A high-pressure airflow-assisted water jet nozzle and grinding method

Abstract

The present invention belongs to the technical field of rail grinding, and specifically discloses a high-pressure airflow-assisted water jet nozzle and a grinding method. It includes: a nozzle structure body; a high-pressure water flow inlet, arranged along the axial direction of the nozzle structure body; a solid abrasive channel, arranged on the side wall of the nozzle structure body; a solid-liquid two-phase mixing chamber, arranged in the nozzle structure body, and the solid-liquid two-phase mixing chamber is connected with the high-pressure water flow inlet and the solid abrasive channel; a sand pipe, arranged in the lower part of the nozzle structure body, and the sand pipe is connected with the solid-liquid two-phase mixing chamber; a high-pressure airflow module, including an air pipe channel, an annular air pipe and a gas injection section that are connected in sequence, and the gas injection section is used to adjust the focusing angle of the airflow according to the grinding distance, so that the abrasive sprayed by the sand pipe corrects the jet direction under the action of airflow constraint. The present invention can increase the effective spraying distance of the abrasive water jet, focus the spraying energy, and effectively prevent the nozzle from being too close to the object and causing breakage.

Description

Technical Field

[0001] The present invention belongs to the technical field of rail grinding, and more specifically, relates to a high-pressure airflow-assisted water jet nozzle and a grinding method. Background Art

[0002] Due to the unique cold processing characteristics of abrasive waterjet, it has become the fastest-growing special processing technology in the past forty years. Its application is becoming more and more common. It is currently widely used in aerospace, mechanical processing, automobile manufacturing, foundry, weapons industry, electronics, construction and papermaking industries. The water jet nozzle is the main component in the jet processing process. Its quality and rationality of structure determine the processing quality of the jet, so the influence on it is of great significance.

[0003] At present, the target distance of traditional water jet nozzles used in cutting, grinding and other application scenarios needs to be controlled at 3-6mm. The effective jet target distance is short and is more suitable for situations where the workpiece on the machine tool is stationary. However, in some actual uses, such as grinding rails during movement, the target distance needs to be greater than 10mm, and at the same time, the nozzle sand tube must be prevented from being damaged due to vibration and collision with the workpiece surface.

[0004] There are some public patents that optimize the nozzle structure by introducing self-oscillating jets, cavitation jets, rotating jets, pulse jets and other methods. For example, the invention patent CN108855662A discloses a multi-hole straight-rotating mixed cavitation jet nozzle. The presence of axial through holes on the guide member and the rotating body, the presence of a rotating impeller and the presence of a contracting and expanding horizontal forward jet port combine continuous straight jets, rotating jets and cavitation jets, which can effectively improve the water jet processing quality with low cost. However, the effective processing target distance has not been increased. At the same time, there is currently no related invention that can effectively increase the processing target distance.

[0005] Based on the above defects and shortcomings, the art urgently needs to propose a high-pressure airflow assisted water jet nozzle structure and a control method thereof, which can effectively improve the processing target distance. Summary of the invention

[0006] In view of the above defects or improvement needs of the prior art, the present invention provides a high-pressure airflow assisted water jet nozzle and a grinding method, wherein a high-pressure airflow assisted water jet nozzle is designed accordingly in combination with the characteristics of the water jet nozzle itself and the characteristics of the rail grinding process, and its key components such as the structure of the nozzle body, the high-pressure water flow inlet, the solid abrasive channel, the solid-liquid two-phase mixing chamber, the sand pipe and the high-pressure airflow module and their specific settings are studied and designed, which can increase the effective spraying distance of the abrasive water jet, focus the spraying energy, and effectively prevent the nozzle from being too close to the object and causing breakage.

[0007] To achieve the above object, according to one aspect of the present invention, a high-pressure airflow assisted water jet nozzle is provided, comprising:

[0008] Nozzle structure body;

[0009] A high-pressure water inlet is provided at an upper portion of the nozzle structure body and is arranged axially along the nozzle structure body;

[0010] A solid abrasive channel is provided on the side wall of the nozzle structure body;

[0011] A solid-liquid two-phase mixing chamber is provided in the nozzle structure body, and the solid-liquid two-phase mixing chamber is communicated with the high-pressure water inlet and the solid abrasive channel;

[0012] A sand pipe is arranged at the lower part of the nozzle structure body and is connected with the solid-liquid two-phase mixing chamber;

[0013] The high-pressure airflow module comprises an air pipe channel, an annular air pipe and a gas injection section which are connected in sequence. The air pipe channel is used to input an airflow of specified air pressure to the gas injection section. The gas injection section is used to adjust the focusing angle of the airflow according to the grinding distance, so that the abrasive sprayed by the sand tube can correct the jet direction under the action of the airflow constraint.

[0014] As a further preference, a gas convergence tube is further provided between the annular air tube and the gas injection section, the gas convergence tube is a conical structure, and the annular cross-section of the annular air tube is larger than the annular cross-section of the gas injection section.

[0015] As a further preferred embodiment, it further comprises a field generator, which is arranged in the gas injection section and is used to generate a continuously adjustable magnetic field;

[0016] The gas injection section includes a magnetic fluid deformable wall, the magnetic fluid deformable wall is provided with a magnetic fluid cavity, the magnetic fluid cavity can be deformed, a magnetic fluid is provided in the magnetic fluid cavity, the hardness of the magnetic fluid can change with the change of the magnetic field strength of the magnetic field generated by the field generator, thereby changing the axial inner wall slope of the magnetic fluid deformable wall.

[0017] As a further preferred embodiment, the hardening ability of the magnetic fluid is positively correlated with the magnetic induction intensity of the magnetic field generated by the field generator, and the function of the hardening ability of the magnetic fluid and the magnetic field induction intensity is η=k(μ-1)H 2 , where η is the magnetic viscosity, the greater the magnetic viscosity, the greater the hardness, k is the proportional coefficient, μ is the magnetic permeability of the magnetic fluid, and H is the magnetic field strength.

[0018] As further preferred, the field generator includes an electromagnetic coil, which is arranged in the magnetic fluid cavity, and the electromagnetic coil can generate a continuously adjustable magnetic field according to the current density flowing inside, and the function of the magnetic induction intensity of the magnetic field excited by the electromagnetic coil and the current density flowing in the electromagnetic coil is: Wherein, S is an arbitrary closed curve in space, J is the current density in the energized coil, and L is the boundary of the closed curve.

[0019] As a further preferred embodiment, the current density flowing through the electromagnetic coil is positively correlated with the current flowing through the electromagnetic coil, and the function is: I is the current flowing through the electromagnetic coil, π is the pi, and r is the radius of the electromagnetic coil.

[0020] As further preferred, there are multiple electromagnetic coils, and the multiple electromagnetic coils are arranged in the gas injection section. Currents of different magnitudes can flow through each of the electromagnetic coils to form the magnetic fluid with continuous different hardness in the gas injection section.

[0021] According to another aspect of the present invention, there is also provided a rail water jet continuous adjustable grinding method, which is implemented by using the nozzle, and comprises:

[0022] S1 starts the grinding vehicle, collects rail surface images through industrial cameras, and sends the rail surface images to the grinding vehicle control center through a signal transmitter;

[0023] The S2 grinding vehicle control center performs defect feature recognition on the received rail surface image through an image processing algorithm to obtain a rail defect feature data signal;

[0024] The S3 grinding vehicle control center marks the location of the rail disease and determines the rail damage according to the characteristic data signal of the rail disease, and identifies the driving parameters and grinding positioning parameters of the grinding vehicle at the same time;

[0025] The S4 grinding vehicle control center controls the automatic opening and closing of the nozzle of each water jet grinding device after reaching the location of the defect according to the location of the rail defect, the driving parameters of the grinding vehicle and the grinding positioning parameters. At the same time, when the nozzle is working, the grinding vehicle control center controls the field generator on the nozzle to generate a continuously adjustable solidified magnetic field according to the rail damage situation, and then changes the focusing angle of the nozzle airflow to adapt to the working mode compatible with the rail damage, thereby achieving all targeted grinding and repair tasks of the rail damage at the location of the defect.

[0026] A rail water jet continuously adjustable grinding method, characterized in that the grinding vehicle driving parameter in step S3 includes the grinding vehicle driving speed;

[0027] The grinding positioning parameters include the distance between the industrial camera and the center position of the first row of row cutters of the frontmost water jet grinding device and the distance between two adjacent row cutters of the water jet grinding device.

[0028] As a further preferred embodiment, the completion of all the grinding and repairing tasks at the location of the defect in step S4 further includes the following steps:

[0029] The S41 grinding vehicle control center calculates the time required for the first drainage knife of the water jet grinding device to reach the location of the defect according to the driving speed of the grinding vehicle and the distance between the industrial camera and the center position of the first drainage knife of the front water jet grinding device, and controls the first drainage knife to automatically open and close the nozzle to complete the grinding task after reaching the location of the defect;

[0030] S42 The grinding vehicle control center calculates the time required for the second drainage knife to reach the defect after the first drainage knife completes the grinding task according to the driving speed of the grinding vehicle and the distance between two adjacent drainage knives, and controls the second drainage knife to automatically open and close the nozzle to complete the grinding task after reaching the location of the defect;

[0031] S43 and so on, the grinding control module of the grinding vehicle control center calculates the time required for each subsequent drainage knife to reach the defect in turn, and controls each subsequent drainage knife to automatically open and close the nozzle after reaching the location of the defect to complete the grinding task until all grinding and repair tasks at the location of the defect are completed.

[0032] In general, the above technical solution conceived by the present invention has the following technical advantages compared with the prior art:

[0033] 1. The nozzle structure of the present invention can increase the effective spraying distance of the abrasive water jet, focus the spraying energy, and effectively prevent the nozzle from being too close to the object and causing breakage by introducing 6-15 bar bypass high-pressure gas and modifying the outlet structure of the abrasive water jet nozzle.

[0034] 2. In the present invention, when the distance between the object and the nozzle is small, the bypass high-pressure gas does not work; when the target distance continues to increase, an air compressor or a portable high-pressure gas cylinder can be connected to adjust the output pressure to achieve the effect of focusing the abrasive water jet column, thereby increasing the effective jet target distance.

[0035] 3. The present invention introduces bypass high-pressure gas to blow residual sewage and fine cutting waste away from the workpiece, thereby achieving air drying of the workpiece surface after the action and preventing rust-prone workpieces from rusting. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic structural diagram of a high-pressure airflow-assisted water jet nozzle involved in an embodiment of the present invention;

[0037] Figure 2 yes Figure 1 A partial enlarged view of the gas convergence tube and the gas injection section;

[0038] Figure 3 is a schematic diagram of the three-dimensional structure of a high-pressure airflow-assisted water jet nozzle involved in an embodiment of the present invention;

[0039] Figure 4 It is a structural schematic diagram of a gas injection section in a high-pressure airflow-assisted water jet nozzle involved in an embodiment of the present invention.

[0040] In all the drawings, the same reference numerals represent the same technical features, specifically: 1-high-pressure water inlet, 2-gem nozzle, 3-solid-liquid two-phase mixing chamber, 4-convergence tube, 5-solid abrasive channel, 6-bypass high-pressure gas inlet, 7-air pipe channel, 8-sand tube, 9-annular air tube, 10-gas convergence outlet, 8-sand tube, 9-annular air tube, 101-gas convergence tube, 102-gas injection section, 1021-magnetic fluid, 1022-electromagnetic coil. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0042] like Figures 1 to 4 As shown, a high-pressure airflow assisted water jet nozzle provided in an embodiment of the present invention includes: a nozzle structure body; a high-pressure water flow inlet 1, which is arranged at the upper part of the nozzle structure body and arranged axially along the nozzle structure body; a solid abrasive channel 5, which is arranged on the side wall of the nozzle structure body; a solid-liquid two-phase mixing chamber 3, which is arranged in the nozzle structure body, and the solid-liquid two-phase mixing chamber 3 is connected to the high-pressure water flow inlet 1 and the solid abrasive channel 5; a sand pipe 8, which is arranged at the lower part of the nozzle structure body, and the sand pipe 8 is connected to the solid-liquid two-phase mixing chamber 3; a high-pressure airflow module, including an air pipe channel 7, an annular air pipe 9 and a gas injection section 102 connected in sequence, the air pipe channel 7 is used to input an airflow of a specified air pressure to the gas injection section 102, and the gas injection section 102 is used to adjust the focusing angle of the airflow according to the grinding distance, so that the abrasive sprayed by the sand pipe 8 corrects the jet direction under the action of airflow constraint.

[0043] A gas convergence pipe 101 is further provided between the annular air pipe 9 and the gas injection section 102 . The gas convergence pipe 101 is a conical structure. The annular cross section of the annular air pipe 9 is larger than the annular cross section of the gas injection section 102 .

[0044] More specifically, in one embodiment of the present invention, the gas injection section 102 adjusts the airflow focus point by adjusting the inner wall thickness thereof, so that the abrasive injected by the sand tube 8 corrects the jet direction under the airflow constraint. For example, in one embodiment, the nozzle further includes a field generator, which is arranged in the gas injection section 102 and is used to generate a continuously adjustable magnetic field; the gas injection section 102 includes a magnetic fluid deformation wall, the magnetic fluid deformation wall is provided with a magnetic fluid cavity, the magnetic fluid cavity can be deformed, a magnetic fluid is arranged in the magnetic fluid cavity, and the hardness of the magnetic fluid can change with the change of the magnetic field strength of the magnetic field generated by the field generator, thereby changing the axial inner wall slope of the magnetic fluid deformation wall.

[0045] In the above embodiment, the hardening ability of the magnetic fluid is positively correlated with the magnetic induction intensity of the magnetic field generated by the field generator, and the function of the hardening ability of the magnetic fluid and the magnetic field induction intensity is η=k(μ-1)H 2 , where η is the magnetic viscosity. The greater the magnetic viscosity, the greater the hardness. k is the proportionality coefficient. μ is the magnetic permeability of the magnetic fluid. H is the magnetic field strength. The field generator includes an electromagnetic coil, which is arranged in the magnetic fluid cavity. The electromagnetic coil can generate a continuously adjustable magnetic field according to the current density flowing inside. The function of the magnetic induction intensity of the magnetic field excited by the electromagnetic coil and the current density flowing in the electromagnetic coil is: Where S is an arbitrary closed curve in space, J is the current density in the energized coil, and L is the boundary of the closed curve. The current density flowing through the electromagnetic coil is positively correlated with the current flowing through the electromagnetic coil, and its function is I is the current flowing through the electromagnetic coil, π is the pi, and r is the radius of the electromagnetic coil.

[0046] In one embodiment of the present invention, a plurality of electromagnetic coils are provided in the gas injection section 102 , and currents of different magnitudes can flow through each electromagnetic coil to form the magnetic fluid with continuous different hardnesses in the gas injection section 102 .

[0047] In one embodiment of the present invention, the nozzle includes a high-pressure water inlet 1, a jewel nozzle 2, a solid-liquid two-phase mixing chamber 3, a convergent tube 4, a solid abrasive channel 5, and a sand tube 8; the bypass high-pressure auxiliary gas system includes a bypass high-pressure gas inlet 6, an air pipe channel 7, an annular hollow air pipe 9, and a gas convergent outlet 10. The jewel nozzle 2 is arranged below the high-pressure water inlet 1, one end of the solid abrasive channel 5 is connected to the solid-liquid two-phase mixing chamber 3 from the side, the end of the solid-liquid two-phase mixing chamber 3 is connected to the convergent tube 4, and the top of the sand tube 8 is connected to the convergent tube 4. After the high-pressure water flows through the jewel nozzle 2, it enters the mixing chamber 3 at high speed, and the high-speed fluid entrains the solid abrasive in the solid abrasive channel 5, which is fully mixed in the solid-liquid two-phase mixing chamber 3, and the solid-liquid two-phase flow is accelerated through the convergent tube 4 and the sand tube 8 and then ejected. The bypass high-pressure gas inlet 6 is provided with bolt holes and threads, and can be externally connected to a compressed air machine or a portable high-pressure gas cylinder when in use. The end of the bypass high-pressure gas inlet 6 is connected to the air pipe channel 7, and the air pipe channel 7 is connected to the annular hollow air pipe 9, and the end of the annular hollow air pipe 9 is connected to the gas convergence outlet 10. When the target distance is far, the solid-liquid two-phase flow is ejected from the sand pipe 8, but in the development stage of the ejection, the jet column will continue to spread around, so a cylindrical hollow high-pressure gas wall is added around it to focus the energy of the solid-liquid two-phase flow.

[0048] The nozzle of the present invention is installed on a rail water jet grinding system based on visual positioning, which includes a grinding vehicle driving guidance module, a grinding vehicle power module, a water jet grinding module and an intelligent positioning module arranged on the water jet grinding vehicle; the grinding vehicle driving guidance module includes a grinding vehicle control center, a driver's seat and an electric control cabinet in the cab; the grinding vehicle control center includes a signal receiving module, an image processing algorithm module, a rail disease marking module, a parameter setting and identification module and a grinding control module; the signal receiving module is used to receive the rail surface image data collected and sent by the intelligent positioning module; the image processing algorithm module is used to perform disease feature recognition on the rail surface image data received by the signal receiving module and obtain a rail disease feature data signal; the rail disease marking module is used to mark the location of the rail disease; the parameter setting and identification module is used to set and identify the grinding vehicle driving parameters and grinding positioning parameters; The grinding control module is used to control the water jet grinding module to perform grinding tasks, including controlling the automatic opening and closing of the grinding water jet and controlling the nozzle to adjust to different calibers; the driving parameters of the grinding vehicle include the driving speed of the grinding vehicle; the grinding positioning parameters include the distance between the industrial camera and the center position of the first drainage knife of the front water jet grinding device and the spacing between two adjacent drainage knives of the water jet grinding device; the intelligent positioning module is arranged at the front end of the water jet grinding module, and there is a distance between each other; the intelligent positioning module is used to collect the surface image of the rail in advance and transmit the surface image of the rail to the grinding vehicle control center; the grinding vehicle control center controls the opening and closing time of each drainage knife nozzle on the water jet grinding module and the nozzle airflow focusing point according to the installation position parameters of the intelligent positioning module, the arrangement position of the water jet grinding module water jet and the driving speed of the grinding vehicle, thereby completing the grinding task of each water jet and realizing precise control of the rail grinding.

[0049] The water jet grinding vehicle includes a bogie running on the steel rail to be ground, a frame arranged on the bogie and a body arranged on the frame; the body includes a cab, a first machine room and a second machine room arranged in sequence from front to back; the cab electric control cabinet is used to control the power supply of the grinding vehicle; the grinding vehicle control center, the driver's seat and the cab electric control cabinet are all arranged in the cab. The grinding vehicle power module includes a diesel engine, a generator set, a gearbox, a cooling unit, a power system control cabinet, a battery and a diesel tank; the diesel engine is used to provide power for the grinding vehicle to move forward; the generator set is used to provide continuous power for the grinding vehicle; the gearbox is used to provide different power outputs for the generator set; the cooling unit is used to prevent the power system from overheating; the power system control cabinet is used to control the power system; the battery is used to store electricity; the diesel tank is used to store fuel; the diesel engine, the generator set, the gearbox, the cooling unit and the power system control cabinet are all arranged in the first machine room; the battery and the diesel tank are arranged on the frame. The water jet grinding module includes an air compressor, a filter, an abrasive tank, a vacuum pump, a booster pump, a water tank and a water jet grinding device; the abrasive tank is used to store abrasives required for water jet grinding; the filter is connected to the abrasive tank to filter out abrasives that do not meet the requirements; abrasive pipelines are provided between the air compressor and the abrasive tank, and between the abrasive tank and the water jet grinding device; the air compressor is used to provide high-pressure air to the abrasive pipeline, provide power for the air brake of the grinding vehicle, and provide power for abrasive transmission for the water jet grinding device; the water tank is used to store water; The water tank, the booster pump, and the water jet grinding device are connected in sequence with a water pipeline; the vacuum pump is connected to the booster pump, the booster pump is connected to the water tank, and the water tank is connected to the water jet grinding device. The vacuum pump provides vacuum in the water pipeline, and the booster pump is used to boost the water in the water tank. After passing through the booster pump, the water pressure can reach a maximum of more than MPa and is mixed with the abrasive output by the abrasive tank to grind the rail; the air compressor, the filter, the abrasive tank, the vacuum pump, the booster pump, and the water tank are all arranged in the second machine room. The water jet grinding device includes multiple row cutters arranged side by side; each row cutter has a different cutting angle, which is used to grind different positions of the rail; the multiple row cutters are used to grind in sequence to complete the all-round repair of the rail; each water cutter of the water jet grinding device is equipped with a nozzle.

[0050] In the present invention, the hardening ability of the magnetic fluid is positively correlated with the magnetic induction intensity of the magnetic field generated by the field generator, and the function of the hardening ability of the magnetic fluid and the magnetic field induction intensity is η=k(μ-1)H 2, where η is the magnetic viscosity of the magnetic fluid, the greater the magnetic viscosity, the greater the hardness, k is the proportional coefficient, μ is the relative magnetic permeability of the magnetic fluid, and H is the magnetic field intensity. It can be seen from the above function that the gas injection section 102 of the present invention changes the hardness of the magnetic fluid, thereby changing the thickness of the inner wall of the gas injection section 102 along the axial direction, thereby adjusting the inclination angle of the inner wall along the axial direction, and then adjusting the focusing angle of the airflow to achieve the adjustment of the abrasive injection distance, while reducing the splashing of the abrasive during the polishing and ejection process.

[0051] Of course, in order to achieve the change of the inclination angle of the inner wall of the gas injection section 102 along the axial direction in the present invention, in another embodiment, the gas injection section 102 is made of magnetostrictive material, and a coil is sleeved along the axial direction on the outer periphery of the gas injection section 102. By applying different currents to the coil, the magnetostrictive material undergoes axial expansion and contraction deformation, that is, deformation along the radial direction. Different currents provide magnetic fields of different magnitudes, so that the gas injection section 102 undergoes different deformations. More specifically, in the present application, the thickness of the magnetostrictive material decreases from top to bottom in the axial direction. In this way, the deformation from top to bottom also decreases in sequence, thereby adjusting the tapered angle of the inner wall of the gas injection section 102. Of course, before the nozzle is used, the magnetostrictive material needs to be oriented so that the magnetostrictive material undergoes directional deformation under the action of the magnetic field.

[0052] According to another embodiment of the present invention, a rail water jet continuous adjustable grinding method is also provided, the method integrating the above-mentioned nozzle, comprising:

[0053] S1 starts the grinding vehicle, collects rail surface images through industrial cameras, and sends the rail surface images to the grinding vehicle control center through a signal transmitter;

[0054] The S2 grinding vehicle control center performs defect feature recognition on the received rail surface image through an image processing algorithm to obtain a rail defect feature data signal;

[0055] The S3 grinding vehicle control center marks the location of the rail disease and determines the rail damage according to the characteristic data signal of the rail disease, and identifies the driving parameters and grinding positioning parameters of the grinding vehicle at the same time;

[0056] The S4 grinding vehicle control center controls the automatic opening and closing of the nozzle of each water jet grinding device after reaching the location of the defect according to the location of the rail defect, the driving parameters of the grinding vehicle and the grinding positioning parameters. At the same time, when the nozzle is working, the grinding vehicle control center controls the field generator on the nozzle to generate a continuously adjustable solidified magnetic field according to the rail damage situation, and then changes the focusing angle of the nozzle airflow to adapt to the working mode compatible with the rail damage, thereby achieving all targeted grinding and repair tasks of the rail damage at the location of the defect.

[0057] Wherein, the grinding vehicle driving parameters in step S3 include the driving speed of the grinding vehicle;

[0058] The grinding positioning parameters include the distance between the industrial camera and the center position of the first row of row cutters of the frontmost water jet grinding device and the distance between two adjacent row cutters of the water jet grinding device.

[0059] Furthermore, the completion of all the grinding and repairing tasks at the locations of the defects in step S4 further includes the following steps:

[0060] The S41 grinding vehicle control center calculates the time required for the first drainage knife of the water jet grinding device to reach the location of the defect according to the driving speed of the grinding vehicle and the distance between the industrial camera and the center position of the first drainage knife of the front water jet grinding device, and controls the first drainage knife to automatically open and close the nozzle to complete the grinding task after reaching the location of the defect;

[0061] S42 The grinding vehicle control center calculates the time required for the second drainage knife to reach the defect after the first drainage knife completes the grinding task according to the driving speed of the grinding vehicle and the distance between two adjacent drainage knives, and controls the second drainage knife to automatically open and close the nozzle to complete the grinding task after reaching the location of the defect;

[0062] S43 and so on, the grinding control module of the grinding vehicle control center calculates the time required for each subsequent drainage knife to reach the defect in turn, and controls each subsequent drainage knife to automatically open and close the nozzle after reaching the location of the defect to complete the grinding task until all grinding and repair tasks at the location of the defect are completed.

[0063] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-pressure airflow-assisted water jet nozzle, characterized in that: include: Nozzle structure body; A high-pressure water inlet (1) is provided at an upper portion of the nozzle structure body and is arranged axially along the nozzle structure body; A solid abrasive channel (5) is provided on the side wall of the nozzle structure body; A solid-liquid two-phase mixing chamber (3) is disposed in the nozzle structure body, and the solid-liquid two-phase mixing chamber (3) is in communication with the high-pressure water inlet (1) and the solid abrasive channel (5); A sand pipe (8) is arranged at the lower part of the nozzle structure body, and the sand pipe (8) is connected to the solid-liquid two-phase mixing chamber (3); A high-pressure airflow module, comprising an air pipe channel (7), an annular hollow air pipe (9), and a gas injection section (102) which are connected in sequence, wherein the air pipe channel (7) is used to input an airflow of a specified air pressure to the gas injection section (102), and the gas injection section (102) is used to adjust the focusing angle of the airflow according to the grinding distance, so that the abrasive sprayed by the sand pipe (8) corrects the jet direction under the action of the airflow constraint; It also includes a field generator, which is arranged in the gas injection section (102) and is used to generate a continuously adjustable magnetic field; The gas injection section (102) comprises a magnetic fluid deformation wall, the magnetic fluid deformation wall is provided with a magnetic fluid cavity, the magnetic fluid cavity can be deformed, a magnetic fluid is provided in the magnetic fluid cavity, the hardness of the magnetic fluid can change with the change of the magnetic field strength of the magnetic field generated by the field generator, thereby changing the axial inner wall slope of the magnetic fluid deformation wall; The hardening ability of the magnetic fluid is positively correlated with the magnetic induction intensity of the magnetic field generated by the field generator. The function of the hardening ability of the magnetic fluid and the magnetic field induction intensity is: ,in, is the magnetic viscosity. The greater the magnetic viscosity, the greater the hardness. is the proportionality coefficient, is the magnetic permeability of the magnetic fluid, H is the magnetic field strength; The field generator comprises an electromagnetic coil, which is arranged in the magnetic fluid cavity. The electromagnetic coil can generate a continuously adjustable magnetic field according to the current density flowing inside. The magnetic induction intensity of the magnetic field excited by the electromagnetic coil and the function of the current density flowing in the electromagnetic coil are: ,in, S is any closed curve in space, J is the current density in the energized coil, L is the boundary of the closed curve.

2. A high-pressure airflow-assisted water jet nozzle according to claim 1, characterized in that: A gas convergence tube (101) is further provided between the annular air tube (9) and the gas injection section (102); the gas convergence tube (101) is a conical structure; the annular cross section of the annular air tube (9) is larger than the annular cross section of the gas injection section (102).

3. The high-pressure airflow-assisted water jet nozzle according to claim 1, characterized in that: The current density flowing through the electromagnetic coil is positively correlated with the current flowing through the electromagnetic coil, and its function is: J , I is the current flowing through the electromagnetic coil, π is the circumference of a circle, r is the radius of the electromagnetic coil.

4. A high-pressure airflow-assisted water jet nozzle according to claim 3, characterized in that: A plurality of electromagnetic coils are provided, and the plurality of electromagnetic coils are arranged in the gas injection section (102). Currents of different magnitudes can flow through each electromagnetic coil, so as to form magnetic fluids of continuous different hardnesses in the gas injection section (102).

5. A rail water jet continuous adjustable grinding method, implemented by using the nozzle according to any one of claims 1 to 4, characterized in that: include: S1 starts the grinding vehicle, collects rail surface images through industrial cameras, and sends the rail surface images to the grinding vehicle control center through a signal transmitter; The S2 grinding vehicle control center performs defect feature recognition on the received rail surface image through an image processing algorithm to obtain a rail defect feature data signal; The S3 grinding vehicle control center marks the location of the rail disease and determines the rail damage according to the characteristic data signal of the rail disease, and identifies the driving parameters and grinding positioning parameters of the grinding vehicle at the same time; The S4 grinding vehicle control center controls the automatic opening and closing of the nozzle of each water jet grinding device after reaching the location of the defect according to the location of the rail defect, the driving parameters of the grinding vehicle and the grinding positioning parameters. At the same time, when the nozzle is working, the grinding vehicle control center controls the field generator on the nozzle to generate a continuously adjustable solidified magnetic field according to the rail damage situation, and then changes the focusing angle of the nozzle airflow to adapt to the working mode compatible with the rail damage, thereby achieving all targeted grinding and repair tasks of the rail damage at the location of the defect.

6. A rail water jet continuous adjustable grinding method according to claim 5, characterized in that: The grinding vehicle driving parameters in step S3 include the driving speed of the grinding vehicle; The grinding positioning parameters include the distance between the industrial camera and the center position of the first row of row cutters of the frontmost water jet grinding device and the distance between two adjacent row cutters of the water jet grinding device.

7. A rail water jet continuous adjustable grinding method according to claim 5, characterized in that: The completion of all the grinding and repair tasks at the location of the defect in step S4 also includes the following steps: The S41 grinding vehicle control center calculates the time required for the first drainage knife of the water jet grinding device to reach the location of the defect according to the driving speed of the grinding vehicle and the distance between the industrial camera and the center position of the first drainage knife of the front water jet grinding device, and controls the first drainage knife to automatically open and close the nozzle to complete the grinding task after reaching the location of the defect; S42 The grinding vehicle control center calculates the time required for the second drainage knife to reach the defect after the first drainage knife completes the grinding task according to the driving speed of the grinding vehicle and the distance between two adjacent drainage knives, and controls the second drainage knife to automatically open and close the nozzle to complete the grinding task after reaching the location of the defect; S43 and so on, the grinding control module of the grinding vehicle control center calculates the time required for each subsequent drainage knife to reach the defect in turn, and controls each subsequent drainage knife to automatically open and close the nozzle after reaching the location of the defect to complete the grinding task until all grinding and repair tasks at the location of the defect are completed.

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