100-2b of the high-pressure block 1000; and a second annular space connection groove 792, which is formed to a certain depth to the body and communicates with the annular space 3154a on the diameter-reverse side of the first annular space connection groove 782.

[0432] Additionally, the leak detection block 750 is constructed by including a first separator insertion hole 810, a second separator insertion hole 820, a first connecting hole 830, and a second connecting hole 840, and is compatible with... Figures 27 to 28 The same as described herein. In each separator insertion hole 810 and 820, a fixed plug 802 is embedded. In the first connecting hole 830 and the second connecting hole 840, a fixed plug 804 is embedded.

[0433] After removing plug 804, by inserting the leak detection separator 850 into each of the first separator insertion hole 810 and the second separator insertion hole 820, the communication connection between the two ends of the first annular space connection groove 782 and the second annular space connection groove 792 is closed, and one end of each separator 850 is exposed to the interior of the first communication hole 830, which communicates only with the first annular space connection groove 782, and the interior of the second communication hole 840, which communicates only with the second annular space connection groove 792 (see also...). Figures 27 to 28 ).

[0434] When the leak detection sensor 860 is inserted into the central hole of the separator 850, the communication between one end of the first annular space connecting groove 782 and the second annular space connecting groove 792 in the separator 850 inserted into the first separator insertion hole 810 is closed by the head 852 of the first separator insertion hole 810. Furthermore, the insertion end of the separator 850 (i.e., the end surface of the head 852) is exposed to the first annular space connecting groove 782 and the first communicating hole 830. Therefore, when the leak detection sensor 860 is inserted into the central hole of the separator 850, the probe portion of the leak detection sensor 860 can detect leaked fuel in the first annular space connecting groove 782 and the first communicating hole 830. In this case, the first annular space connecting groove 782 communicates with the annular groove 1330 of the high-pressure block 1000, and the annular groove 1330 communicates with the second upper annular space connecting groove 1332 and the second lower annular space connecting groove 1334 of the high-pressure block 1000. Therefore, fuel leaking into the second upper annular space connecting groove 1332 and the second lower annular space connecting groove 1334 on one side of the high-pressure block 1000 can be detected by the leak detection sensor 860 (while referring to...). Figures 27 to 28 ).

[0435] Similarly, in the separator 850 inserted into the second separator insertion hole 820, the communication state of the other ends of the second annular space connecting groove 792 and the first annular space connecting groove 782 is closed by the head 852 of the second separator insertion hole 820. Furthermore, the end surface of the head 852, which is the insertion end of the separator 850, is exposed to the second annular space connecting groove 792 and the third connecting hole 840. Therefore, when the leak detection sensor 860 is inserted into the central hole of the separator 850, the probe portion of the leak detection sensor 860 can detect leaked fuel in the second annular space connecting groove 792 and the second connecting hole 840, and thus can detect fuel leaked into the annular space 3154a on one side of the double-walled bend 3100 and the connecting flange 900 (while also referring to...). Figures 27 to 28 ).

[0436] Thus, based on the liquid fuel supply pipeline and liquid fuel supply system equipped with the jumper-type common rail 60b, the connecting flange of the jumper 3000 can be easily configured as a leak detection block 750 capable of leak detection. Furthermore, at any time during the test steps before or during operation, leaks can be easily detected simply by inserting the separator 850 into the first separator insertion hole 810 and the second separator insertion hole 820 of the leak detection block 750, without the need for a separate, complex process.

[0437] Furthermore, since the common rail 60b of this disclosure is made in the form of connecting multiple high-pressure blocks 1000 and multiple jump pipes 3000, and a leak detection block 750 is provided in each jump pipe 3000, leaks can be detected at several points on the common rail, and the leak point can be located accurately and easily.

[0438] Furthermore, since the common rail 60b of this disclosure is made in the form of a jumper 3000 with a double-layer bend 3100 connecting the high-pressure blocks 1000 and the high-pressure blocks 1000, the double-layer bend 3100 is lightweight, thereby reducing the overall weight of the common rail. Therefore, it is very suitable for engines where leak detection is easy and weight reduction is required.

[0439] Furthermore, since the common rail 60b of this disclosure is made in the form of connecting multiple high-voltage blocks 1000 and multiple jumpers 3000, it can be repaired or replaced by disassembling each high-voltage block 1000 as a unit or each jumper 3000 as a unit, thus maintenance is easy and operating costs can be reduced.

[0440] [Leak detection devices and systems for liquid fuel supply pipelines]

[0441] Figures 57 to 59 This is a view used to illustrate a leak detection system for a high-pressure liquid fuel supply line according to this disclosure.

[0442] exist Figure 57 The diagram shows a view illustrating a leak detection system for a high-pressure liquid fuel supply line, wherein a leak detection connection 700 is applied to a high-pressure liquid fuel inlet line 50 according to the present disclosure, and a leak detection jumper 2000 is applied to a block common rail 60a.

[0443] (Leak detection device)

[0444] According to a specific embodiment of the leak detection device of this disclosure, it is implemented as being installed above through Figures 21 to 28 The leak detection block 750 is described in the high-pressure liquid fuel inlet line 50, outlet line 70 and jumper 3000.

[0445] According to another specific embodiment of the leak detection device of this disclosure, it is implemented to have the ability to detect leaks by means of... Figures 29 to 51 The jumper block 2000 of the partition attachment / removal part 2004 is described.

[0446] Leak detection devices implemented in the form of leak detection block 750 or jump block 2000 have the following four common and basic technical features.

[0447] First, a "main fuel line connection hole" that runs through the main body and an "annular space" formed around the main fuel line connection hole are provided.

[0448] Second, the annular space is divided into an "upstream annular space" and a "downstream annular space".

[0449] Third, a "separator insertion hole" is provided for connecting the upstream and downstream annular spaces.

[0450] Fourth, the connection structure of the upstream annular space, the downstream annular space, and the separator insertion hole is configured such that when the separator 850 is inserted into the separator insertion hole, the communication connection between the upstream annular space and the downstream annular space is closed by the head 852 of the separator 850, and the sensor insertion hole 854 leading to the end surface of the head 852 is connected to either the upstream annular space or the downstream annular space. (Therefore, when the leak detection sensor 860 is inserted into the sensor insertion hole 854, the probe of the leak detection sensor 860 is exposed at the end surface of the head, thereby enabling the detection of leakage in the corresponding annular space at the probe exposure point.) Figure 28 and Figure 51 Leak detection sensor 860 in the middle).

[0451] In passing Figures 21 to 28 In the leak detection block 750, the "main fuel line connection hole" is implemented as "main fuel line connection hole 762a". The "upstream annular space" is implemented as "first annular space connection groove 782". The "downstream annular space" is implemented as "second annular space connection groove 792". The "separator insertion hole" is implemented as "first separator insertion hole 810" or "second separator insertion hole 820".

[0452] In passing Figures 29 to 51 In the explained jump block 2000, "main fuel line connection hole" is implemented as "main fuel line connection hole 1100-1" (see...). Figure 32The "upstream annular space" is implemented as "upstream upper annular space connection groove 2232a and upstream lower annular space connection groove 2234b". The "downstream annular space" is implemented as "downstream upper annular space connection groove 2232b and downstream lower annular space connection groove 2234b". The "separator insertion hole" is implemented as "separator insertion hole 2500".

[0453] (Leak detection system for liquid fuel supply lines)

[0454] As described above, the liquid fuel supply line according to this disclosure includes: a high-pressure liquid fuel inlet line 50 with a double-walled structure; a common rail 60 with a double-walled structure connected to the downstream end of the high-pressure liquid fuel inlet line 50; and a discharge line 70 with a double-walled structure connected to the downstream end of the common rail 60.

[0455] The common and fundamental technical feature of this leak detection system for liquid fuel supply lines is that the leak detection device is installed in at least one of the high-pressure liquid fuel inlet line 50, common rail 60, or outlet line 70, so that leaks can be detected at the point where the corresponding leak detection device is installed.

[0456] Specific embodiments of the leak detection system disclosed herein can be implemented in the following three forms. That is, as a common rail 60, it can be divided into a block-type common rail 60a, a jump-pipe type common rail 60b, or a straight-pipe type common rail 60c.

[0457] (A leak detection system for liquid fuel supply lines using block-type common rail 60a)

[0458] Reference Figure 57 The liquid fuel supply system is equipped with the aforementioned high-pressure liquid fuel inlet pipe 50, block common rail 60a, and discharge pipe 70.

[0459] As described above, the high-pressure liquid fuel inlet line 50 has a main fuel line 52a and an annular space 54a. A block common rail 60a is connected to the downstream end of the high-pressure liquid fuel inlet line 50.

[0460] The high-pressure liquid fuel inlet pipeline 50 is divided into an upstream first inlet pipeline 50a and a downstream second inlet pipeline 50b, and these separate parts are connected by a leak detection connector 700. A leak detection separator 850 can be attached to or detached from the leak detection connector 700. The leak detection connector 700 is provided with a leak detection block 750, and the leak detection separator 850 can be attached to or detached from the leak detection block 750.

[0461] The block common rail 60a is provided with multiple high-pressure blocks 1000 (1000-1, 1000-2, ..., 1000-n) corresponding to each engine cylinder. Furthermore, jump blocks 2000 (2000-1, 2000-2, ..., 2000-n) are provided connecting adjacent high-pressure blocks 1000. The aforementioned main fuel line connection hole 2100 and annular space connection groove 1100-2 are formed along the entire length of the multiple high-pressure blocks 1000 and multiple jump blocks 2000.

[0462] In the middle of each jump block 2000 (2000-1, 2000-2, ..., 2000-n), a separator attachment / removal part 2004 (2004-1, 2004-2, ..., 2004-n) is provided, to which the separator 850 can be attached / removed. That is, a separator insertion hole 2500 (2500-1, 2500-2, ..., 2500-n) is provided in the separator attachment / removal part 2004 (2004-1, 2004-2, ..., 2004-n).

[0463] The discharge line 70 has a main fuel line 52a and an annular space 54a, and is connected to the downstream end of the block common rail 60a.

[0464] The discharge pipe 70 is divided into a first discharge pipe 70a on the upstream side and a second discharge pipe 70b on the downstream side, and the separated parts are connected by a leak detection connector 700. A leak detection separator 850 can be attached to or detached from the leak detection connector 700. The leak detection connector 700 is provided with a leak detection block 750, and the leak detection separator 850 can be attached to or detached from the leak detection block 750.

[0465] As described above, a leak alarm tank (not shown) is installed at the downstream end of the discharge line 70. It is used to recover liquid fuel leaked into the annular space of the high-pressure liquid fuel inlet line 50, the annular space of the block common rail 60a and the annular space of the discharge line 70 and to issue an alarm.

[0466] Leak detection can be performed during the final leak test of the manufactured engine. Additionally, leak detection can be performed while the engine is in use if a leak exceeding a reference amount of fuel is detected in the leak alarm reservoir and a leak alarm is triggered. In this case, leak detection is performed after the engine has been stopped and any remaining liquid fuel in the liquid fuel supply lines has been drained.

[0467] During leak detection, nitrogen (or another inert gas) is injected instead of liquid fuel into the inlet of the main fuel line 52a of the high-pressure liquid fuel inlet line 50, which is the upstream of the liquid fuel supply line.

[0468] If a leak occurs from the main fuel line due to a defect in any of the connections or other parts of the liquid fuel supply line, the leaked inert gas will flow into the annular space.

[0469] Leak detection is performed by detecting the oxygen concentration from the leak detection sensor 860, determining whether the oxygen concentration has fallen below a reference value due to a leak of inert gas (nitrogen, etc.), and if the oxygen concentration is below the reference value, determining that a leak has occurred in the annular space region connected to the corresponding partition 850.

[0470] For example, the separator 850 is inserted into the first separator insertion hole 810 and the second separator insertion hole 820 in the leak detection connection 700 formed in the high-pressure liquid fuel inlet pipe 50. Then, by inserting the separator 850 into the first separator insertion hole 810, it is possible to detect whether leaked nitrogen gas has been introduced into the annular space of a section on one side of the first inlet pipe 50a, which is the upstream side of the separator 850. Furthermore, by inserting the separator 850 into the second separator insertion hole 820, it is possible to detect whether leaked nitrogen gas has been introduced into the annular space of a section on one side of the second inlet pipe 50b, which is its downstream side.

[0471] Leak detection in the connection 700 of the discharge line 70 is performed in the same way as leak detection in the high-pressure liquid fuel inlet line 50.

[0472] Simultaneously, the separator 850 is sequentially inserted into the separator insertion holes 2500-1, 2500-2, ..., 2500-n formed in each of the block blocks 2000-1, 2000-2, ..., 2000-n of the block common rail 60a. Then, it is possible to detect whether a leak has occurred in the upstream section of the inserted separator 850.

[0473] For example, by inserting a leak detection separator 850 into the separator insertion hole 2500-2 of the second jump block 2000-2 of the block common rail 60a, it is possible to detect whether leaking gas has been introduced into the annular space between the first separator insertion hole 2500-1 and the second separator insertion hole 2500-2, which is the upstream side of the corresponding separator 850. In other words, it is possible to detect whether a leak has occurred in the section between the first separator insertion hole 2500-1 and the second separator insertion hole 2500-2.

[0474] Therefore, liquid fuel supply pipelines can be roughly divided into several zones, for example, such as Figure 57 As shown, the first section on one side of the high-pressure liquid fuel inlet pipeline 50, the second section on one side of the block common rail 60a, and the third section on one side of the outlet pipeline 70 can be inspected sequentially. Subsequently, by further subdividing the detected leaking section into specific segments and inspecting them sequentially, the specific segment or location of the leak can be narrowed down.

[0475] If a leak is detected by the leak detection sensor 860 in the first separator insertion hole 810 of the leak detection block 750 inserted into the high-pressure liquid fuel inlet line 50, it can be determined that a leak has occurred in the upstream section (first section) of the first inlet line 50a.

[0476] Furthermore, if the leak detection sensor 860 in the first separator insertion hole 810 of the leak detection connection 700 from the insertion to the discharge pipe 70 detects a leak, it can be determined that a leak has occurred in the section (second section) between the separator insertion hole 2500-n (2500-5) of the last jumper block 2000-n (referred to as "2000-5" in the figure) and the first discharge pipe 70a, and its upstream section (first section). In this case, if no leak occurs in the first section, it can be determined that a leak has occurred in the second section.

[0477] If a leak is detected by the leak detection sensor 860 in the second separator insertion hole 820 of the leak detection connector 700 inserted into the discharge pipe 70, it can be determined that a leak has occurred in a section (third section) of the second discharge pipe 70b, which is the downstream side of the corresponding leak detection connector 700.

[0478] Furthermore, if a leak is detected by the leak detection sensor 860 in the second separator insertion hole 820 of the leak detection block 750 inserted into the high-pressure liquid fuel inlet line 50, or if a leak is detected by the leak detection sensor 860 in the separator insertion hole 2500-1 of the first jump block 2000-1 inserted into the block common rail 60a, it can be determined that a leak has occurred in the section between the first separator insertion hole 810 of the leak detection block 750 of the high-pressure liquid fuel inlet line 50 and the separator insertion hole 2500-1 of the first jump block 2000-1.

[0479] This can narrow down the potential leakage points.

[0480] Here is an example of the process for finding the leak points in each section.

[0481] like Figure 57As shown, the liquid fuel supply pipeline can be divided into: a first section, including a first inlet pipeline 50a upstream of the high-pressure liquid fuel inlet pipeline 50 up to the leak detection block 750; a second section, including a block common rail 60a from the leak detection block 750 of the high-pressure liquid fuel inlet pipeline 50 to the leak detection block 750 of the outlet pipeline 70; and a third section, including a second outlet pipeline 70b downstream of the leak detection block 750 of the outlet pipeline 70.

[0482] Furthermore, the separator 850 is inserted into each of the first and second separator insertion holes 810 of the leak detection block 750 of the high-pressure liquid fuel inlet line 50. Subsequently, a leak in the first section is detected by inserting a leak detection sensor 860 into the separator 850 inserted in the first separator insertion hole 810.

[0483] If no leak is detected in the first section, leaks are detected in the second and third sections by inserting the separator 850 into each of the first and second separator insertion holes 810 of the leak detection block 750 in the discharge line 70. If a leak is detected from the separator 850 inserted into the first separator insertion hole 810, it is determined that a leak has occurred in the second section (since no leak occurred in the first section previously, it can be determined that the leak occurred in the second section). If a leak is detected from the separator 850 inserted into the second separator insertion hole 820, it is determined that a leak has occurred in the third section.

[0484] In the above process, if leaks in the first and third sections are not confirmed, but leaks in the second section are confirmed, detection is performed by sequentially inserting separators 850 and leak detection sensors 860 from upstream to downstream, starting from the separator insertion hole 2500-1 of the upstream jump block 2000-1 to the separator insertion hole 2500-n of the downstream jump block 2000-n. Then, it can be determined whether leaks have occurred in each section between adjacent jump blocks 2000.

[0485] As another method, detection can also be performed on each specific section by inserting the separator 850 into the first separator insertion hole 810 and the second separator insertion hole 820 in the leak detection connection 700 formed in the high-pressure liquid fuel inlet pipe 50, the first separator insertion hole 810 and the second separator insertion hole 820 formed in the leak detection connection 700 formed in the outlet pipe 70, and the separator insertion holes 2500 (2500-1 to 2500-5) of each jump block 2000 of the block common rail 60a.

[0486] Meanwhile, in liquid fuel supply lines, detection can be performed by inserting the separator 850 into the separator insertion hole of the point to be detected, and inserting a separately manufactured virtual separator into the remaining separator insertion holes.

[0487] Accordingly, leaks can be detected independently in the following sections: the section of the first inlet pipe 50a upstream of the leak detection connection 700 of the high-pressure liquid fuel inlet pipe 50, the section between the second inlet pipe 50b downstream of the leak detection connection 700 of the high-pressure liquid fuel inlet pipe 50 and the separator insertion hole 2500-1 of the first jump block 2000-1, the section between the two separator insertion holes 2500 of adjacent jump blocks 2000, the section between the separator insertion hole 2500-5 of the last jump block 2000-5 and the first discharge pipe 70a upstream of the leak detection connection 700 of the discharge pipe 70, and the section of the second discharge pipe 70b downstream of the leak detection connection 700 of the discharge pipe 70.

[0488] (A leak detection system for liquid fuel supply lines using the jump-pipe common rail 60b)

[0489] Next, in Figure 58 The image shows a view used to illustrate leak detection in a high-pressure liquid fuel supply line including a jump-pipe common rail 60b.

[0490] Leak detection connector 700 is applied to high-pressure liquid fuel inlet line 50, leak detection block 750 is applied to common rail 60b with jump pipe, and leak detection connector 700 is applied to leak detection connector 700.

[0491] Reference Figure 58 The liquid fuel supply line is constructed by including a high-pressure liquid fuel inlet line 50, a jump-pipe common rail 60b, and an outlet line 70.

[0492] The high-pressure liquid fuel inlet pipeline 50 is provided with a leak detection connection 700 and a leak detection block 750, and a leak detection separator 850 can be attached to or removed from it.

[0493] The jump-pipe common rail 60b is equipped with a leak detection block 750 (750-1, 750-2, ..., 750-n), and a leak detection separator 850 can be attached to or removed from it.

[0494] In addition, the discharge pipe 70 is provided with a leak detection connection 700 and a leak detection block 750, and a leak detection separator 850 can be attached to or removed from it.

[0495] At the downstream end of the discharge line 70, a leak alarm tank (not shown) is installed to recover liquid fuel leaked into the annular space of the high-pressure liquid fuel inlet line 50, the annular space of the jump-pipe common rail 60b, and the annular space of the discharge line 70 and to issue an alarm.

[0496] In this leak detection system, the method for detecting leaks is the same as described above. Figure 57 The leak detection method described herein is the same.

[0497] To illustrate one example, when the separator 850 and the leak detection sensor 860 are sequentially inserted from upstream to downstream based on the direction of liquid fuel flow into the first and second separator insertion holes 810 and 820 formed in the leak detection block 750 of the high-pressure liquid fuel inlet pipe 50; the first and second separator insertion holes 810 and 820 formed in the leak detection blocks 750-1, 750-2, ..., 750-n of the multiple jump pipes 3000-1, 3000-2...3000-n of the jump pipe common rail 60b; and the first and second separator insertion holes 810 and 820 formed on the leak detection block 750 of the discharge pipe 70, a leak in the liquid fuel flow can be detected.

[0498] Furthermore, the liquid fuel supply pipeline can be divided into: a first section, including a first inlet pipeline 50a extending upstream of the high-pressure liquid fuel inlet pipeline 50 to the leak detection block 750; a second section, including a common rail 60a of the leak detection block 750 from the high-pressure liquid fuel inlet pipeline 50 to the outlet pipeline 70; and a third section, including a second outlet pipeline 70b downstream of the leak detection block 750 of the outlet pipeline 70, and detection is performed for each section.

[0499] That is, the separator 850 is inserted into each of the first and second separator insertion holes 810 of the leak detection block 750 of the high-pressure liquid fuel inlet line 50, and the leak in the first section is detected by inserting the leak detection sensor 860 into the separator 850 inserted in the first separator insertion hole 810.

[0500] Subsequently, the separator 850 is inserted into each of the first and second separator insertion holes 810 of the leak detection block 750 of the discharge pipe 70. The leak in the second section is detected by inserting the leak detection sensor 860 into the separator 850 inserted in the first separator insertion hole 810, and the leak in the third section is detected by inserting the leak detection sensor 860 into the separator 850 inserted in the second separator insertion hole 820.

[0501] If leaks in the first and third sections are not confirmed, but leaks in the second section are confirmed, then the presence of leaks in each section between adjacent bridging blocks 2000 is determined by sequentially inserting separators 850 and leak detection sensors 860 from upstream to downstream, starting from the separator insertion hole 2500-1 of the upstream bridging block 2000-1 of the block common rail 60a to the separator insertion hole 2500-n of the downstream jumper block 2000-n.

[0502] (Leak detection system for liquid fuel supply pipeline using straight common rail 60c)

[0503] Next, in Figure 59 The image shows a view illustrating a leak detection system for a high-pressure liquid fuel supply line including a straight common rail 60c according to the present disclosure.

[0504] Reference Figure 59 In the high-pressure liquid fuel inlet pipeline 50, a leak detection connection 700 is provided, and a leak detection separator 850 can be attached to or removed from it.

[0505] The straight-pipe common rail 60c is configured with: a straight pipe 4000 with a high-pressure double-layer pipe structure extending along the cylinder arrangement direction; branch pipes 4100 (4100-1, 4100-2, ..., 4100-n) with a high-pressure double-layer pipe structure branching from the straight pipe 4000 toward each cylinder; and leakage detection blocks 750 (750-1, 750-2, ..., 750-n) installed in the middle of each branch pipe 4100 (4100-1, 4100-2, ..., 4100-n).

[0506] In addition, a leak detection connection 700 is provided in the discharge pipe 70, and a leak detection separator 850 can be attached to or removed from it.

[0507] At the downstream end of the discharge line 70, a leak alarm tank (not shown) is installed to recover liquid fuel that has leaked into the annular space of the high-pressure liquid fuel inlet line 50, the annular space of the straight common rail 60c, and the annular space of the discharge line 70 and to issue an alarm.

[0508] This straight-pipe common rail 60c provides a structure in which branch pipes 4100 (4100-1, 4100-2, ..., 4100-n) branch in the middle of each of the straight pipes 4000 in a simple double-layer pipe structure, and the middle of each branch pipe can be simply connected to the leak detection block 750 (750-1, 750-2, ..., 750-n).

[0509] Furthermore, since the common rail leak detection zone can be easily subdivided and set into sections between adjacent branches, leaks can be detected at several points on the common rail, and the leak location can be found accurately and easily.

[0510] Furthermore, since the straight-pipe common rail 60c of this disclosure is entirely constructed from a double-layered straight pipe 4000 and a branch pipe 4100, the overall weight of the common rail can be reduced. Therefore, it is highly suitable for engines where leak detection is easy and weight reduction is required.

[0511] The leak detection method in a leak detection system equipped with a liquid fuel supply pipeline of this straight common rail 60c is the same as the above. Figure 57 and Figure 58 The leak detection method described herein is the same.

[0512] In other words, inert gas is injected into the main fuel line 52a of the high-pressure liquid fuel inlet line 50.

[0513] Subsequently, while inserting the separator 850 and the leak detection sensor 860 sequentially into the first and second separator insertion holes 810 and 820 formed in the leak detection block 750 of the high-pressure liquid fuel inlet pipe 50, the first and second separator insertion holes 810 and 820 formed in each of the multiple branch pipes 4100-1, 4100-2, ..., 4100-n, and the first and second separator insertion holes 810 and 820 formed in the leak detection block 750 of the discharge pipe 70 from upstream to downstream based on the liquid fuel flow direction, a liquid fuel leak can be detected.

[0514] Furthermore, for example, the liquid fuel supply line may be divided into: a first section, including a first inlet line 50a upstream of the high-pressure liquid fuel inlet line 50 up to the leak detection block 750; a second section, including a straight common rail 60c from the leak detection block 750 of the high-pressure liquid fuel inlet line 50 to the leak detection block 750 of the outlet line 70; and a third section, including a second outlet line 70b downstream of the leak detection block 750 of the outlet line 70, and for which detection is performed.

[0515] That is, the separator 850 is inserted into each of the first and second separator insertion holes 810 of the leak detection block 750 of the high-pressure liquid fuel inlet line 50, and the leak in the first section is detected by inserting the leak detection sensor 860 into the separator 850 inserted in the first separator insertion hole 810.

[0516] Subsequently, a leak in the second section is detected by inserting the separator 850 into each of the first and second separator insertion holes 810 of the leak detection block 750 in the discharge pipe 70, by inserting the leak detection sensor 860 into the separator 850 inserted in the first separator insertion hole 810, and a leak in the third section is detected by inserting the leak detection sensor 860 into the separator 850 inserted in the second separator insertion hole 820.

[0517] If a leak in the first and third sections is not confirmed but a leak in the second section is confirmed, then the separator 850 is inserted into the first and second separator insertion holes 810 and 820 of the leak detection block 750 provided in each branch pipe 4100-1, 4100-2, ..., 4100-n of the straight common rail 60c, and the leak in the downstream section (engine side section) of the leak detection block 750 of each branch pipe 4100-1, 4100-2, ..., 4100-n is detected by inserting the leak detection sensor 860 into the separator 850 inserted in the second separator insertion hole 820.

[0518] If no leakage is detected in the downstream section (engine side section) of the leakage detection block 750 of each branch pipe 4100-1, 4100-2, ..., 4100-n, then the leakage of the section of the straight pipe 4000 is detected by inserting a separator 850 into the first separator insertion hole 810 of any one or more of the leakage detection blocks 750 of each branch pipe 4100-1, 4100-2, ..., 4100-n, and inserting a leakage detection sensor 860 into the separator 850 inserted in the first separator insertion hole 810.

[0519] Specific preferred embodiments of this disclosure have been shown and explained above. However, this disclosure is not limited to the above embodiments, and any person skilled in the art to which this invention pertains can perform various modified implementations without departing from the subject matter of this disclosure as claimed in the claims.

Claims

1. A liquid fuel supply system, comprising: Engine structure (6) is located inside the engine compartment; A liquid fuel tank (30) is configured to store liquid fuel in an area isolated from the cabin; A low-pressure liquid fuel pump (31) is configured to supply liquid fuel from the liquid fuel tank (30) to the engine; A low-pressure delivery pipe (32) is configured to deliver low-pressure liquid fuel from the low-pressure liquid fuel pump (31) to the engine structure (6) in the engine room. A liquid fuel pressurization unit (100) is configured to pressurize the low-pressure liquid fuel received from the low-pressure delivery pipe (32) to a high pressure and discharge it therefrom; The high-pressure liquid fuel inlet line (50), made of high-pressure double-layer pipe, is used to deliver high-pressure liquid fuel discharged from the liquid fuel pressurization unit (100) toward the cylinder; Common rail (60), configured to distribute the high-pressure liquid fuel supplied from the high-pressure liquid fuel inlet line (50) to each cylinder; and The discharge pipe (70), made of double-layered pipe, is connected to the outlet of the common rail (60).

2. The liquid fuel supply system according to claim 1, comprising: A low-pressure hydraulic pump (23) is configured to supply low-pressure operating oil to the liquid fuel pressurization unit (100); as well as The motor (22) is configured to drive the low-pressure hydraulic pump (23). The liquid fuel pressurization unit (100) pressurizes the low-pressure liquid fuel into high-pressure liquid fuel under the pressure of the low-pressure operating oil supplied from the low-pressure hydraulic pump (23).

3. The liquid fuel supply system according to claim 2, wherein the liquid fuel pressurization unit (100) is configured as a piston-operated pressurization unit, the piston-operated pressurization unit being configured to operate the piston by receiving pressure from low-pressure operating oil supplied from the low-pressure hydraulic pump (23) to perform pressurization to high pressure.

4. The liquid fuel supply system according to claim 1, wherein the liquid fuel pressurization unit (100) comprises: The piston pump unit (500) is configured to pressurize low-pressure liquid fuel to high pressure and discharge it under the pressure of operating oil; as well as The operating oil control unit (200) is configured to control the supply and discharge of low-pressure operating oil to the piston pump unit (500).

5. The liquid fuel supply system according to claim 4, wherein the piston pump unit (500) comprises a plurality of plunger pump sections (P500) arranged in parallel, and The operating oil control unit (200) includes a plurality of valve sections (V300) configured to supply and discharge low-pressure operating oil to the plurality of plunger pump sections (P500), and The plurality of valve sections (V300) are configured to operate sequentially at equal intervals, such that the plurality of plunger pump sections (P500) pressurize and discharge liquid fuel sequentially at equal intervals.

6. The liquid fuel supply system according to claim 5, wherein the operating oil control unit (200) comprises: A rotary valve shaft (300) is configured to control the flow direction of operating oil within a control cylinder (212); as well as Multiple operating oil supply ports (214) are respectively connected to the multiple plunger pump sections (P500) from the control cylinder (212), and The plurality of valve portions (V300) are formed on the outer periphery of the valve shaft (300) to maintain an axial spacing corresponding to the positions of the plurality of operating oil supply ports (214) while maintaining an equal phase difference in the rotational direction.

7. The liquid fuel supply system according to claim 6, wherein each valve section (V300) of the valve shaft (300) includes an inlet groove (304) and an outlet groove (306), the inlet groove being configured to supply the operating oil to the plunger pump section (P500) when it encounters and communicates with the operating oil supply port (214), and the outlet groove being configured to discharge the operating oil from the plunger pump section (P500) when it encounters and communicates with the operating oil supply port (214).

8. The liquid fuel supply system according to claim 7, wherein in each valve portion (V300) of the valve shaft (300), a total of two inlet grooves (304) are formed in a symmetrical shape on the left and right sides of the cross section of the valve shaft (300), and a total of two outlet grooves (306) are formed in a symmetrical shape on the left and right sides in a direction orthogonal to the inlet grooves (304), such that the valve shaft (300) performs two operating oil supply / discharge operations and two liquid fuel pressurization operations for each rotation.

9. The liquid fuel supply system according to claim 5, wherein each of the plurality of plunger pump sections (P500) of the liquid fuel pressurization unit (100) comprises: The low-pressure section cylinder (502) forms a low-pressure chamber (C1) filled with operating oil through the operating oil supply port (214) and has a large diameter; The high-pressure cylinder (504) forms a high-pressure chamber (C2) filled with low-pressure liquid fuel on the opposite side of the low-pressure chamber (C1), and has a diameter smaller than that of the low-pressure cylinder (502). A pressurizing plunger (600), wherein a low-pressure piston (610) is formed on one side and installed in the low-pressure cylinder (502), and a high-pressure piston (620) is formed on the opposite side and installed in the high-pressure cylinder (504); and The high-pressure liquid fuel discharge flow path (514) is configured to deliver the high-pressure liquid fuel, which has been pressurized and increased in pressure by the high-pressure piston (620), toward the cylinder.

10. The liquid fuel supply system according to claim 1, wherein the high-pressure liquid fuel inlet pipe (50) is made of a high-pressure double-walled pipe having an inner pipe (52) forming a main fuel pipe (52a) inside and an outer pipe (54) maintaining an annular space (54a) outside the inner pipe (52), and The high-pressure liquid fuel inlet pipe (50) is divided into a first inlet pipe (50a) located upstream of the liquid fuel flow direction and a second inlet pipe (50b) located downstream of the liquid fuel flow direction. The separated first inlet pipe (50a) and second inlet pipe (50b) are connected to each other by a leak detection connector (700). A leak detection separator (850) can be attached to the leak detection connector / can be detached from the leak detection connector.

11. The liquid fuel supply system according to claim 10, wherein the leak detection connection (700) comprises: The connecting flange (710) of the double-layer pipe structure is connected to the first inlet pipe (50a); as well as The leak detection block (750), connected to the second inlet pipe (50b), is fastened to abut the connecting flange (710) and is configured to allow the leak detection separator (850) to be attached / removed.

12. The liquid fuel supply system of claim 10, wherein the leak detection block (750) comprises: The first annular space connecting groove (782) and the second annular space connecting groove (792) are connected to the annular space of the connecting flange (710) and the second annular space connecting groove is connected to the annular space (54a) of the second inlet pipe (50b). The first separator insertion hole (810) is connected to one end of the width direction of the first annular space connecting groove (782) and the second annular space connecting groove (792); The second separator insertion hole (820) is connected to the other end of the width direction of the first annular space connecting groove (782) and the second annular space connecting groove (792); The first connecting hole (830) connects one end of the first separator insertion hole (810) and the middle part of the second separator insertion hole (820); as well as The second connecting hole (840) connects across the first separator insertion hole (810) and one end of the plug (802), and Wherein, by inserting the leak detection separator (850) into each of the first separator insertion hole (810) and the second separator insertion hole (820), the communication connection between the two ends of the second annular space connection groove (792) and the first annular space connection groove (782) is closed, and one end of each separator (850) is exposed to the interior of the first communication hole (830) communicating only with the first annular space connection groove (782) and the interior of the second communication hole (840) communicating only with the second annular space connection groove (792).

13. The liquid fuel supply system of claim 1, wherein the common rail (60) is configured as a block common rail (60a), the block common rail (60a) comprising: Multiple high-pressure blocks (1000) are arranged in parallel with the engine cylinders and installed on the engine block; Jump block (2000) has a solid block-shaped body and is connected between adjacent high-voltage blocks (1000); The main fuel line connection hole (1100-1) is penetrated to form a through-hole connecting the high-pressure block (1000) and the jumper block (2000) at their cross-sectional center, while branching through towards the engine block; and The annular space connection groove (1100-2) is penetrated to form a through connection between the high-pressure block (1000) and the jump block (2000), while being connected in parallel with the main fuel line connection hole (1100-1) and maintaining a horizontal position relative to the ground without any height difference.

14. The liquid fuel supply system according to claim 13, wherein the annular space connection groove (1100-2) is configured with an upper annular space connection groove (1100-2a) and a lower annular space connection groove (1100-2b) respectively penetrating the upper and lower parts of the main fuel pipeline connection hole (1100-1) to penetrate and connect the high pressure block (1000) and the jumper block (2000) in parallel with the main fuel pipeline connection hole (1100-1) and remain horizontal with no height difference relative to the ground.

15. The liquid fuel supply system according to claim 13, wherein the jump block (2000) includes a separator attachment / removal portion (2004) at the midpoint of the block-shaped body portion (2001) in the longitudinal direction, and The leak detection separator (850) used to detect whether leakage occurs inside the upper annular space connecting groove (1100-2a) and the lower annular space connecting groove (1100-2b) can be attached to the separator attachment / removal part (2004) or removed from the separator attachment / removal part.

16. The liquid fuel supply system of claim 1, wherein the common rail (60) is configured as a jump-pipe common rail (60b), the jump-pipe common rail (60b) comprising: Multiple high-pressure blocks (1000) are arranged in parallel with the engine cylinders and installed on the engine block; as well as A jumper tube (3000) is connected between adjacent high-voltage blocks (1000); and The jumper tube (3000) mentioned above includes: A double-walled bend (3100) having an inner tube (3152) forming a main fuel line (3152a) at its center and an outer tube (3154) maintaining an annular space (3154a) outside the inner tube (3152); and A leak detection block (750) is disposed at the upstream end of the double-walled bend (3100), connected to abut the downstream flange (1003) of the high-pressure block (1000), and configured to allow the partition (850) for detecting liquid fuel leaks in the annular space (3154a) to be attached / removed.

17. A vessel comprising a liquid fuel supply system according to any one of claims 1, 2, 4, 10, 13 or 16.

Images