A methanol direct injection injector

Abstract

The invention discloses a methanol direct injection injector, comprising: an injector body and a solenoid valve component, an orifice plate, a control valve seat and a needle valve component which are installed below the injector body through a tight cap of the injector body; wherein the solenoid valve component is located above the orifice plate, the orifice plate is located above the control valve seat, and the control valve seat is located above the needle valve component; a first and a second straight hole are arranged on the orifice plate, an inclined hole, a third straight hole and two small holes are arranged on the control valve seat, a needle valve component control chamber is arranged on the upper part of the needle valve component, the lower end of the first straight hole is communicated with the lower end of the second straight hole on the orifice plate and the upper ends of the inclined hole, the third straight hole and the two small holes on the control valve seat, and the lower ends of the inclined hole, the third straight hole and the two small holes on the control valve seat are communicated with the needle valve component control chamber; the opening and closing of the second straight hole on the orifice plate is controlled by turning on and off the power of the solenoid valve component, and then the methanol liquid pressure in the control chamber of the needle valve component is controlled to realize the start of the needle valve component injection.

Description

Technical Field

[0001] The invention relates to the technical field of fuel injectors, and in particular to a methanol direct injection injector. Background Art

[0002] The fuels used in existing internal combustion engines are generally traditional diesel, gasoline, natural gas, etc. In the face of the general trend of energy conservation and emission reduction, methanol, as a zero-carbon fuel, can reduce the generation of emission pollutants.

[0003] Methanol direct injection injectors are an important part of methanol engines. Existing methanol injectors are usually low-pressure methanol gas channel injection, using an electromagnetic injection valve structure with an injection pressure of 3-10 bar. Traditional diesel common rail injectors can achieve higher injection pressures, but cannot adapt to the flow characteristics of methanol media (poor lubricity), and the alcohol resistance of parts is extremely poor. Methanol high pressure causes serious cavitation in the flow channel. Methanol direct injection injectors require higher injection pressures (200-1200 bar) and good alcohol resistance. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a methanol direct injection injector for a methanol fuel injection system, in view of the fact that the above-mentioned existing methanol injectors are usually low-pressure methanol gas duct injection and cannot achieve the problem of methanol high-pressure direct injection. A high-pressure (200-1200bar) injector is provided, and at the same time, the problem of poor methanol lubrication and methanol cavitation is improved.

[0005] The technical problem to be solved by the present invention can be achieved by the following technical solutions:

[0006] A methanol direct injection injector, comprising:

[0007] An injector body, in which an oil inlet joint mounting hole, an oil storage cavity, a first oil outlet inclined hole and a second oil outlet inclined hole which are interconnected are sequentially arranged from top to bottom;

[0008] The electromagnetic valve component, orifice plate, control valve seat and needle valve component are installed under the injector body through the injector body cap; wherein the electromagnetic valve component is located above the orifice plate, the orifice plate is located above the control valve seat, and the control valve seat is located above the needle valve component; characterized in that,

[0009] An oil passage is arranged in the solenoid valve component, a first straight hole and a second straight hole are arranged on the orifice plate, an inclined hole, a third straight hole and two small holes are arranged on the control valve seat, and a needle valve component control chamber is arranged on the upper part of the needle valve component, the upper end of the first straight hole is communicated with the lower end of the oil passage, the lower end of the first straight hole is communicated with the lower end of the second straight hole on the orifice plate and the upper ends of the inclined hole, the third straight hole and the two small holes on the control valve seat, and the lower ends of the inclined hole, the third straight hole and the two small holes on the control valve seat are communicated with the needle valve component control chamber; the opening and closing of the second straight hole on the orifice plate is controlled by turning on and off the power of the solenoid valve component, and then the methanol liquid pressure in the needle valve component control chamber is controlled to realize the opening of the needle valve component for oil injection.

[0010] In a preferred embodiment of the present invention, the third straight hole consists of two sections, and the upper end has a smaller aperture; the two small holes each consist of two sections, and the lower end has a smaller aperture.

[0011] In a preferred embodiment of the present invention, an end face groove is provided on the contact surface between the orifice plate and the control valve seat, and the lower end of the first straight hole on the orifice plate is connected with the lower end of the second straight hole and the third straight hole and the upper ends of the two small holes in the control valve seat through the end face groove.

[0012] In a preferred embodiment of the present invention, the lower end diameters and lengths of the two small holes in the control valve seat are different.

[0013] In a preferred embodiment of the present invention, the orifice plate is made of martensitic stainless steel, and the upper portion of the orifice plate is plated using a plating process.

[0014] In a preferred embodiment of the present invention, a throttle plug is press-fitted into the oil inlet joint installation hole through the oil inlet joint, and the throttle plug has an inner hole; the oil inlet joint and the throttle plug are both made of martensitic stainless steel.

[0015] In a preferred embodiment of the present invention, the electromagnet component comprises an armature and an armature rod, and the armature and the armature rod are both made of martensitic stainless steel.

[0016] In a preferred embodiment of the present invention, the electromagnet component further includes a ball seat and a sealing ball for controlling the movement of the armature rod, the ball seat is made of martensitic stainless steel, and the sealing ball is a ceramic ball.

[0017] In a preferred embodiment of the present invention, the needle valve component is assembled from a needle valve body, a needle valve, a top sleeve, a spring, and an adjusting washer; the needle valve body, the needle valve, and the top sleeve are all made of martensitic stainless steel.

[0018] Due to the adoption of the above technical solution, the methanol direct injection injector of the present invention controls the opening and closing of the inner chamfer of the ceramic ball and the orifice plate through the electromagnetic force of the electromagnet to control the methanol liquid pressure in the control chamber of the needle valve component, so that the injection pressure of the methanol direct injection injector of the present invention can reach 200-1200bar, and at the same time, stainless steel materials and special heat treatment processes or coatings are used for each component to enable the injector to obtain excellent alcohol resistance. The clearance of each pair of the electromagnetic component and the needle valve component is adjusted to avoid various wear or jamming problems caused by poor lubricity of the methanol medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited to the scope of the embodiments.

[0020] Figure 1 It is a schematic structural diagram of the methanol direct injection injector of the present invention.

[0021] Figure 2 for Figure 1 An enlarged schematic diagram of point I.

[0022] Figure 3 It is a schematic diagram of the structure of the electromagnet component in the methanol direct injection injector of the present invention.

[0023] Figure 4 It is a schematic diagram of the structure of the needle valve component of the present invention. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0025] See also Figures 1 to 4 The methanol direct injection injector shown in the figure includes an injector body 100, a solenoid valve component 200, an orifice plate 300, a control valve seat 400 and a needle valve component 500.

[0026] The injector body 100 is made of martensitic stainless steel, and is provided with an oil inlet joint mounting hole 110, an oil storage chamber 120, an oil outlet inclined hole 130 (the aforementioned first oil outlet inclined hole) and an oil outlet inclined hole 140 (the aforementioned second oil outlet inclined hole) which are interconnected from top to bottom.

[0027] A small hole 150 is designed on the right side of the injector body 100. The small hole 150 is required for connecting the connector wire 210 used in the methanol direct injection injector to the solenoid valve component 200. A large inner hole 160 is designed on the upper part of the small hole 150 for press-fitting and fixing the connector wire 210; the lower part of the small hole 150 is designed with an enlarged inner hole 170 for connecting the connector 220 of the power magnet component 200. A flat square 180 is designed in the middle section of the injector body 100, which is mainly used for the installation and fixation of the methanol direct injection injector. A ring groove 190 and an external thread 190a are designed on the outer circle of the lower part of the injector body 100; the ring groove 190 is used to install the O-ring 190b to seal the methanol direct injection injector, and the external thread 190a is used to install the injector body tight cap 700.

[0028] The oil inlet joint 610 is installed in the oil inlet joint mounting hole 110 by threaded connection, and the oil inlet joint 610 presses the throttle plug 620 in the oil inlet joint mounting hole 110. The lower plane of the oil inlet joint 610 is in sealing contact with the upper plane of the throttle plug 620, and the spherical surface 621 at the bottom of the throttle plug 620 is in sealing contact with the spherical surface 111 between the oil inlet joint mounting hole 110 and the oil storage chamber 120, as follows:

[0029] The oil inlet connector 610 and the throttle plug 620 are both made of martensitic stainless steel, and inner holes 611 and 621 are provided in the oil inlet connector 610 and the throttle plug 620. Methanol will flow into the oil storage chamber 120 and the oil outlet inclined hole 130 of the injector body 100 through the inner hole 611 of the oil inlet connector 610 and the inner hole 621 of the throttle plug 620.

[0030] The upper outer circle of the oil inlet connector 610 is designed with an external thread 612 for connecting with the methanol oil inlet pipe through the thread; the upper end of the inner hole 611 is designed with a 60° inner chamfer 613 for sealing when the methanol oil inlet pipe is connected; a ring groove 614 is designed at the lower position of the external thread 611 for installing an O-ring 615; the lower end of the ring groove 613 is designed with an external hexagon 616 for installing the oil inlet connector 610 on the injector body 100 and connecting the oil inlet connector 610 with the methanol oil inlet pipe. An external thread 617 is also designed on the outer circle of the lower end of the oil inlet connector 610. The small outer circle 618 at the lower part of the external thread 616 is slightly smaller than the external thread 617. The external thread 617 is used to install the oil inlet connector 610 into the oil inlet connector mounting hole 110. The small outer circle 617 is mainly used to compress the throttle plug 620. A ring groove 618 is designed at the upper end of the external thread 617 for installing an O-ring 619 to achieve sealing between the oil inlet connector 610 and the oil inlet connector mounting hole 110.

[0031] The inner hole 621 of the throttling plug 620 is mainly composed of two sections of inner holes, the upper surface of the large inner hole 621a at the upper end is designed with an inner chamfer 621b to facilitate the circulation of methanol medium, and the small inner hole 621c at the lower end is smaller and is used for throttling.

[0032] The electromagnet component 200 is assembled from an electromagnet 230, an armature rod 240, an armature 250, an electromagnet valve seat 260, a gasket 270, a wave spring 280, a wave spring washer 290, a pressure regulating spring 290a, a pressure regulating spring washer 290c, a buffer spring 290d, a limit washer 290e, a ball seat 290f, and a ceramic ball 290g.

[0033] The basic structure of the electromagnet 230 is a hollow cylindrical shape with an inner hole 231. The outer surface of the electromagnet 230 is made of ferritic stainless steel, and the inside is wound into a coil with copper wire. Two coil connector pins 232 are set on the right side of the upper end of the electromagnet 230. The two coil connector pins 232 are cylindrical protrusions and are used to power the electromagnet 230.

[0034] The inner hole 231 of the electromagnet 230 is designed as a three-end inner hole, and the inner hole 231 becomes smaller from top to bottom. The two places at the upper end of the inner hole 231 are used to place the pressure regulating spring 290a and are enlarged to facilitate the smooth up and down movement of the armature rod 240; the lower end of the inner hole 231 cooperates with the armature rod 240. The end surface of the lower end of the electromagnet 230 is designed with a small boss 233, which is used to reduce the contact area between the armature 250 and the electromagnet 230 when the electromagnet 230 is working.

[0035] The armature rod 240 is made of martensitic stainless steel, and its basic structure is cylindrical. It is designed with three sections of cylinders. The upper cylinder is smaller and is used to adjust the installation of the spring washer 290c; the middle cylinder is the largest and is used to cooperate with the electromagnet 230 to ensure that the armature rod 240 can move smoothly in the inner hole 231 of the electromagnet 230; the lower cylinder is smaller and has an interference fit with the inner hole 251 of the armature 250, and the armature rod 240 is driven by the armature 250 to move.

[0036] The armature 250 is made of martensitic stainless steel, and its basic structure is a hollow cylinder with an inner hole 251. The outer circumference of the armature 250 has two upper and lower outer circles 252 and 253. The upper outer circle 252 is a large outer circle, and the lower part of the large outer circle is designed as an inclined surface 254, which is used to enhance the electromagnetic force on the armature 250. Three through grooves 252a are designed on the outer circle 252 for the circulation of methanol medium when the armature 250 moves upward under the electromagnetic force; the lower outer circle 253 is smaller and is used for the installation of the buffer spring 290d.

[0037] The ball seat 290f is made of martensitic stainless steel and has a cylindrical basic structure. The lower end is designed with a concave spherical surface 291f for fixing the ceramic ball 290g.

[0038] The ceramic ball 290 g is made of ceramic and has a basic structure of a sphere, and is mainly used to seal with the inner chamfer 330 on the orifice plate 300 .

[0039] The solenoid valve seat 260 is made of martensitic stainless steel and has a solenoid mounting hole 261 for mounting the solenoid 230, an armature mounting hole 262, a transition cone hole 263, a limit washer mounting hole 264, an armature rod passing hole 265, an oil passage hole 266, an oil passage hole 267 and an oil return hole (not shown in the figure). The oil passage hole 266 and the oil passage hole 267 constitute the oil passage in the aforementioned solenoid valve component.

[0040] The electromagnet mounting hole 261, the armature mounting hole 262, the transition cone hole 263, the limit washer mounting hole 264, and the armature rod through hole 265 are coaxial and connected in sequence. The diameter of the electromagnet mounting hole 261 is larger than the diameter of the armature mounting hole 262, the diameter of the armature mounting hole 262 is larger than the diameter of the limit washer mounting hole 264, and the diameter of the limit washer mounting hole 264 is larger than the armature rod through hole 265. The large end of the transition cone hole 263 is connected to the lower end of the armature mounting hole 262, and the small end of the transition cone hole 263 is connected to the limit washer mounting hole 264. The lower end of the oil channel hole 266 is connected to the lower end of the oil channel hole 267. The oil return hole is connected to the lower end of the armature rod through hole 265.

[0041] During installation, firstly, the ball seat 290e and the ceramic ball 290f are installed from top to bottom in the armature rod through hole 265 of the electromagnetic valve seat 260; then the electromagnet 230, the armature rod 240, and the armature 250 are assembled into a solenoid valve assembly; then, the limit washer 290e is installed in the limit washer mounting hole 264, and the buffer spring 290d is installed in the transition cone hole 263 and the armature mounting hole 262 and pressed on the limit washer 290e; then the electromagnetic valve assembly is installed in the electromagnetic mounting hole 261 and the lower end of the armature rod 240 is inserted into the armature rod through hole 265 and pressed on the ball seat 290e, and the armature 250 is inserted into the armature mounting hole 262 to press the buffer spring 290d; the buffer spring 290d is sleeved on the outer circle of the lower section of the armature 250 253; then install the pressure-adjusting spring washer 290c and the pressure-adjusting spring 290a into the inner hole 251 of the armature 250 and sleeve on the upper end of the armature rod 240; then install the backing plate 270, the wave spring 280, and the wave spring washer 290 on the top of the electromagnet 230 from top to bottom, and the two coil connector pins 232 on the electromagnet 230 pass through the wave spring washer 290, the wave spring 280 and the backing plate 270 from bottom to top and are inserted into the inner hole 170 of the injector body 100, and are connected to the lower end of the connector 220 of the electromagnet component 200, the backing plate 270 presses the wave spring 280 on the wave spring washer 290, and the upper end of the pressure-adjusting spring 290a passes through the wave spring washer 290 and the wave spring 280 to act on the backing plate 270.

[0042] The orifice plate 300 is made of martensitic stainless steel, and its basic structure is cylindrical. A straight hole 310 (the aforementioned first straight hole) is designed on the left side for the flow of methanol medium. An end face groove 320 is designed at the lower end of the straight hole 310 for the flow of methanol medium to the straight hole 410 on the left side of the control valve seat 400. A straight hole 320 (the aforementioned second straight hole) is also designed on the right side. An inner chamfer 330 is designed at the upper end of the straight hole 320 for sealing with the ceramic ball 290g, and an end face groove 340 is designed at the lower end for communicating with two small holes 420 and 430 on the right side of the control valve seat 400. The end face groove 320 is connected with the end face groove 340 to form an end face groove. The upper part of the orifice plate 300 is plated by a coating process to increase the alcohol resistance and wear resistance of the contact cone surface of the inner chamfer 330.

[0043] The control valve seat 400 is made of martensitic stainless steel, and its basic structure is cylindrical. An inclined hole 440 is designed on the left side for the flow of methanol medium. On the right side of the inclined hole 440, a straight hole 410 (the aforementioned third straight hole) and small holes 420 and 430 are designed from right to left. The straight hole 410 consists of two sections, and the upper end has a smaller aperture. The small holes 420 and 430 both consist of two sections, and the lower end has a smaller aperture. The lower end apertures of the small holes 420 and 430 are different in length, so that the throttling effects of the small holes 420 and 430 are different.

[0044] The needle valve component 500 is assembled from a needle valve body 510 , a needle valve 520 , a top sleeve 530 , a spring 540 , and an adjusting washer 550 .

[0045] The needle valve body 510 is made of martensitic stainless steel and adopts nitriding heat treatment process to improve wear resistance and resistance to high-pressure methanol cavitation. The basic structure of the needle valve body 510 is a hollow cylinder, and its outer circle is designed with four sections of cylinders 511, 512, 513, and 514. The cylinder 511 has a smaller diameter than the cylinder 512, and is mainly used to reduce the bottom contact area with the control valve seat 400 to improve the sealing quality; the cylinder 512 is mainly used for tightening the injector body cap 700 during installation; the cylinder 513 is mainly used for cooperating with the injector body cap 700 for installation; the lower end of the cylinder 514 is designed with a slope 515, and the head of the slope 515 is a protruding spherical surface 516, and the protruding spherical surface 516 is designed with small holes 517 distributed circumferentially, and the small holes 517 are used for methanol injection.

[0046] The interior of the needle valve body 510 is mainly composed of three sections of inner holes 510a, 510b, and 510c. The upper end of the inner hole 510a is designed with an inclined surface and a circular arc transition surface 510d to facilitate the circulation of methanol medium; the intersection of the inner hole 510b and the inner hole 510a is designed with an arc transition. The inner hole 510b is mainly used to cooperate with the needle valve 520. The middle and lower parts of the inner hole 510b are designed with circular grooves to reduce the contact area between the needle valve 520 and the needle valve body 510; the lower end of the inner hole 510c is designed with an inner conical surface 510e, and the inner conical surface 510e is used to seal with the conical surface 521 of the needle valve 520.

[0047] The needle valve 520 is made of martensitic stainless steel, and its basic structure is cylindrical. From top to bottom, there are five sections of cylinders 521, 522, 523, 524, and 525. The upper end of the cylinder 521 is designed with an inclined surface and an arc angle, which is mainly convenient for installing and assembling the top sleeve 530; the upper end surface of the cylinder 522 is used to adjust the installation of the gasket 550; the cylinder 523 is used to cooperate with the inner hole 510b of the needle valve body 510, and at the same time, it meets the flexible movement of the needle valve 520 in the needle valve body 510. The cylinder 524 is designed with flat squares, which are evenly distributed on three sides and are mainly used for methanol to flow to the head of the needle valve body 510; the lower end of the cylinder 525 is designed with a conical surface 521, which cooperates with the inner conical surface 510e of the needle valve body 510 to form a seal; the needle valve 520 adopts a coating to increase the alcohol resistance and wear resistance.

[0048] The top sleeve 530 is made of martensitic stainless steel, and its basic structure is a hollow cylinder. The outer circle of the upper end of the cylinder is designed with a chamfer, which is mainly used to reduce the contact area between the upper end face of the top sleeve 530 and the lower end face of the control valve seat 400, and to improve the sealing performance of the top sleeve 530 and the lower end face of the control valve seat 400; the inner hole of the top sleeve 530 is installed on the cylinder 522 of the needle valve 520 and cooperates with the needle valve 520; the spring 540 and the adjusting washer 550 are sleeved on the cylinder 521 through the top sleeve 530, the lower end face of the adjusting washer 550 contacts the upper end face of the cylinder 522, the lower end of the spring 540 acts on the upper end face of the adjusting washer 550, and the upper end of the spring 540 acts on the lower end face of the top sleeve 530.

[0049] The methanol liquid chamber formed by the inner holes 510a, 510b, the cylinders 521, 522 of the needle valve 520, the top sleeve 530 and the control valve seat 400 is defined as the needle valve component control chamber 560; the operation of the methanol direct injection injector is controlled by controlling the change of methanol pressure through the needle valve component control chamber 560.

[0050] During installation, the injector body cap 700 sequentially installs the needle valve component 500, the control valve seat 400 and the orifice plate 300 on the lower end of the injector body 100 from bottom to top, the internal thread 710 on the upper end of the injector body cap 700 is aligned with the external thread 190a of the injector body 100, the upper end of the straight hole 310 on the orifice plate 300 is aligned with the lower end of the oil outlet inclined hole 140 in the injector body 100 and connected, and the ceramic ball 290g is pressed into the inner chamfer 330 of the orifice plate 300; the upper end of the inclined hole 440 of the control valve seat 400 is aligned with the upper end of the straight hole 310 on the orifice plate 300 and connected with the lower end of the oil outlet inclined hole 140 in the injector body 100. The lower end of the inclined hole 440 of the control valve seat 400 is aligned with and connected to the straight hole 310 on the orifice plate 300 and is connected to the inner hole 510a of the needle valve body 510; the upper end of the straight hole 410 of the control valve seat 400 is connected to the end surface groove 320 on the orifice plate 300, and the lower end of the straight hole 410 is connected to the inner hole 510a of the needle valve body 510; the upper ends of the small holes 420 and 430 of the control valve seat 400 are connected to the end ring groove 340 of the orifice plate 300, and the lower ends of the small holes 420 and 430 are connected to the inner hole 510a of the needle valve body 510. By designing the minimum aperture of the straight hole 410 and the small holes 420 and 430, the control valve seat 400 can realize that when the ceramic ball 290g is opened, the liquid pressure in the needle valve component control chamber 560 decreases.

[0051] The methanol enters the oil storage chamber 120 through the oil inlet joint 610 and the inner hole 621 of the throttle plug 620, flows into the straight hole 310 of the orifice plate 300 through the oil outlet inclined hole 130, the oil outlet inclined hole 140 in the injector body 100, the oil channel hole 266, and the oil channel hole 267 in the solenoid valve seat 260, and then enters the straight hole 410, the small holes 420, 430 and the straight hole 320 in the control valve seat 400 through the end surface groove 320 and the end surface groove 340 on the orifice plate 300, and then flows into the needle valve component control chamber 560 through the inclined hole 440, the straight hole 410 and the small holes 420, 430 in the control valve seat 400 to fill the entire needle valve component 500.

[0052] The working principle of the methanol direct injection injector of the present invention is:

[0053] When the connector wire 210 is energized, the electromagnet 230 generates an electromagnetic force, which acts on the armature 250, causing the armature 250 to move upward. The armature 250 drives the armature rod 240 to move upward by overcoming the spring force of the pressure-adjusting spring 290a. The ball seat 290f and the ceramic ball 290g lose the pressure of the armature rod 240. Under the pressure of the methanol liquid, the sealing contact surface between the ceramic ball 290g and the inner chamfer 330 of the orifice plate 300 is opened, and part of the methanol flows back from the gap between the ceramic ball 290g and the inner chamfer 330 of the orifice plate 300 to the armature rod through hole 265, and then flows back to the oil return hole through the armature rod through hole 265 and the three through grooves 252a of the armature 250.

[0054] After the sealing contact surface between the ceramic ball 290g and the inner chamfer 330 of the orifice plate 300 is opened, the straight hole 410 and the small holes 420 and 430 on the control valve seat 400 have different apertures, and the outflow rate of methanol in the needle valve component control cavity 560 through the orifice plate 300 is greater than the inflow rate of methanol, causing the pressure in the needle valve component control cavity 560 to drop. The needle valve 520 is subjected to a methanol liquid pressure greater than the spring force of the spring 540, and the needle valve 520 moves upward, so that the sealing position between the conical surface 521 of the needle valve 520 and the inner conical surface 510e of the needle valve body 510 is opened, and methanol is ejected through the small hole 510f at the front end of the needle valve body 510;

[0055] When the electromagnet 230 is powered off, the armature 250 is no longer subjected to the electromagnetic force, and the armature rod 240 is pressed downward by the spring force of the pressure regulating spring 290a, so that the ball seat 290f and the ceramic ball 290g move downward, and the sealing contact surface of the ceramic ball 290g and the inner chamfer 330 of the orifice plate 300 are resealed. After the sealing contact surface of the ceramic ball 290g and the inner chamfer 330 of the orifice plate 300 are resealed, the methanol pressure in the needle valve component control chamber 560 rises, so that the needle valve 520 loses the force generated by the liquid pressure difference. Under the pressure of the spring 540, the needle valve 520 reseals the conical surface 521 of the needle valve 520 with the inner conical surface 510e of the needle valve body 510, and the injection ends;

[0056] The methanol direct injection injector of the present invention controls the opening and closing of the ceramic ball 290g and the inner chamfer 330 of the orifice plate 300 by the electromagnetic force of the electromagnet 230 to control the methanol liquid pressure in the needle valve component control chamber 560, so that the injection pressure of the methanol direct injection injector of the present invention can reach 200-1200bar. At the same time, stainless steel materials and special heat treatment processes or coatings are used for various parts to enable the injector to obtain excellent alcohol resistance. The matching clearance of each pair of the electromagnetic component 200 and the needle valve component 500 is adjusted to avoid various wear or jamming problems caused by poor lubricity of the methanol medium.

Claims

1. A methanol direct injection injector, comprising: An injector body, in which an oil inlet joint mounting hole, an oil storage cavity, a first oil outlet inclined hole and a second oil outlet inclined hole which are interconnected are sequentially arranged from top to bottom; The electromagnetic valve component, orifice plate, control valve seat and needle valve component are installed under the injector body through the injector body cap; wherein the electromagnetic valve component is located above the orifice plate, the orifice plate is located above the control valve seat, and the control valve seat is located above the needle valve component; characterized in that, An oil passage is arranged in the solenoid valve component, a first straight hole and a second straight hole are arranged on the orifice plate, an inclined hole, a third straight hole and two small holes are arranged on the control valve seat, and a needle valve component control chamber is arranged on the upper part of the needle valve component, the upper end of the first straight hole is communicated with the lower end of the oil passage, the lower end of the first straight hole is communicated with the lower end of the second straight hole on the orifice plate and the upper ends of the inclined hole, the third straight hole and the two small holes on the control valve seat, and the lower ends of the inclined hole, the third straight hole and the two small holes on the control valve seat are communicated with the needle valve component control chamber; the opening and closing of the second straight hole on the orifice plate is controlled by turning on and off the power of the solenoid valve component, and then the methanol liquid pressure in the needle valve component control chamber is controlled to realize the opening of the needle valve component for oil injection.

2. A methanol direct injection injector according to claim 1, characterized in that: The third straight hole is composed of two sections, and the aperture of the upper end is smaller; the two small holes are composed of two sections, and the aperture of the lower end is smaller.

3. A methanol direct injection injector according to claim 2, characterized in that: An end face groove is provided on the contact surface between the orifice plate and the control valve seat, and the lower end of the first straight hole on the orifice plate is connected with the lower end of the second straight hole and the third straight hole and the upper ends of the two small holes in the control valve seat through the end face groove.

4. A methanol direct injection injector according to claim 3, characterized in that: The lower end diameters and lengths of the two small holes in the control valve seat are different.

5. A methanol direct injection injector according to claim 4, characterized in that: The orifice plate is made of martensitic stainless steel, and the upper portion of the orifice plate is plated using a plating process.

6. A methanol direct injection injector according to claim 5, characterized in that: A throttle plug is press-fitted in the oil inlet joint installation hole through the oil inlet joint, and the throttle plug has an inner hole; the oil inlet joint and the throttle plug are both made of martensitic stainless steel.

7. A methanol direct injection injector according to claim 6, characterized in that: The electromagnet component comprises an armature and an armature rod, and the armature and the armature rod are both made of martensitic stainless steel.

8. A methanol direct injection injector according to claim 7, characterized in that: The electromagnet component also includes a ball seat and a sealing ball for controlling the movement of the armature rod. The ball seat is made of martensitic stainless steel, and the sealing ball is a ceramic ball.

9. A methanol direct injection injector according to claim 8, characterized in that: The needle valve component is assembled from a needle valve body, a needle valve, a top sleeve, a spring, and an adjusting washer; the needle valve body, the needle valve, and the top sleeve are all made of martensitic stainless steel.

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