Methanol fuel engine fuel supply pipe system with heating function

Abstract

The methanol fuel engine fuel supply pipe system with the heating function comprises a plurality of three-layer pipes, a plurality of switching blocks and a plurality of limiting plates, each three-layer pipe comprises an inner pipe, a middle pipe, an outer pipe and two arc-shaped PTC heating plates embedded into a peripheral ring groove of the inner pipe, and the middle pipe is inserted into the outer pipe and fixedly connected with the outer pipe into a whole. An outer pipe annular cavity serving as a nitrogen channel is formed between an inner hole of the outer pipe and the peripheral face of the middle pipe, a center hole of the adapter block is communicated with the inner pipe to serve as a methanol fuel channel, and the two ends of the three-layer pipe are inserted into a pipe system which is fixedly connected through the adapter block and the limiting plate to form an integral structure. According to the methanol fuel engine, the manufacturing cost of the engine is remarkably reduced, methanol fuel in the inner pipe is heated after the arc-shaped PTC heating plate is powered on, the low-temperature cold start performance of the methanol fuel engine is effectively improved, and the safety performance of the methanol fuel engine and the purging efficiency of the methanol fuel are comprehensively improved.

Description

Technical Field

[0001] The invention relates to a fuel supply system for a new energy engine, in particular to a fuel supply pipe system for a methanol fuel engine capable of heating methanol fuel, belonging to the technical field of new energy engines. Background Art

[0002] Methanol fuel has great potential for application in the field of new energy engines due to its advantages of being clean, environmentally friendly and widely available. However, its high latent heat of vaporization has brought many difficult problems to the practical application of engines.

[0003] In terms of low-temperature cold start, whether it is direct injection or manifold injection, methanol fuel faces severe challenges. When a methanol fuel engine is cold started, the methanol fuel injected into the engine intake port is not vaporized well and often enters the cylinder in liquid form. This will not only dilute the lubricating oil and affect the engine's lubrication system, but also reduce the temperature in the cylinder at medium and low loads, causing the flame propagation front to quench on the cylinder wall, causing incomplete combustion, resulting in reduced performance of the methanol fuel engine and increased pollutant emissions.

[0004] At the same time, the toxicity of methanol fuel cannot be ignored. It is extremely harmful to the human nervous system and blood system. Once methanol leaks during the operation of the new fuel engine, it is very likely to cause serious safety accidents, threatening the life and health of personnel and the safety of the surrounding environment. Even if it is not burned, methanol gas volatilizes or accidentally splashes on the surface of human skin, which will also cause great harm to the human body. In order to solve the problem of low-temperature cold start of methanol fuel engines, there are two main improvement measures: one is to use an external auxiliary fuel tank and add an injection system for ignition. This improvement measure is costly, the engine structure becomes more complicated, and the difficulty of later maintenance increases; the other is to preheat the methanol fuel. Most of the fuel is heated by an external heater before entering the engine. This improvement measure not only requires an additional preheating system, which leads to an increase in engine manufacturing costs; but also has low heating efficiency, and due to the toxicity of methanol fuel, once a leak occurs, the consequences are disastrous. In response to the methanol leakage problem, the existing improvement measure is to set an inert gas purge layer in the engine fuel supply pipeline to timely inertize and purge the leaked methanol, but the purge efficiency of this improvement measure is low, which is difficult to meet the needs of high efficiency and safety.

[0005] In addition, the fluidity of methanol fuel in the fuel supply pipeline is greatly affected by temperature. At lower temperatures, the viscosity of methanol fuel increases and the fluidity decreases, which may lead to incomplete purging. By increasing the pipeline temperature (usually between 20°C and 40°C), the good fluidity of methanol fuel is maintained, the efficiency of nitrogen purging is improved, and the residual methanol and impurities in the pipeline are ensured to be completely removed.

[0006] How to effectively improve the low-temperature cold start performance of methanol fuel engines, significantly reduce the risk of fuel splashing and leakage of methanol fuel engines, and comprehensively improve the safety performance of methanol fuel engines and the methanol fuel purging efficiency has become a key technical problem that technical personnel in this field need to overcome urgently. Summary of the invention

[0007] The purpose of the present invention is to provide a fuel supply pipe system for a methanol fuel engine with a heating function, so as to effectively improve the low-temperature cold start performance of the methanol fuel engine.

[0008] The present invention is achieved through the following technical solutions:

[0009] A fuel supply pipe system for a methanol fuel engine with a heating function comprises a plurality of three-layer pipes, adapter blocks respectively used to connect the three-layer pipes and limit plates respectively fixed at both ends of the adapter blocks, the three-layer pipe comprises an inner pipe, a middle pipe, an outer pipe and two arc-shaped PTC heating plates, the inner pipe is a pipe fitting with stepped flanges at both ends and an annular groove recessed in the middle, the two arc-shaped PTC heating plates are respectively embedded in the annular grooves, and the radial end faces of the arc-shaped PTC heating plates are respectively limited by axial limit strips symmetrically arranged on the outer peripheral surface of the inner pipe; the inner pipe is inserted into the middle pipe, the stepped flanges at both ends of the inner pipe are threadedly connected to the two ends of the inner hole of the middle pipe, and are coated with sealant, a middle pipe annular cavity with two ends closed is provided between the outer peripheral surface of the arc-shaped PTC heating plate and the inner hole of the middle pipe; two pairs of outwardly extending outer protrusions are arranged at intervals on the radial upper and lower sides of the outer peripheral surface of the middle pipe, The middle tube is inserted into the outer tube and is sealed by an O-ring embedded in the top surface of the outer protrusion seat. Outer tube flanges are respectively provided at the ends of the outer tube; connecting screws are respectively passed through the outer tube and screwed into the corresponding outer protrusion seats to fix the outer tube and the middle tube into one; an outer tube annular cavity serving as a nitrogen channel is provided between the inner hole of the outer tube and the outer circumference of the middle tube; the two ends of the three-layer tube are respectively inserted into one end of the corresponding adapter block, and the limit plates are respectively positioned on the ends of the outer tube and fixed on the corresponding vertical end faces of the adapter blocks, so that several three-layer tubes are respectively fixedly connected into an integral structure of the pipe system through the adapter blocks and the limit plates; the oil pipe joints of the alcohol injector are respectively fixed on the adapter blocks, and the center holes of the adapter blocks are connected to the inner tube serving as the methanol fuel channel; the adapter blocks at both ends of the fuel supply pipe system are respectively connected to the methanol station and the nitrogen station through corresponding double-walled pipes.

[0010] The purpose of the present invention can be further achieved by the following technical measures.

[0011] Furthermore, the adapter block is a cube, and the centers of the vertical end faces at both longitudinal ends of the adapter block are respectively provided with annular grooves with an inner diameter larger than the center hole of the adapter block, and positioning circular tubes are respectively extended outward from the central axis of the annular groove, and the inner diameter of the positioning circular tube is larger than the aperture of the center hole of the adapter block; the centers of the two vertex angle inclined surfaces of the adapter block are respectively provided with threaded holes for the oil pipe joint of the alcohol injector and threaded holes for the pressure-stabilizing valve, and the inner ends of the threaded holes for the oil pipe joint of the alcohol injector and the threaded holes for the pressure-stabilizing valve intersect perpendicularly with the center hole of the adapter block respectively; a plurality of transverse holes are distributed on the bottom surface of the annular groove, and the two ends of the transverse holes respectively penetrate the bottom surface of the annular groove and the outer Tube annular cavity; when the axial ends of the adapter block are respectively connected to the corresponding three-layer tube ends, the positioning circular tubes are respectively embedded in the annular grooves of the stepped flange end faces of the corresponding inner tube ends, and the ends of the outer tube, the middle tube and the inner tube are respectively against the bottom faces of the corresponding annular grooves, so that the two ends of the three-layer tube are respectively positioned in the vertical end faces corresponding to the adapter block, and the two ends of the multiple transverse holes are respectively communicated with the annular cavity of the outer tube of the three-layer tube, and the center hole of the adapter block is communicated with the inner tube; the outer tube ends are respectively inserted into the annular grooves, and the limit plates are respectively fixed on the corresponding vertical end faces of the adapter blocks, so that the three-layer tube is fixedly connected into an integral structure through the adapter blocks.

[0012] Furthermore, the limit plate is formed by connecting two half-limiting plates, and the adjacent sides of the half-limiting plates are respectively provided with semicircular notches matching the circumferential surface of the outer tube flange, the semicircular notches are radially provided with semicircular positioning grooves, and the outer tube flange is respectively provided with radially extending positioning ring ribs; when the two half-limiting plates are positioned on the outer tube flange, the positioning ring ribs are respectively embedded in the corresponding semicircular positioning grooves, and the semicircular notches rest on the outer circumferential surface of the outer tube flange, and the fastening screws pass through the four corners of the limit plate spliced ​​by the two half-limiting plates, and are screwed into the corresponding vertical end faces of the adapter blocks, so that the two ends of the multiple three-layer tubes are fixedly connected into an integral structure of the pipe system through the adapter blocks and the limit plates.

[0013] Furthermore, the power cord at the end of the arc-shaped PTC heating plate passes through one end of the annular cavity of the middle tube and is then led to the outside of the outer tube through the wiring tube; the inner end of the wiring tube crosses the outer tube and the middle tube in turn and is welded to the outer tube, the inside of the wiring tube is sealed with sealant, the outer end of the wiring tube is closed with a screw cover, and the power cord is led out from the center hole of the screw cover.

[0014] Furthermore, two inner tube radial O-rings are installed in the annular groove of the step flange end face, and the positioning round tubes are respectively inserted into the annular grooves of the step flange end faces of the corresponding inner tube ends; the step flange end face is equipped with an inner tube axial O-ring, and the outer tube end is equipped with an outer tube radial O-ring.

[0015] The present invention adopts a three-layer tube with an inner tube, a middle tube and an outer tube as a fuel supply tube for a methanol fuel engine, and embeds two arc-shaped PTC heating plates into a ring groove in the middle of the inner tube. After the arc-shaped PTC heating plate is powered on, the methanol fuel in the inner tube is instantly heated to 40°C in 3 seconds, and no external auxiliary fuel tank or fuel injection system is required for ignition; nor is it necessary to heat the methanol fuel with an external heater before inputting it into the engine. The structure is compact and the reliability is high, which significantly reduces the manufacturing cost of the methanol fuel engine. The arc-shaped PTC heating plate of the present invention heats the methanol fuel in the inner tube after being powered on, which effectively improves the low-temperature cold start performance of the methanol fuel engine, and comprehensively improves the safety performance and methanol fuel purge efficiency of the methanol fuel engine.

[0016] Advantages and features of the present invention will be illustrated and explained by the following non-limiting description of preferred embodiments thereof, which are given by way of example only with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a three-dimensional structural diagram of the present invention;

[0018] Figure 2 It is a front view of the present invention;

[0019] Figure 3 yes Figure 2 AA enlarged cross-sectional view;

[0020] Figure 4 It is an enlarged stereogram of the adapter block;

[0021] Figure 5 yes Figure 3 BB cross-sectional view;

[0022] Figure 6 yes Figure 4 C-direction view;

[0023] Figure 7 yes Figure 6 DD cross-sectional view;

[0024] Figure 8 It is the main view of the limit plate;

[0025] Fig. 9 yes Figure 2 EE cross-sectional enlarged view. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings and an embodiment of a methanol fuel 6-cylinder engine.

[0027] like Figures 1 to 9As shown, this embodiment includes 5 three-layer tubes 1, adapter blocks 2 respectively used to connect the three-layer tubes 1, and limit plates 3 respectively fixed at both ends of the adapter blocks. The three-layer tube 1 includes an inner tube 11, a middle tube 12, an outer tube 13, and two arc-shaped PTC heating plates 14. The inner tube 11 is a pipe with stepped flanges 111 at both ends and an annular groove 112 recessed in the middle. The two arc-shaped PTC heating plates 14 are respectively embedded in the annular grooves 112, and the radial end faces of the arc-shaped PTC heating plates 14 are respectively limited by axial limit strips 114 symmetrically arranged on the outer peripheral surface of the inner tube 11. The inner tube 11 is inserted into the middle tube 12, and the stepped flanges 111 at both ends of the inner tube are threadedly connected to the two ends of the inner hole of the middle tube 12, and are coated with sealant. A middle tube annular cavity 121 with closed ends is provided between the outer peripheral surface of the arc-shaped PTC heating plate 14 and the inner hole of the middle tube 12. After the arc-shaped PTC heating plate is powered on, it can instantly heat the methanol fuel in the inner tube to 40°C in 3 seconds.

[0028] like Figure 3 As shown, two pairs of outwardly extending outer protrusions 122 are arranged at intervals on the radial upper and lower sides of the outer circumference of the middle tube 12. The middle tube 12 is inserted into the outer tube 13 and sealed by the outer protrusion O-ring 123 embedded in the top surface of the outer protrusion 122. The ends of the outer tube 13 are respectively provided with outer tube flanges 131, and the connecting screws 4 are respectively passed through the outer tube 13 and screwed into the corresponding outer protrusions 122 to fix the outer tube 13 and the middle tube 12 into one body. An outer tube annular cavity 132 is provided between the inner hole of the outer tube 13 and the outer circumference of the middle tube 14 as a nitrogen passage.

[0029] like Figures 4 to 7As shown, the adapter block 2 is a cube, and the centers of the vertical end faces at both ends of the adapter block are respectively provided with annular grooves 22 with an inner diameter greater than the diameter of the center hole 21 of the adapter block, and the center axis of the annular groove 22 extends outwardly with positioning circular tubes 221, and the inner diameter of the positioning circular tubes 221 is greater than the aperture of the center hole 21 of the adapter block. The centers of the two vertex angle inclined surfaces of the adapter block 2 are respectively provided with threaded holes 23 of the oil pipe joint of the alcohol injector and threaded holes 24 of the pressure regulating valve, and the inner ends of the threaded holes 23 of the oil pipe joint of the alcohol injector and the inner ends of the threaded holes 24 of the pressure regulating valve are respectively intersected with the center hole 21 of the adapter block vertically. One end of the pressure regulating valve is respectively screwed on the threaded holes 24 of the pressure regulating valve, and when the methanol fuel engine generates pressure fluctuations due to load changes, the pressure regulating valve can stabilize the pressure fluctuations in the inner tube 11. A plurality of transverse holes 222 are distributed on the bottom surface of the annular groove 22, and the two ends of the transverse holes 222 respectively penetrate the bottom surface of the annular groove 22 and the annular cavity 132 of the outer tube. When the two axial ends of the adapter block 2 are respectively connected to the corresponding three-layer tube ends, the positioning circular tubes 221 are respectively embedded in the stepped flange annular grooves 113 of the end faces of the stepped flanges 111 of the corresponding inner tube 11 ends, and the ends of the outer tube 13, the middle tube 12 and the inner tube 11 are respectively against the bottom surfaces of the corresponding annular recessed grooves 22, so that the two ends of the three-layer tube are respectively positioned in the corresponding vertical end faces of the adapter block 2. Since the two ends of the multiple transverse holes 222 are respectively connected to the outer tube annular cavity 132 of the three-layer tube, an outer nitrogen channel is provided for the three-layer tube, and the central hole 21 of the adapter block is connected to the inner tube 11, providing a central layer methanol fuel channel for the three-layer tube.

[0030] like Figure 3 and Figure 8 As shown, the limiting plate 3 is formed by butting two half limiting plates 31, and the adjacent sides of the half limiting plates 31 are respectively provided with semicircular notches 311 matching the circumference of the outer tube flange 131, and the semicircular notches 311 are radially provided with semicircular positioning grooves 312, and the outer tube flange 131 is respectively provided with radially extending positioning ring ribs 133. When the two half limiting plates 31 are positioned on the outer tube flange 131, the positioning ring ribs 133 are respectively embedded in the corresponding semicircular positioning grooves 312, and the semicircular notches 311 are against the outer circumference of the outer tube flange 131. The fastening screws 5 pass through the four corners of the limiting plate 3 spliced ​​by the two half limiting plates 31, and are screwed into the corresponding vertical end faces of the adapter block 2, so that multiple three-layer pipes are respectively connected through the adapter block 2 and the limiting plate 3 to form a pipe system with an integral structure.

[0031] The alcohol injector oil pipe joint 6 is fixed on the adapter block 2, the center hole 21 of the adapter block is connected to the inner tube 11 as the methanol fuel channel, and the adapter blocks 2 at both ends of the fuel supply pipe system connected to the alcohol injector oil pipe joint 6 are respectively connected to the methanol station and the nitrogen station through corresponding double-walled pipes. The alcohol injector oil pipe joint 6 leads to the alcohol injectors of each cylinder of the methanol fuel engine through the alcohol injector oil pipe, and the methanol fuel is respectively injected into each cylinder for combustion and work, ensuring the normal operation of the methanol fuel engine.

[0032] like Figure 2 , Figure 3 and Fig. 9 As shown, the power line 124 at the end of the arc-shaped PTC heating plate 14 passes through the left end of the middle tube annular cavity 132, and then is led to the outside of the outer tube 13 through the wiring tube 7; the inner end of the wiring tube 7 sequentially crosses the outer tube 13 and the middle tube 12, and is welded to the outer tube 13 respectively, the inside of the wiring tube 7 is sealed with a sealant 71, and the outer end of the wiring tube 7 is closed with a screw cover 72, and the power line 124 is led out from the center hole of the screw cover 72.

[0033] like Figure 3 As shown, two inner tube radial O-type sealing rings 114 are installed in the stepped flange annular groove 113 on the end face of the stepped flange 111, and an inner tube axial O-type sealing ring 115 is installed on the end face of the stepped flange 111, which effectively blocks the nitrogen in the middle tube annular cavity 132 from entering the inner tube 11. The outer tube end is equipped with an outer tube radial O-type sealing ring 134, which is used to seal the methanol fuel in the inner tube 11 to prevent it from leaking out, thereby ensuring the safety of the present invention.

[0034] In addition to the above embodiments, the present invention may also have other implementation modes. Any technical solutions formed by equivalent replacement or equivalent transformation shall fall within the protection scope required by the present invention.

Claims

1. A methanol fuel engine fuel supply pipe system with heating function, characterized in that: It comprises several three-layer tubes, adapter blocks respectively used to connect the three-layer tubes and limit plates respectively fixed at both ends of the adapter blocks, the three-layer tube comprises an inner tube, a middle tube, an outer tube and two arc-shaped PTC heating plates, the inner tube is a tube with stepped flanges at both ends and an annular groove recessed in the middle, the two arc-shaped PTC heating plates are respectively embedded in the annular grooves, and the radial end faces of the arc-shaped PTC heating plates are respectively limited by axial limit strips symmetrically arranged on the outer circumferential surface of the inner tube; the inner tube is inserted into the middle tube, the stepped flanges at both ends of the inner tube are threadedly connected to the two ends of the inner hole of the middle tube, and are coated with sealant, and a middle tube annular cavity with closed ends is provided between the outer circumferential surface of the arc-shaped PTC heating plate and the inner hole of the middle tube; two pairs of outwardly extending outer protrusions are arranged at intervals on the radial upper and lower sides of the outer circumferential surface of the middle tube, the middle tube is inserted into the outer tube, and through The O-ring sealing ring embedded in the top surface of the outer protrusion is sealed, and the ends of the outer tube are respectively provided with outer tube flanges; the connecting screws are respectively passed through the outer tube and screwed into the corresponding outer protrusions to fix the outer tube and the middle tube into one; an outer tube annular cavity serving as a nitrogen channel is provided between the inner hole of the outer tube and the outer circumference of the middle tube; the two ends of the three-layer tube are respectively inserted into one end of the corresponding adapter block, and the limit plates are respectively positioned on the ends of the outer tube and fixed on the corresponding vertical end faces of the adapter blocks, so that several three-layer tubes are respectively connected to form an integral structure of the pipe system through the adapter blocks and the limit plates; the oil pipe joints of the alcohol injector are respectively fixed on the adapter blocks, and the center holes of the adapter blocks are connected to the inner tube serving as the methanol fuel channel; the adapter blocks at both ends of the fuel supply pipe system are respectively connected to the methanol station and the nitrogen station through the corresponding double-walled pipes.

2. The fuel supply pipe system for a methanol fuel engine with a heating function as claimed in claim 1, characterized in that: The adapter block is a cube, and the centers of the vertical end faces at both ends of the adapter block are respectively provided with annular grooves with an inner diameter larger than the center hole of the adapter block, and the central axis of the annular grooves respectively extends outward with positioning circular tubes, and the inner diameter of the positioning circular tubes is larger than the aperture of the center hole of the adapter block; the centers of the two vertex angle inclined surfaces of the adapter block are respectively provided with threaded holes for the oil pipe joint of the alcohol injector and threaded holes for the pressure regulating valve, and the inner ends of the threaded holes for the oil pipe joint of the alcohol injector and the pressure regulating valve intersect perpendicularly with the center hole of the adapter block respectively; a plurality of transverse holes are distributed on the bottom surface of the annular groove, and the two ends of the transverse holes respectively penetrate the bottom surface of the annular groove and the annular cavity of the outer tube When the two axial ends of the adapter block are respectively connected to the corresponding three-layer tube ends, the positioning circular tubes are respectively embedded in the stepped flange annular grooves of the stepped flange end faces of the corresponding inner tube ends, and the ends of the outer tube, the middle tube and the inner tube are respectively abutted against the bottom faces of the corresponding annular grooves, so that the two ends of the three-layer tube are respectively positioned in the corresponding vertical end faces of the adapter block, and the two ends of the multiple transverse holes are respectively communicated with the annular cavity of the outer tube of the three-layer tube, and the center hole of the adapter block is communicated with the inner tube; the outer tube ends are respectively inserted into the annular grooves, and the limit plates are respectively fixed on the corresponding vertical end faces of the adapter blocks, so that the three-layer tube is fixedly connected into an integral structure through the adapter blocks.

3. The fuel supply pipe system for a methanol fuel engine with a heating function as claimed in claim 1, characterized in that: The limit plate is formed by connecting two half limit plates, and the adjacent sides of the half limit plates are respectively provided with semicircular notches matching the circumferential surface of the outer tube flange, the semicircular notches are radially provided with semicircular positioning grooves, and the outer tube flanges are respectively provided with radially extending positioning ring ribs; when the two half limit plates are positioned on the outer tube flange, the positioning ring ribs are respectively embedded in the corresponding semicircular positioning grooves, and the semicircular notches rest on the outer circumferential surface of the outer tube flange, and the fastening screws pass through the four corners of the limit plate spliced ​​by the two half limit plates, and are screwed into the corresponding vertical end faces of the adapter blocks, so that the two ends of the multiple three-layer tubes are fixedly connected to form an integral structure of the pipe system through the adapter blocks and the limit plates.

4. The fuel supply pipe system for a methanol fuel engine with a heating function as claimed in claim 1, characterized in that: The power line of the end of the arc-shaped PTC heating plate passes through one end of the annular cavity of the middle tube, and then is led to the outside of the outer tube through the wiring tube; the inner end of the wiring tube crosses the outer tube and the middle tube in turn, and is welded to the outer tube, the inside of the wiring tube is sealed with sealant, the outer end of the wiring tube is closed with a screw cover, and the power line is led out from the center hole of the screw cover.

5. The fuel supply pipe system for a methanol fuel engine with a heating function as claimed in claim 2, characterized in that: Two inner tube radial O-type sealing rings are installed in the annular groove of the stepped flange end face, and the positioning round tubes are respectively inserted into the annular grooves of the stepped flange end faces of the corresponding inner tube ends; the stepped flange end face is equipped with an inner tube axial O-type sealing ring, and the outer tube end is equipped with an outer tube radial O-type sealing ring.

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