Dual fuel common rail and rail pressure control method thereof

Abstract

The present invention provides a dual-fuel common rail pipe and a rail pressure control method thereof. The dual-fuel common rail pipe includes a common rail pipe body and a pressure balancing valve; the common rail pipe body includes a first branch pipe, a second branch pipe and a valve hole, the first branch pipe has a first inlet and a first outlet, and the second branch pipe has a second inlet and a second outlet; the pressure balancing valve includes a valve core and a spring; the valve core has a first channel and a second channel, the first inlet is connected to the first branch pipe through the first channel, the second channel is connected to the second branch pipe, and the second channel and the second inlet are connected or blocked as the valve core moves. In the embodiment of the present application, a pressure balancing valve is set, and the valve core moves in the valve hole according to the pressure difference in the two pipes and the action of the spring, and the overlapping area of ​​the second channel and the second inlet changes, thereby adjusting the feed flow rate in the second channel, and then adjusting the pressure in the second branch pipe. The pressure balancing valve is integrated into the first branch pipe and the second branch pipe, and the structure is compact, the production cost is low, and the control is accurate.

Description

Technical Field

[0001] The present application relates to engines and related technical fields, and in particular to a dual-fuel common rail and a rail pressure control method thereof. Background Art

[0002] In the engine common rail system products, a common rail pipe is set at the front end of the fuel injector, and fuel is supplied to the fuel injector by the common rail pipe, which is more conducive to the stable control of fuel pressure. With the development of combustion technology, dual-fuel combustion technology has been increasingly used. In the existing diesel and natural gas dual-fuel engine solutions, diesel and natural gas usually use two fuel common rail pipes, gas fuel is stored in the gas common rail pipe, and liquid fuel is stored in the liquid common rail pipe. The common rail pipes of the two fuels are installed separately, which requires a larger installation space and the cost of the product will be higher.

[0003] The engine requires compact design and lightweight design. Under the premise of ensuring performance, it is necessary to minimize the installation space and mass of the common rail pipe. There are also solutions in the prior art to integrate two oil rails together. As introduced in patent CN202121223946.6, the oil rail and the gas rail are integrated into a common rail pipe body, which effectively reduces the installation space requirement of the common rail pipe, reduces the mass of the common rail pipe, and reduces the production cost of the common rail pipe. In order to ensure that the diesel pressure is always higher than the natural gas pressure, as introduced in patent CN202121223946.6, a pressure balancing valve is added between the two common rail pipes. The common rail pipe and the pressure balancing valve need to be connected with an oil pipe and an air pipe. As a separate part, the pressure balancing valve needs to be located and arranged, and requires additional oil pipes and air pipes to be connected. The structure is complex, the cost is high, and the risk of leakage is increased.

[0004] In summary, the common rail system of the engine in the prior art has technical problems such as difficulty in accurately controlling the pressure of diesel and natural gas, large installation space, and high consumption of oil pipes and gas pipes. Summary of the invention

[0005] In view of the shortcomings of the existing methods, the present application proposes a dual-fuel common rail pipe and a rail pressure control method thereof to solve the technical problems existing in the prior art that the diesel and natural gas pressures are difficult to accurately control, the installation space is large, and the oil pipe and gas pipe consume more.

[0006] The present application provides a dual-fuel common rail and a rail pressure control method thereof, which are specifically as follows:

[0007] In a first aspect, an embodiment of the present application provides a dual-fuel common rail pipe, including a common rail pipe body and a pressure balancing valve;

[0008] The common rail pipe body includes a first branch pipe, a second branch pipe and a valve hole penetrating the first branch pipe and the second branch pipe, the first branch pipe has at least one first inlet and a plurality of first outlets, and the second branch pipe has at least one second inlet and a plurality of second outlets;

[0009] The pressure balancing valve comprises a valve core and a spring, wherein the valve core is embedded in the first branch pipe and the second branch pipe through the valve hole, the valve core is in contact with the inner wall of the second branch pipe through the spring, and the axial direction of the valve core is parallel to the radial direction of the first branch pipe and the second branch pipe;

[0010] The valve core has a first channel and a second channel. The first inlet is connected to the first branch pipe through the first channel. The second channel is connected to the second branch pipe. The second channel and the second inlet are connected or blocked as the valve core moves.

[0011] In some embodiments of the present application, the first branch pipe includes a fuel pipe, the second branch pipe includes a gas pipe, the first branch pipe and the second branch pipe both have a cylindrical cavity, the axial direction of the first branch pipe is parallel to the axial direction of the second branch pipe, the axial direction of the first inlet is perpendicular to the axial direction of the first branch pipe, the axial direction of the second inlet is perpendicular to the axial direction of the second branch pipe, and the axial direction of the first inlet is staggered with the axial direction of the second inlet.

[0012] In some embodiments of the present application, the end of the valve core away from the second branch pipe has a hollow blind hole, the blind hole is connected to the first inlet, the axial direction of the valve core is parallel to the axial direction of the first inlet, and the first channel passes through the blind hole to connect the two ends of the first branch pipe.

[0013] In some embodiments of the present application, the axial direction of the valve core is parallel to the elastic force direction of the spring, and the axial direction of the valve core is staggered with the axial direction of the second inlet.

[0014] In some embodiments of the present application, a first pressure sensor and a pressure relief valve are further included. The first branch pipe also has an oil return port. The pressure relief valve is connected to one end of the first branch pipe and the axial direction of the pressure relief valve is parallel to the axial direction of the first branch pipe. The pressure relief valve connects or blocks the oil return port and the second branch pipe. The sensitive element of the first pressure sensor is located at one end of the first branch pipe away from the pressure relief valve.

[0015] In some embodiments of the present application, a second pressure sensor and a plug are further included. The plug is covered on one end of the second branch pipe, and the sensitive element of the second pressure sensor is located at an end of the second branch pipe away from the plug.

[0016] In some embodiments of the present application, the valve core further has at least two sealing rings, and the two sealing rings are both sleeved between the valve core and the valve hole, and located between the first branch pipe and the second branch pipe.

[0017] In some embodiments of the present application, the common rail pipe body further has a pressure relief port, the pressure relief port is located between the first inlet and the second inlet, and the pressure relief port is communicated with the valve hole;

[0018] The valve core also has a pressure relief groove, which is located between the two sealing rings and is communicated with the pressure relief port.

[0019] In a second aspect, an embodiment of the present application further provides a rail pressure control method of a dual-fuel common rail pipe, using the dual-fuel common rail pipe as described in any embodiment of the first aspect, comprising the following steps:

[0020] Controlling the first pressure in the first branch pipe to be greater than the second pressure in the second branch pipe, and the difference between the two is within a preset range;

[0021] Wherein, when the dual-fuel common rail pipe is shut down, the valve core moves to a side away from the second branch pipe, the first inlet is connected to the first branch pipe, and the second inlet is completely misaligned with the second channel;

[0022] When the dual-fuel common rail pipe operates normally, the valve core moves to the side close to the second branch pipe, the first inlet is connected to the first branch pipe, the second inlet is connected to the second branch pipe through the second channel, and the second inlet completely overlaps with the second channel;

[0023] When the dual fuel common rail fails, the valve core moves to a side away from the second branch pipe, the first inlet is connected to the first branch pipe, the second inlet is connected to the second branch pipe through the second channel, and the second inlet partially overlaps with the second channel.

[0024] In some embodiments of the present application, the preset range is a difference between the first pressure and the second pressure of not less than 10 bar;

[0025] When the dual-fuel common rail pipe is shut down, the first pressure and the second pressure are both zero;

[0026] When the dual fuel common rail operates normally, the difference between the first pressure and the second pressure is not less than 10 bar;

[0027] When the dual fuel common rail fails, the difference between the first pressure and the second pressure is less than 10 bar.

[0028] The beneficial technical effects brought by the technical solution provided by the embodiment of the present application include: the embodiment of the present application sets a pressure balance valve, the pressure balance valve is connected to the first branch pipe and the second branch pipe respectively, the valve core moves in the valve hole according to the pressure difference in the two pipes and the action of the spring, the first channel is always connected to the first inlet, the feed flow rate in the first channel and the pressure in the first branch pipe tend to be stable; with the movement of the valve core, the overlap area of ​​the second channel and the second inlet changes, including complete misalignment, partial overlap and complete overlap, so as to adjust the feed flow rate in the second channel, and then adjust the pressure in the second branch pipe, so as to achieve the control of the pressure difference between the first branch pipe and the second branch pipe to meet the preset range. The first branch pipe and the second branch pipe are integrated through the common rail pipe body, and the pressure balance valve is embedded in the common rail pipe body. Compared with the external pressure balance valve in the prior art, the pressure balance valve in this embodiment is integrated in the first branch pipe and the second branch pipe, and there is no need to set a separate shell to occupy the installation space, and there is no need to connect the common rail pipe by setting additional oil pipes and gas pipes. The structure is compact, the production cost is low, and the control is accurate.

[0029] Additional aspects and advantages of the present application will be partially given in the following description, which will become apparent from the following description, or will be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0031] Figure 1 A cross-sectional schematic diagram of a dual-fuel common rail pipe in an embodiment of the present application;

[0032] Figure 2 This is a schematic diagram of the structure of a dual-fuel common rail pipe in an embodiment of the present application;

[0033] Figure 3 A front cross-sectional view of a pressure balancing valve in an embodiment of the present application;

[0034] Figure 4 It is a side sectional view of a pressure balancing valve in an embodiment of the present application.

[0035] Reference numerals:

[0036] 1-pressure balancing valve, 2-first branch pipe, 3-second branch pipe;

[0037] 11-valve core, 12-spring, 13-first channel, 14-second channel, 15-sealing ring, 16-pressure relief port, 17-pressure relief groove;

[0038] 21-first inlet, 22-first outlet, 23-first pressure sensor, 24-pressure relief valve, 25-oil return port;

[0039] 31 - second inlet, 32 - second outlet, 33 - second pressure sensor, 34 - plug. DETAILED DESCRIPTION

[0040] The embodiments of the present application are described below in conjunction with the drawings in the present application. It should be understood that the implementation methods described below in conjunction with the drawings are exemplary descriptions for explaining the technical solutions of the embodiments of the present application and do not constitute a limitation on the technical solutions of the embodiments of the present application.

[0041] Those skilled in the art will appreciate that, unless expressly stated otherwise, the singular forms "a", "an", "above", and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present application refers to the presence of the features, integers, steps, operations, elements, and / or components, but does not exclude the implementation of other features, information, data, steps, operations, elements, components, and / or combinations thereof supported by the technical field. It should be understood that when we refer to an element as being "connected" to another element, the one element may be directly connected to the other element, or it may refer to the one element and the other element establishing a connection relationship through an intermediate element. In addition, the "connection" used herein may include a wireless connection.

[0042] In order to make the purpose, technical solution and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings. It should be noted that the following implementation methods can refer to, learn from or combine with each other, and the same terms, similar features and similar implementation steps in different implementation methods will not be described repeatedly.

[0043] The present application provides a dual-fuel common rail and a rail pressure control method thereof, which are specifically as follows:

[0044] In a first aspect, an embodiment of the present application provides a dual fuel common rail pipe, such as Figure 1 to Figure 4 As shown, Figure 1 A cross-sectional schematic diagram of a dual-fuel common rail pipe in an embodiment of the present application; Figure 2 This is a schematic diagram of the structure of a dual-fuel common rail pipe in an embodiment of the present application; Figure 3 A front cross-sectional view of a pressure balancing valve in an embodiment of the present application; Figure 4 It is a side sectional view of a pressure balancing valve in an embodiment of the present application.

[0045] The dual-fuel common rail pipe comprises a common rail pipe body and a pressure balancing valve 1.

[0046] The common rail pipe body includes a first branch pipe 2, a second branch pipe 3 and a valve hole penetrating the first branch pipe 2 and the second branch pipe 3. The first branch pipe 2 has at least one first inlet 21 and multiple first outlets 22. The second branch pipe 3 has at least one second inlet 31 and multiple second outlets 32.

[0047] The pressure balancing valve 1 includes a valve core 11 and a spring 12. The valve core 11 is embedded in the first branch pipe 2 and the second branch pipe 3 through the valve hole. The valve core 11 abuts against the inner wall of the second branch pipe 3 through the spring 12. The axial direction of the valve core 11 is parallel to the radial direction of the first branch pipe 2 and the second branch pipe 3.

[0048] The valve core 11 has a first channel 13 and a second channel 14 . The first inlet 21 is connected to the first branch pipe 2 through the first channel 13 . The second channel 14 is connected to the second branch pipe 3 . The second channel 14 and the second inlet 31 are connected or blocked as the valve core 11 moves.

[0049] In the embodiment of the present application, a pressure balancing valve 1 is provided, and the pressure balancing valve 1 is connected to the first branch pipe 2 and the second branch pipe 3 respectively. According to the pressure difference in the two pipes and the action of the spring 12, the valve core 11 moves in the valve hole, the first channel 13 and the first inlet 21 are always connected, and the feed flow rate in the first channel 13 and the pressure in the first branch pipe 2 tend to be stable; as the valve core 11 moves, the overlapping area between the second channel 14 and the second inlet 31 changes, including complete misalignment, partial overlap and complete overlap, so as to adjust the feed flow rate in the second channel 14, and then adjust the pressure in the second branch pipe 3, so as to achieve the control of the pressure difference between the first branch pipe 2 and the second branch pipe 3 to meet the preset range. The first branch pipe 2 and the second branch pipe 3 are integrated through the common rail pipe body, and the pressure balancing valve 1 is embedded in the common rail pipe body. Compared with the external pressure balancing valve 1 in the prior art, the pressure balancing valve 1 in the present embodiment is integrated into the first branch pipe 2 and the second branch pipe 3. There is no need to set a separate shell to occupy the installation space, and there is no need to set additional oil pipes and air pipes to connect the common rail pipe. The structure is compact, the production cost is low, and the control is accurate.

[0050] In some embodiments of the present application, the first branch pipe 2 includes a fuel pipe, the second branch pipe 3 includes a gas pipe, the first branch pipe 2 and the second branch pipe 3 both have a cylindrical cavity, the axial direction of the first branch pipe 2 is parallel to the axial direction of the second branch pipe 3, the axial direction of the first inlet 21 is perpendicular to the axial direction of the first branch pipe 2, the axial direction of the second inlet 31 is perpendicular to the axial direction of the second branch pipe 3, and the axial direction of the first inlet 21 is staggered with the axial direction of the second inlet 31.

[0051] In this embodiment, the first branch pipe 2 is a fuel pipe, and the second branch pipe 3 is a gas pipe. Accordingly, the first inlet 21 is an oil inlet, and the second inlet 31 is a plurality of air inlets arranged at intervals along the axial direction of the first branch pipe 2. The axial direction of the first inlet 21 and the axial direction of the second inlet 31 are staggered with each other, so that the opening and closing state of the second inlet 31 can be changed when the first inlet 21 is always open.

[0052] It can be understood that, in the above-mentioned embodiments and some of the following embodiments, the first branch pipe 2 is a fuel pipe, the second branch pipe 3 is a gas pipe, the first inlet 21 is an oil inlet, and the second inlet 31 is an air inlet. In fact, the first branch pipe 2 is a gas pipe, the second branch pipe 3 is a fuel pipe, the first inlet 21 is an air inlet, and the second inlet 31 is a plurality of oil inlets arranged at intervals along the axial direction of the second branch pipe 3. The beneficial effects of the present application can also be achieved and belong to the protection scope of the present application.

[0053] In some embodiments of the present application, the end of the valve core 11 away from the second branch pipe 3 has a hollow blind hole, the blind hole is connected to the first inlet 21, the axial direction of the valve core 11 is parallel to the axial direction of the first inlet 21, and the first channel 13 passes through the blind hole to connect the two ends of the first branch pipe 2.

[0054] In one embodiment, the valve core 11 is installed by the air inlet and is sequentially embedded in the first branch pipe 2 and the second branch pipe 3. The first inlet 21, the valve core 11 and the blind hole are coaxial, and the oil supply device is connected to the end of the blind hole away from the second branch pipe 3, and the fuel enters the valve core 11 from one end of the blind hole. Since the valve core 11 is embedded, the first branch pipe 2 is divided into two independent chambers. The first channel 13 is the fuel channel, and the first channel 13 runs through the valve core 11. The first channel 13 passes through the end of the blind hole close to the second branch pipe 3 and connects the two chambers of the first branch pipe 2. The fuel enters the first branch pipe 2 from the valve core 11.

[0055] In this embodiment, the first channel 13 may be an annular groove, the inner wall opening of the annular groove is connected to the blind hole, and the outer side of the annular groove is open and connected to the first branch pipe 2. The first channel 13 may also be a multi-branched groove in the shape of a straight line, a T-shape, a Y-shape, or a cross, wherein at least two branches face the two chambers respectively.

[0056] In some embodiments of the present application, the axial direction of the valve core 11 is parallel to the elastic force direction of the spring 12 , and the axial direction of the valve core 11 is staggered with the axial direction of the second inlet 31 .

[0057] In this embodiment, the moving direction of the valve core 11 is interlaced with the axial direction of the second inlet 31, and the following description takes the case where the two are perpendicular to each other as an example. A groove is provided at one end of the valve core 11 facing the second branch pipe 3, and the groove is used to accommodate the spring 12. The two ends of the spring 12 are in contact with the bottom surface of the groove of the valve core 11 and the inner wall of the second branch pipe 3 respectively. When the valve core 11 is located at the stroke limit close to the side of the second branch pipe 3, the end surface of the valve core 11 is in direct contact with the inner wall of the second branch pipe 3, the spring 12 shrinks in the groove, the overlap area of ​​the second channel 14 and the second inlet 31 is the largest, the intake speed in the second channel 14 is the largest, and the pressure in the second branch pipe 3 is the largest.

[0058] When the opening area of ​​the second channel 14 is greater than or equal to the opening area of ​​the second inlet 31 , the second opening completely overlaps with the second channel 14 , that is, the second opening is covered by the opening of the second channel 14 .

[0059] When the opening area of ​​the second channel 14 is smaller than the opening area of ​​the second inlet 31 , the second channel 14 completely overlaps with the second opening, that is, the second channel 14 is covered by the second opening.

[0060] In this embodiment, the second channel 14 can be an annular groove, the inner side wall of the annular groove is closed, the valve core 11 is embedded to separate the second branch pipe 3 into two independent chambers, the second channel 14 is a gas channel, the outer side of the annular groove is open and communicates with the two chambers and the second inlet 31. The gas supply device is connected to the second inlet 31, the gas enters the valve core 11 from the second inlet 31, and the gas in the valve core 11 enters the second branch pipe 3. The second channel 14 can also be a multi-branched groove in a T-shape, a Y-shape, or a cross shape, wherein at least three forks face the two chambers and the second inlet 31 respectively.

[0061] In some embodiments of the present application, a first pressure sensor 23 and a pressure relief valve 24 are further included. The first branch pipe 2 also has an oil return port 25. The pressure relief valve 24 is connected to one end of the first branch pipe 2 and the axial direction of the pressure relief valve 24 is parallel to the axial direction of the first branch pipe 2. The pressure relief valve 24 connects or blocks the oil return port 25 and the second branch pipe 3. The sensitive element of the first pressure sensor 23 is located at one end of the first branch pipe 2 away from the pressure relief valve 24.

[0062] In this embodiment, the first pressure sensor 23 is a fuel rail pressure sensor. The first pressure sensor 23 is installed at one end of the first branch pipe 2, and mainly measures the fuel pressure in the first branch pipe 2. The instantaneous fuel pressure in the rail is measured through the silicon membrane in the sensitive element, and the sensor element in the sensitive element is installed on the silicon membrane to convert the fuel pressure into a voltage output.

[0063] The first branch pipe 2 is provided with an oil return port 25 and a pressure relief valve 24. When the pressure in the first branch pipe 2 exceeds a certain value, the pressure relief valve 24 will automatically open, and the fuel therein can flow back to the fuel supply device through the oil return port 25 to release the pressure, so as to keep the pressure in the diesel cavity stable, prevent the common rail system from being damaged by excessive pressure, and protect the safety of the entire common rail system.

[0064] The specific working process of the pressure relief valve 24 is as follows: when the pressure in the first branch pipe 2 rises to the opening pressure set by the pressure relief valve 24, the valve flap of the pressure relief valve 24 is lifted upward under the action of the fuel pressure, opening the pressure relief channel, so that the excess fuel flows back to the fuel tank through the oil return port 25. If the pressure relief valve 24 fails to open, or the opening pressure is set incorrectly, the pressure in the diesel chamber will be too high, affecting the normal operation of the common rail system. If the pressure cannot be reduced to a normal value, the common rail system may be damaged.

[0065] In some embodiments of the present application, a second pressure sensor 33 and a plug 34 are further included. The plug 34 is covered on one end of the second branch pipe 3 , and the sensitive element of the second pressure sensor 33 is located at an end of the second branch pipe 3 away from the plug 34 .

[0066] The second pressure sensor 33 is a gas pressure sensor.

[0067] The second pressure sensor 33 uses piezoelectric material as a sensitive element to convert pressure signals into electrical signals, which are then processed by circuits to measure pressure. Commonly used piezoelectric materials include quartz, potassium sodium tartrate, and diammonium phosphate.

[0068] The plug 34 is a valve in the second branch pipe 3, which can adjust the pressure difference between the inside and outside of the second branch pipe 3, and can also control the pressure of the gas. In some application scenarios, it is necessary to control the pressure of the gas to ensure the normal operation of the system. By adjusting the pressure through the plug 34, the influence of excessive or low pressure on the system can be avoided.

[0069] In some embodiments of the present application, the valve core 11 further has at least two sealing rings 15 , and the two sealing rings 15 are both sleeved between the valve core 11 and the valve hole, and located between the first branch pipe 2 and the second branch pipe 3 .

[0070] In this embodiment, a sealing ring 15 is used between the first branch pipe 2 and the second branch pipe 3 to ensure that the fuel oil and the gas will not mix with each other, thereby improving the sealing effect.

[0071] In some embodiments of the present application, the common rail pipe body further has a pressure relief port 16, the pressure relief port 16 is located between the first inlet 21 and the second inlet 31, and the pressure relief port 16 is communicated with the valve hole;

[0072] The valve core 11 further has a pressure relief groove 17 , which is located between the two sealing rings 15 , and is communicated with the pressure relief port 16 .

[0073] In this embodiment, an annular pressure relief groove 17 structure and a fuel / gas pressure relief port 16 are added between the two sealing rings 15 to ensure that in the event of failure of the sealing ring 15, the fuel or gas will flow out of the pressure relief port 16 and will not mix with each other in the fuel chamber.

[0074] In a second aspect, an embodiment of the present application further provides a rail pressure control method of a dual-fuel common rail pipe, using the dual-fuel common rail pipe as described in any embodiment of the first aspect, comprising the following steps:

[0075] Control the first pressure in the first branch pipe 2 to be greater than the second pressure in the second branch pipe 3, and the difference between the two is within a preset range;

[0076] When the dual-fuel common rail is shut down, the valve core 11 moves to a side away from the second branch pipe 3, the first inlet 21 is connected to the first branch pipe 2, and the second inlet 31 is completely misaligned with the second channel 14;

[0077] When the dual-fuel common rail operates normally, the valve core 11 moves to the side close to the second branch pipe 3, the first inlet 21 is connected to the first branch pipe 2, the second inlet 31 is connected to the second branch pipe 3 through the second channel 14, and the second inlet 31 completely overlaps with the second channel 14;

[0078] When the dual fuel common rail fails, the valve core 11 moves away from the second branch pipe 3 , the first inlet 21 is connected to the first branch pipe 2 , the second inlet 31 is connected to the second branch pipe 3 through the second channel 14 , and the second inlet 31 partially overlaps with the second channel 14 .

[0079] In some embodiments of the present application, the preset range is a difference between the first pressure and the second pressure of not less than 10 bar;

[0080] When the dual-fuel common rail pipe is shut down, the first pressure and the second pressure are both zero;

[0081] When the dual fuel common rail operates normally, the difference between the first pressure and the second pressure is not less than 10 bar;

[0082] When the dual fuel common rail fails, the difference between the first pressure and the second pressure is less than 10 bar.

[0083] In this embodiment, in the step of dual fuel common rail failure, the difference between the first pressure and the second pressure is less than 10 bar, and the valve core 11 continues to move toward the side away from the second branch pipe 3. At this time, the overlapping area between the second inlet 31 and the second channel 14 gradually decreases, that is, the flow cross-sectional area in the second inlet 31 and the second channel 14 bracket gradually decreases from the maximum opening, the fuel flow rate in the second channel 14 decreases, and the pressure in the second branch pipe 3 decreases until the difference between the first pressure and the second pressure is greater than or equal to 10 bar again.

[0084] Compared with the prior art, the application of the embodiments of the present application can at least achieve the following beneficial effects: the embodiment of the present application sets a pressure balancing valve 1, and the pressure balancing valve 1 is connected to the first branch pipe 2 and the second branch pipe 3 respectively. According to the pressure difference in the two pipes and the action of the spring 12, the valve core 11 moves in the valve hole, the first channel 13 and the first inlet 21 are always connected, and the feed flow rate in the first channel 13 and the pressure in the first branch pipe 2 tend to be stable; as the valve core 11 moves, the overlapping area between the second channel 14 and the second inlet 31 changes, including complete misalignment, partial overlap and complete overlap, thereby adjusting the feed flow rate in the second channel 14, and then adjusting the pressure in the second branch pipe 3, so as to control the pressure difference between the first branch pipe 2 and the second branch pipe 3 to meet the preset range. The first branch pipe 2 and the second branch pipe 3 are integrated through the common rail pipe body, and the pressure balancing valve 1 is embedded in the common rail pipe body. Compared with the external pressure balancing valve 1 in the prior art, the pressure balancing valve 1 in the present embodiment is integrated into the first branch pipe 2 and the second branch pipe 3. There is no need to set a separate shell to occupy the installation space, and there is no need to set additional oil pipes and air pipes to connect the common rail pipe. The structure is compact, the production cost is low, and the control is accurate.

[0085] In the description of the present application, the directions or positional relationships indicated by words such as "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the exemplary directions or positional relationships shown in the accompanying drawings. They are for the convenience of describing or simplifying the description of the embodiments of the present application, and do not indicate or imply that the referred device or component must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present application.

[0086] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0087] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0088] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0089] Those skilled in the art will appreciate that the various operations, methods, steps, measures, and schemes in the processes discussed in this application may be alternated, altered, combined, or deleted. Further, other steps, measures, and schemes in the various operations, methods, and processes discussed in this application may also be alternated, altered, rearranged, decomposed, combined, or deleted. Further, the steps, measures, and schemes in the prior art that are similar to those disclosed in this application may also be alternated, altered, rearranged, decomposed, combined, or deleted.

[0090] It should be understood that, although the steps in the flowchart of the accompanying drawings are displayed in sequence as indicated by the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least a part of the steps in the flowchart of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be executed in turn or alternately with other steps or at least a part of the sub-steps or stages of other steps.

[0091] The above is only a partial implementation method of the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the technical concept of the scheme of the present application, other similar implementation methods based on the technical ideas of the present application are also within the protection scope of the embodiments of the present application.

Claims

1. A dual fuel common rail pipe, characterized in that: It includes a common rail pipe body and a pressure balancing valve; The common rail pipe body includes a first branch pipe, a second branch pipe and a valve hole penetrating the first branch pipe and the second branch pipe, the first branch pipe has at least one first inlet and a plurality of first outlets, and the second branch pipe has at least one second inlet and a plurality of second outlets; The pressure balancing valve comprises a valve core and a spring, wherein the valve core is embedded in the first branch pipe and the second branch pipe through the valve hole, the valve core is in contact with the inner wall of the second branch pipe through the spring, and the axial direction of the valve core is parallel to the radial direction of the first branch pipe and the second branch pipe; The valve core has a first channel and a second channel, the first inlet is connected to the first branch pipe through the first channel, the first channel is always connected to the first inlet, the second channel is connected to the second branch pipe, and the second channel and the second inlet are connected or blocked due to the change of the overlapping area between the second channel and the second inlet as the valve core moves; The first branch pipe includes a fuel pipe, the second branch pipe includes a gas pipe, and one end of the valve core away from the second branch pipe has a hollow blind hole, and the blind hole is communicated with the first inlet.

2. The dual fuel common rail pipe according to claim 1, characterized in that: The first branch pipe and the second branch pipe both have a cylindrical cavity, the axial direction of the first branch pipe is parallel to the axial direction of the second branch pipe, the axial direction of the first inlet is perpendicular to the axial direction of the first branch pipe, the axial direction of the second inlet is perpendicular to the axial direction of the second branch pipe, and the axial direction of the first inlet is staggered with the axial direction of the second inlet.

3. The dual fuel common rail pipe according to claim 2, characterized in that: The axial direction of the valve core is parallel to the axial direction of the first inlet, and the first channel passes through the blind hole to communicate with both ends of the first branch pipe.

4. The dual fuel common rail pipe according to claim 2, characterized in that: The axial direction of the valve core is parallel to the elastic force direction of the spring, and the axial direction of the valve core is staggered with the axial direction of the second inlet.

5. The dual fuel common rail pipe according to claim 1, characterized in that: It also includes a first pressure sensor and a pressure relief valve. The first branch pipe also has an oil return port. The pressure relief valve is connected to one end of the first branch pipe and the axial direction of the pressure relief valve is parallel to the axial direction of the first branch pipe. The pressure relief valve connects or blocks the oil return port and the second branch pipe. The sensitive element of the first pressure sensor is located at one end of the first branch pipe away from the pressure relief valve.

6. The dual fuel common rail pipe according to claim 1, characterized in that: It also includes a second pressure sensor and a plug. The plug is covered on one end of the second branch pipe. The sensitive element of the second pressure sensor is located at one end of the second branch pipe away from the plug.

7. The dual fuel common rail pipe according to claim 1, characterized in that: The valve core also has at least two sealing rings, and the two sealing rings are both sleeved between the valve core and the valve hole, and located between the first branch pipe and the second branch pipe.

8. The dual fuel common rail pipe according to claim 7, characterized in that: The common rail pipe body further has a pressure relief port, the pressure relief port is located between the first inlet and the second inlet, and the pressure relief port is communicated with the valve hole; The valve core also has a pressure relief groove, which is located between the two sealing rings and is communicated with the pressure relief port.

9. A rail pressure control method for a dual-fuel common rail, characterized in that: The dual fuel common rail pipe according to any one of claims 1 to 8 comprises the following steps: Controlling the first pressure in the first branch pipe to be greater than the second pressure in the second branch pipe, and the difference between the two is within a preset range; Wherein, when the dual-fuel common rail pipe is shut down, the valve core moves to a side away from the second branch pipe, the first inlet is connected to the first branch pipe, and the second inlet is completely misaligned with the second channel; When the dual-fuel common rail pipe operates normally, the valve core moves to the side close to the second branch pipe, the first inlet is connected to the first branch pipe, the second inlet is connected to the second branch pipe through the second channel, and the second inlet completely overlaps with the second channel; When the dual fuel common rail fails, the valve core moves to a side away from the second branch pipe, the first inlet is connected to the first branch pipe, the second inlet is connected to the second branch pipe through the second channel, and the second inlet partially overlaps with the second channel.

10. The rail pressure control method according to claim 9, characterized in that: The preset range is that the difference between the first pressure and the second pressure is not less than 10 bar; When the dual-fuel common rail pipe is shut down, the first pressure and the second pressure are both zero; When the dual fuel common rail operates normally, the difference between the first pressure and the second pressure is not less than 10 bar; When the dual fuel common rail fails, the difference between the first pressure and the second pressure is less than 10 bar.

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