High-pressure common-rail oil inlet proportional valve of heavy oil diesel engine

Abstract

The utility model relates to a heavy oil diesel engine high pressure common rail oil inlet proportional valve which comprises a proportional valve body with the right end connected with an electromagnetic valve in a matched mode and a sliding valve sleeve arranged in an inner cavity of the proportional valve body in a matched mode, and a sliding valve element, a spring seat, a spiral spring and a screw plug are sequentially arranged in the sliding valve sleeve from right to left. The proportional valve body is provided with a lubricating oil inlet channel, a lubricating oil return channel, a first mixed oil return channel and a second mixed oil return channel which are communicated with an inner cavity of the proportional valve body; the left part in the slide valve sleeve is a spring operation section, the right part is a matching part matching section, and a step is formed at the joint of the two sections; a first mixed oil return hole and a second mixed oil return hole are formed in the matching part matching section, and a large groove is formed in the right end of the sliding valve sleeve; the sliding valve element is dumbbell-shaped and matched with the matching part matching section of the sliding valve sleeve, a through hole is formed in the center of the sliding valve element, and a U-shaped groove is formed in the right end of the sliding valve element. The left end of the valve element and an adjacent component form a left oil chamber, and the right end of the valve element and an adjacent component form a right oil chamber. The problem that sliding valve matching parts of a proportional valve of a marine diesel engine are blocked when heavy oil is used can be solved.

Description

Technical Field

[0001] This utility model relates to marine diesel engines, specifically to a high-pressure common rail fuel injection proportional valve for heavy oil diesel engines. It enables automatic real-time control of the fuel supply from the high-pressure fuel pump in the high-pressure common rail fuel injection system of a marine heavy oil diesel engine, thereby achieving the function of pressure regulation of the common rail system. Background Technology

[0002] For high-pressure common rail fuel injection systems in marine diesel engines, the fuel proportioning valve is one of the key components for regulating the fuel pressure of the common rail system. It is installed at the fuel inlet of the high-pressure fuel pump, connecting the low-pressure fuel delivery pump and the high-pressure injection pump. By calculating the fuel demand of the common rail system, it provides the high-pressure fuel pump with a fuel supply that matches the demand, ensuring the stability of the common rail pressure from the source.

[0003] Heavy fuel oil is cheaper than light diesel oil, making it the primary fuel choice for diesel engines in ocean-going vessels. Currently, domestically produced diesel engines using heavy fuel oil are primarily mechanical, and there is virtually no experience with using heavy fuel oil in domestically produced high-pressure common rail diesel engines. From the perspective of the inlet proportional valve, during engine shutdowns, the oil temperature drops, and the heavy fuel oil in the gap between the solenoid proportional valve's spool valve assembly is not completely converted to light fuel, resulting in a mixture of light and heavy fuel oil. Under light fuel operating conditions, the temperature decreases, and the viscosity increases, easily causing the spool valve assembly to jam, leading to a loss of sensitivity in pressure regulation of the common rail system. Therefore, it is necessary to develop an inlet proportional valve suitable for heavy fuel oil diesel engines.

[0004] CN209586568U discloses a "Marine Low-Speed ​​Engine Electro-hydraulic Control Proportional Oil Inlet Valve," which includes a servo control valve assembly and a fuel control valve assembly. The servo control valve assembly includes a servo oil inlet, a servo oil return outlet, a pressure reducing valve assembly, a proportional solenoid, a proportional pressure reducing valve assembly, and a piston assembly. The servo control valve assembly regulates servo oil pressure; the servo oil can flow directly from the high-pressure oil source of the low-speed engine servo system, eliminating the need for an additional servo oil source. Fuel is introduced through the fuel control valve assembly; the fuel and servo oil have different oil passages to prevent mixing and contamination of the fuel. By employing electro-hydraulic servo control, direct contact between the electromagnetic components of the servo control valve and heavy oil is avoided, preventing corrosion. The servo control valve assembly controls the fuel control valve assembly, achieving proportional metering and output of fuel flow, while also regulating the common rail pressure. However, the technical solution disclosed in this patent document does not address how to solve the problem of valve assembly jamming. Utility Model Content

[0005] The utility model discloses a heavy oil diesel engine high pressure common rail oil inlet proportional valve, which can solve the problem of proportional valve spool component jam in the high pressure common rail fuel injection system of marine diesel engine under heavy oil use condition, and ensure the rail pressure stability of the high pressure common rail fuel injection system.

[0006] The utility model discloses a heavy oil diesel engine high pressure common rail oil inlet proportional valve, including the proportional valve body that right end cooperates with solenoid valve and the slide valve sleeve that cooperates in its inner chamber, be equipped with slide valve core, spring seat, helical spring and screw plug from right to left in the slide valve sleeve, proportional valve body is equipped with the lubricating oil inlet channel, lubricating oil back oil channel, first mixed back oil channel and second mixed back oil channel with its inner chamber intercommunication,

[0007] The left part in the slide valve sleeve is spring operation section, and the right part is component cooperation section, and the connecting place of two sections forms a step, and the first mixed back oil hole and the second mixed back oil hole are equipped on the component cooperation section, and the right end of the slide valve sleeve is equipped with a large recess,

[0008] The slide valve core is dumbbell type, and the diameters of the left end and the right end of the valve core are equal and cooperate with the component cooperation section of the slide valve sleeve, the center of the slide valve core is equipped with a through hole, and the right end is equipped with a U-shaped groove, and the left end of the valve core forms a left oil chamber with the adjacent component, and the right end of the valve core forms a right oil chamber with the adjacent component.

[0009] Further, the lubricating oil inlet channel is arranged at the right end of the proportional valve body and is connected with the lubricating oil pump, the lubricating oil back oil channel is arranged at the left end of the proportional valve body and is communicated with the lubricating oil tank, and the first mixed back oil channel and the second mixed back oil channel are arranged at the middle part of the proportional valve body and are respectively communicated with the first mixed back oil hole and the second mixed back oil hole on the component cooperation section of the slide valve sleeve.

[0010] Further, the left end of the slide valve sleeve is threadedly connected with the proportional valve body and extends out of the left end of the proportional valve body.

[0011] Further, the bottom of the spring seat is provided with a small recess, the spring seat is arranged at the connecting position of the spring operation section and the component cooperation section in the slide valve sleeve, the screw plug is connected with the left end in the slide valve sleeve, and the helical spring is arranged between the spring seat and the screw plug.

[0012] Further, the left end and the right end of the slide valve core are respectively provided with helical grooves, and the left end of the through hole of the slide valve core is a hexagonal hole.

[0013] Further, the screw plug is provided with a center hole, the right end of the center hole corresponds to the hexagonal hole, and the right end is sealed by a screw.

[0014] Further, the left end of the spool valve core abuts the bottom of the spring seat, and forms a left oil chamber with the adjacent spool valve sleeve and screw plug, and the right end of the spool valve core abuts the valve core of the electromagnetic valve, and forms a right oil chamber with the adjacent spool valve sleeve and electromagnetic valve.

[0015] The beneficial effects of the present scheme are:

[0016] Due to the design of lubricating the gap between the spool valve components by introducing lubricating oil, the proportioning valve has the characteristics of reducing the risk of spool valve component jamming;

[0017] Due to the design of the left end of the through hole of the spool valve core being a hexagonal hole and the design of the center hole of the screw plug, not only can the gap between the spool valve components be lubricated, but also the horizontal thrust on the spool valve core due to the fluctuation of the oil pressure can be eliminated, and the spool valve core can be rotated by a hexagonal wrench to determine whether the spool valve components are jammed.

[0018] Due to the design of the spool valve sleeve step, the integration design of the spring running section and the component fitting section of the spool valve sleeve, the initial position of the spool valve core can be limited when the spool valve components are disassembled and replaced, so that the performance characteristics of the proportioning valve are not affected;

[0019] Due to the dumbbell-shaped design of the spool valve core with large diameters at both ends and a small diameter in the middle, the horizontal thrust on the spool valve core due to the fluctuation of the oil pressure can be balanced, thereby improving the stability of the spool valve core, and the proportioning valve has the advantage of stable performance characteristics. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a structural schematic view of the present utility model;

[0021] Figure 2 It is a structural schematic view of the proportioning valve body;

[0022] Figure 3 It is a structural schematic view of the spool valve sleeve;

[0023] Figure 4 It is a structural schematic view of the spool valve core;

[0024] Figure 5 It is Figure 4 the left view;

[0025] Figure 6 It is a structural schematic view of the spring seat;

[0026] Figure 7 It is a structural schematic view of the screw plug.

[0027] In the figure (the technical features indicated by the marks):

[0028] 1 - proportional valve body, 11 - lubricating oil inlet channel, 12 - lubricating oil return channel, 13 - first mixed return channel, 14 - second mixed return channel;

[0029] 2 - spool sleeve, 21 - first mixed return hole, 22 - second mixed return hole, 23 - large groove;

[0030] 3 - spool core, 31 - left end of valve core, 32 - right end of valve core, 33 - through hole, 34 - hexagonal hole, 35 - U-shaped groove;

[0031] 4 - spring seat, 41 - small groove;

[0032] 5 - coil spring;

[0033] 6 - screw plug, 61 - center hole;

[0034] 7 - screw;

[0035] 8 - solenoid valve, 81 - valve core. DETAILED DESCRIPTION

[0036] The technical scheme of the utility model will be described in detail below with reference to the drawings.

[0037] Referring to Figures 1 to 7 A heavy oil diesel engine high-pressure common rail oil inlet proportional valve is shown in the figure, which comprises a proportional valve body 1 connected with a solenoid valve 8 at the right end and a spool sleeve 2 fitted in the inner cavity thereof, wherein a spool core 3, a spring seat 4, a coil spring 5 and a screw plug 6 are sequentially arranged in the spool sleeve 2 from right to left; the proportional valve body 1 is provided with a lubricating oil inlet channel 11, a lubricating oil return channel 12, a first mixed return channel 13 and a second mixed return channel 14 communicated with the inner cavity thereof;

[0038] The left part of the spool sleeve 2 is a spring running section, and the right part is a matching section of the coupling part, and the connecting part of the two sections forms a step; the matching section of the coupling part is provided with a first mixed return hole 21 and a second mixed return hole 22, and the right end of the spool sleeve 2 is provided with a large groove 23;

[0039] The spool core 3 is in the shape of dumbbell, the diameters of the left end 31 of the valve core and the right end 32 of the valve core are equal and matched with the matching section of the coupling part of the spool sleeve 2, the center of the spool core 3 is provided with a through hole 33, and the right end is provided with a U-shaped groove 35; the left end 31 of the valve core and the adjacent component form a left oil chamber, and the right end 32 of the valve core and the adjacent component form a right oil chamber.

[0040] The lubricating oil inlet channel 11 is arranged at the right end of the proportional valve body 1 and connected with the lubricating oil pump, and the lubricating oil return channel 12 is arranged at the left end of the proportional valve body 1 and communicated with the lubricating oil tank; the first mixed oil return channel 13 and the second mixed oil return channel 14 are arranged at the middle part of the proportional valve body 1 and respectively communicated with the first mixed oil return hole 21 and the second mixed oil return hole 22 on the matching segment of the slide valve sleeve 2.

[0041] The left end of the slide valve sleeve 2 is threadedly connected with the proportional valve body 1 and extends out of the left end of the proportional valve body 1.

[0042] The bottom of the spring seat 4 is provided with a small groove 41, the spring seat 4 is arranged on the step formed at the connecting position between the spring running segment and the matching segment of the slide valve sleeve 2, the plug 6 is connected with the left end of the slide valve sleeve 2, and the helical spring 5 is arranged between the spring seat 4 and the plug 6. The plug is connected with the left end of the slide valve sleeve through threads, and the spring seat is pressed on the step by the helical spring to position the initial position of the slide valve core.

[0043] The left end 31 and the right end 32 of the slide valve core 3 are respectively provided with helical grooves, and the left end of the through hole 33 of the slide valve core 3 is a hexagonal hole 34. Through the above structure, the lubrication of the matching gap of the slide valve matching part can be realized, the transverse thrust on the slide valve core due to the fluctuation of the lubricating oil pressure can be eliminated, and the slide valve core can be rotated by using an internal hexagonal wrench to determine whether the slide valve matching part is stuck.

[0044] The plug 6 is provided with a central hole 61, the right end of the central hole 61 corresponds to the hexagonal hole 34, and the right end is blocked by the screw 7.

[0045] The left end 31 of the slide valve core 3 abuts against the bottom of the spring seat 4 and forms a left oil chamber together with the adjacent slide valve sleeve 2 and plug 6, and the right end of the slide valve core 3 abuts against the core 81 of the electromagnetic valve 8 and forms a right oil chamber together with the adjacent slide valve sleeve 2 and electromagnetic valve 8. The oil chambers are formed at both ends of the slide valve core, which facilitates the sealing of lubricating oil and balances the transverse thrust on the valve core due to the fluctuation of the oil pressure.

[0046] The lubricating oil flows into the right oil chamber through the large groove 23U at the right end of the slide valve sleeve 2 from the lubricating oil inlet channel 11 of the proportional valve body 1; on one hand, the lubricating oil in the right oil chamber enters the matching gap of the slide valve matching part through the helical groove on the surface of the right end core 32 of the slide valve core 3 and flows out of the proportional valve into the mixed oil tank through the first mixed oil return hole 21 of the slide valve sleeve 2; on the other hand, the lubricating oil in the right oil chamber enters the left oil chamber through the through hole 33 of the slide valve core 3, and the lubricating oil in the left oil chamber enters the matching gap of the slide valve matching part through the small groove 41 at the bottom of the spring seat 4 and the helical groove on the surface of the left end core 31 of the slide valve core 3 and flows out of the proportional valve into the mixed oil tank through the second mixed oil return hole 22 of the slide valve sleeve 2.

Claims

1. A high-pressure common rail proportional valve for heavy oil diesel engines, comprising a proportional valve body (1) connected to a solenoid valve (8) at its right end and a spool sleeve (2) fitted within its inner cavity, wherein a spool core (3), a spring seat (4), a helical spring (5), and a plug (6) are arranged sequentially from right to left within the spool sleeve (2), characterized in that: The proportional valve body (1) is provided with lubricating oil inlet channel (11), lubricating oil return channel (12), first mixed oil return channel (13) and second mixed oil return channel (14) which communicate with the inner cavity of the proportional valve body (1); The left part of the spool sleeve (2) is spring running section, the right part is matching section of the pair of components, and the connecting part of the two sections forms a step; the matching section of the pair of components is provided with first mixed oil return hole (21) and second mixed oil return hole (22), and the right end of the spool sleeve (2) is provided with large groove (23); The spool core (3) is dumbbell type, the diameters of the left end (31) and the right end (32) of the spool core (3) are equal and match with the matching section of the pair of components of the spool sleeve (2), the center of the spool core (3) is provided with through hole (33), and the right end is provided with U-shaped groove (35); the left end (31) of the spool core (3) forms left oil chamber with the adjacent components, and the right end (32) of the spool core (3) forms right oil chamber with the adjacent components.

2. The heavy oil diesel engine high pressure common rail fuel inlet proportional valve according to claim 1, characterized in that: The lubricating oil inlet channel (11) is arranged at the right end of the proportional valve body (1) and connected with the lubricating oil pump, the lubricating oil return channel (12) is arranged at the left end of the proportional valve body (1) and communicates with the lubricating oil tank, and the first mixed oil return channel (13) and the second mixed oil return channel (14) are arranged at the middle part of the proportional valve body (1) and respectively correspond to the first mixed oil return hole (21) and the second mixed oil return hole (22) on the matching section of the pair of components of the spool sleeve (2).

3. The heavy oil diesel engine high pressure common rail fuel admission proportional valve according to claim 1 or 2, characterized by: The left end of the spool sleeve (2) is threadedly connected with the proportional valve body (1) and extends out of the left end of the proportional valve body (1).

4. The heavy oil diesel engine high pressure common rail fuel inlet proportional valve according to claim 3, characterized in that: The bottom of the spring seat (4) is provided with small groove (41), the spring seat (4) is arranged at the step formed by the connecting part of the spring running section and the matching section of the pair of components in the spool sleeve (2), the left end of the plug (6) is connected with the spool sleeve (2), and the helical spring (5) is arranged between the spring seat (4) and the plug (6).

5. The heavy oil diesel engine high pressure common rail fuel inlet proportional valve according to claim 4, characterized in that: The left end (31) and the right end (32) of the spool core (3) are respectively provided with helical grooves, and the left end of the through hole (33) of the spool core (3) is hexagonal hole (34).

6. The heavy oil diesel engine high pressure common rail fuel inlet proportional valve according to claim 5, characterized in that: The plug (6) is provided with center hole (61), the right end of the center hole (61) corresponds to the hexagonal hole (34), and the right end is sealed by screw (7).

7. The heavy oil diesel engine high pressure common rail fuel inlet proportional valve according to claim 1, characterized in that: The left end (31) of the spool core (3) abuts against the bottom of the spring seat (4) and forms left oil chamber with the adjacent spool sleeve (2) and plug (6), and the right end of the spool core (3) abuts against the spool core (81) of the electromagnetic valve (8) and forms right oil chamber with the adjacent spool sleeve (2) and electromagnetic valve (8).

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