CN114571373B - Spiral feeding device for machining corner structure and method for cooperatively regulating and controlling machining corner structure through feeding of abrasive and track - Google Patents

Abstract

The invention provides a spiral feeding device for processing a corner structure and a method for cooperatively regulating and controlling feeding and track of abrasive materials for processing the corner structure, wherein the feeding device comprises an air source, a storage tank, an abrasive material tank, a spiral feeding mechanism, an ECS control system and a bundling pipe; the air source is connected to the storage tank; the storage tank outlet is connected to the grinding tank; the screw feeding mechanism comprises a servo motor, a speed reducer, a sealing shell, an end cover, a sleeve, a green head and a screw; the servo motor and the bundling tube are electrically connected with the ECS control system; the sealing shell is sleeved outside the screw rod; the green head is connected to the abrasive canister; the grinding material spiral supply outlet at the bottom of the sealing shell is connected with the bundling pipe; the screw is divided into a feeding section, a compression section and a homogenizing section. The invention can effectively control the diameter of the high-energy beam jet flow column, prevent the workpiece from being 'overshot etched', and prevent the abrasive from being blocked by low-pressure backwater.

Description

Spiral feeding device for machining corner structure and method for cooperatively regulating and controlling machining corner structure through feeding of abrasive and track

Technical Field

The invention relates to the field of high-pressure abrasive water jet machining, in particular to a spiral feeding device for machining a corner structure and a method for machining the corner structure by means of cooperative regulation and control of abrasive feeding and tracks.

Background

The high-pressure abrasive water jet processing is to utilize the kinetic energy of the high-pressure water jet to carry tiny free abrasive particles to flow through a focusing pipe at an extremely high speed, form high-energy beams to be sprayed on the surface of a workpiece, carry out erosion, impact and damage, and realize the cutting and removal of workpiece materials, wherein whether the abrasive supply can be uniform and stable and can be controlled in real time directly influences the quality, efficiency and reliability of processed parts. Particularly, when the high-pressure abrasive water jet processing is performed on complex curved surfaces such as impellers and impeller discs, the parts are in a large-curvature structure at the corners of blade roots, so that the accurate supply and real-time adjustable requirements on abrasive are extremely high in order to avoid the phenomenon of over-cutting at the corners, the abrasive supply in an abrasive water jet processing system on the market mainly depends on the negative pressure formed by the rapid flow of high-pressure water through a bundling pipe to suck the abrasive, and the abrasive flow is controlled by manually adjusting the size of a valve port; on the one hand, this feeding necessarily results in a non-constant continuous flow of abrasive material, but rather a "pulsed" flow that is constantly "domed" and "slumped"; on the other hand, because the abrasive grain supply quantity is positively correlated with the diameter divergence degree of the high-energy beam jet flow column, when the large-curvature root of the complex curved surface parts such as impeller blades are processed, the abrasive grain supply quantity is required to be subjected to the addition/subtraction process at the curved surface corners of the track root by a numerical control machine tool, and at the moment, if the abrasive grain supply quantity cannot be controlled in real time, the divergent high-energy beam jet flow column not only can cause the root of the processed part to generate an over-cutting defect, but also part of abrasive grains can escape the high-energy beam jet flow column and generate secondary processing on the surface. In addition, when the air humidity is large or low-pressure backwater occurs, the abrasive is bound and agglomerated, so that the abrasive cannot be fully and uniformly mixed, and the blockage is easy to occur in a mixing cavity of the bundling pipe, thereby influencing the processing quality and the processing efficiency of the parts.

In summary, during abrasive water jet processing, the following defects mainly exist in the process of cooperative regulation and control of abrasive conveying and track:

1. the "pulsed" flow of "domes" and "slumps" results in abrasive supply rates that are difficult to control accurately;

2. the divergence degree of the high-energy Shu Sheliu column cannot be controlled in time, so that the processed part is damaged by secondary processing;

3. root "over-cuts" are easily created at large curvature corners when complex trajectory operations are performed;

4. the abrasive is easy to accumulate and cause transportation obstacle under the influence of air humidity and low-pressure backwater;

5. once the abrasive is blocked, the machine needs to be stopped for cleaning, so that the processing quality of the parts is greatly reduced.

Therefore, the design of the grinding material conveying device which can be accurately, uniformly and stably regulated in real time and is matched with the track to cooperatively regulate and control the processing of the part with the large curvature structure is an important link for realizing the application of the grinding material water jet on the part with the complex curved surface.

In the past patent inventions directed to accurate feeding of abrasives, there are a number of different types of examples:

chinese patent CN108940105a discloses a mixing device capable of precisely controlling the concentration of abrasive before jet, the device improves the abrasive water jet front mixing device about uniform mixing of abrasive and water, and the device is composed of an abrasive tank, a feeding rod, a driving mechanism, a helical blade and the like, and the feeding rod of the helical blade is dynamically driven by a servo motor to rotate so as to realize helical feeding, thereby eliminating jet turbulence phenomenon caused by air mixing in the mixing of abrasive and water, and further improving the stability of high-energy beam jet.

Chinese patent CN103831733a discloses an ultrasonic vibration assisted fluidization fine abrasive grain supply device, which relates to fluidization of abrasive grains under the dual actions of mechanical excitation and pulse airflow by adopting ultrasonic vibration, so as to solve the problem of abrasive blockage.

Chinese patent CN106272107a discloses a fine abrasive water jet pulse type magnetic abrasive feeding device, which consists of a stock bin, an air source, a pressure regulating valve, a stop valve, a pulse emitter, an electromagnetic control loop, an air supply pipe and a feeding pipe, and during operation, intermittent feeding is performed through the pulse emitter, so that the problems of feeding interruption and automatic feeding are effectively solved, and the processing precision is improved.

In the prior related patent technology, the problem of abrasive particle blockage is solved, and the method is more recently introduced in the case of abrasive water jet processing with the cooperation of the real-time adjustable accurate feeding and the track control of the abrasive for the corner part with large curvature.

Disclosure of Invention

In order to effectively solve the problems that abrasive supply is discontinuous, uneven, easy to block, high-energy beam jet flow column is dispersed to cause 'overshoot erosion' at the corner of a part, surface 'secondary processing' and the like in the process of processing a complex curved surface by abrasive water jet flow, the invention provides a spiral feeding device for processing a corner structure and a processing method for processing the corner structure by cooperative regulation and control of abrasive supply and tracks, so that the abrasive supply is continuous, uniform, stable and adjustable in real time, the purpose of effectively controlling the diameter of the high-energy beam jet flow column is achieved by regulating the abrasive supply quantity according to the track position of a bundling pipe, the workpiece is prevented from being 'overshoot eroded', and the abrasive blocking caused by low-pressure backwater can be prevented by a check valve.

The invention adopts the following technical means:

a spiral feeding device for processing a corner structure comprises an air source, a storage tank, a grinding tank, a spiral feeding mechanism, an ECS control system and a bundling pipe;

the air source is connected to the upper part of the storage tank through a pressure regulating valve; the pressure regulating valve is electrically connected with the ECS control system so as to regulate the air pressure in the storage tank; the bottom outlet of the storage tank is connected to the grinding tank;

the screw feeding mechanism comprises a servo motor, a speed reducer, a sealing shell, an end cover, a sleeve, a green head and a screw; the servo motor is connected with the speed reducer; the servo motor is electrically connected with the ECS control system, so that the rotating speed of the servo motor is controlled in real time; the end cover and the sleeve are fixedly arranged at the top of the sealed shell, and the sleeve is positioned in the end cover; the speed reducer is fixedly arranged on the end cover; the sealing shell is sleeved outside the screw rod; the main shaft of the speed reducer extends into the end cover, the top of the screw rod penetrates through the sealing shell and the sleeve and is fixedly connected with the main shaft of the speed reducer, and the sleeve is connected with a shaft shoulder at the upper part of the screw rod; the green head is arranged on the side surface of the sealed shell, one side of the green head is communicated with the inside of the sealed shell, and the other side of the green head is connected to the abrasive tank; the bottom of the sealing shell is provided with an abrasive spiral supply outlet; the abrasive spiral supply outlet is connected with the bundling pipe through a check valve; the bundling pipe is electrically connected with the ECS control system, so that the movement of the bundling pipe is controlled, and the positions of the bundling pipe and the radius of the high-energy beam jet column at the outlet are monitored in real time; the part of the screw rod for transporting the abrasive is divided into a feeding section, a compression section and a homogenizing section, wherein the diameter of the feeding section, the compression section and the homogenizing section gradually decrease along the abrasive transporting direction; the compression section is conical; the ratio k1 of the diameter D1 of the feeding section to the diameter D1 of the screw central rod positioned in the feeding section is equal to the ratio k2 of the diameter D2 of the homogenizing section to the diameter D2 of the screw central rod positioned in the homogenizing section, and the range of k1 and k2 is 2.5-3; the compression ratio i=d2/D1 of the screw ranges from 1.5 to 3; the screw groove depth H=0.55-0.7D1 of the feeding section; the inner side wall of the sealing shell is tightly attached to the edge of the screw rod.

Further, the taper alpha of the compression section is 15-20 degrees; the pitch d of the helical blade of the screw is 15 mm-20 mm; the screw thickness delta of the helical blade is 2 mm-4 mm; a plurality of exhaust holes with the diameter of 3 mm are uniformly formed in the spiral blades of the feeding section and the compression section; the inner side wall of the sealing shell is tightly attached to the edge of the spiral blade.

Further, the screw feed mechanism is vertically disposed.

Further, the shoulder height h of the screw is greater than 5 mm.

Further, the abrasive spiral supply outlet is equal in diameter to the abrasive inlet of the cluster tube.

Further, the surface of the spiral blade is provided with a wear-resistant material coating; the sleeve is made of wear-resistant aluminum bronze material; the screw is made of nitriding steel so as to enhance wear resistance; the sleeve is in clearance fit with the screw.

Further, the thickness of the sealed enclosure corresponding to the charging section is greater than 15 a mm a, and the thickness of the remainder of the sealed enclosure is less than 5a mm a.

Further, the range of the abrasive flow provided by the screw feeding mechanism is 0.04 kg/min-0.12 kg/min, and the radius range of the high-energy beam jet column formed at the position 3 mm away from the bundling tube outlet is 0.6-2.5 mm.

The invention also provides a method for processing the corner structure by cooperative regulation and control of the abrasive supply and the track, which adopts the spiral feeding device for processing the corner structure and specifically comprises the following steps:

opening a pressure regulating valve, forming pressure difference up and down in the storage tank through an air source, conveying the abrasive to the abrasive tank through an outlet at the bottom of the storage tank 3, and then flowing into a screw feeding mechanism through a green head; the ECS control system drives the servo motor to rotate, the servo motor drives the speed reducer to drive the screw rod to rotate, the grinding materials are extruded and transmitted along with the rotation of the screw rod, and finally the grinding materials flow into the bundling pipe through the grinding material spiral supply outlet;

the ECS control system is used for controlling the beam tube to move according to a planned track S input in the ECS control system in advance, the part to be processed is processed through the emitted high-energy beam jet column, the ECS control system monitors the radius r of the high-energy beam jet column at the outlet of the beam tube in real time, and the rotating speed of the servo motor is regulated and controlled, so that the radius r of the high-energy beam jet column emitted by the beam tube is regulated; when the ECS control system monitors that the radius R of the high-energy beam jet flow column provided by the bundling pipe is larger than the radius R of the corner of the part to be processed, and the bundling pipe moves to the corner position monitoring point LP of the part to be processed, a speed reducing signal is sent to the servo motor, the rotating speed of the servo motor is reduced, and therefore the abrasive conveying quantity is reduced, and the radius R of the high-energy beam jet flow column is reduced.

Compared with the prior art, the invention has the following advantages:

1. according to the spiral feeding device for processing the corner structure and the method for processing the corner structure by the cooperative regulation and control of the abrasive feeding and the track, the ECS control system is used for regulating the rotating speed of the servo motor according to the position and the outlet flow of the bundling pipe detected by the dynamic monitoring module so as to emit pulse signals, so that the problem of discontinuous abrasive feeding caused by the change of the rotating speed is reduced, the purpose of regulating the diameter of a high-energy beam jet flow column is achieved while the real-time regulation of the abrasive feeding is realized; the abrasive conveying quantity is controlled by the servo motor in a speed regulation way, so that the distribution state of the abrasive in the conveying cavity is optimized, the abrasive flow is uniform and stable, the 'pulse' supply of the abrasive is prevented, and the blocking phenomenon of the abrasive is eliminated.

2. According to the spiral feeding device for processing the corner structure and the method for processing the corner structure by the aid of the cooperation of the feeding and the track of the abrasive, the abrasive is further refined by pneumatic transportation on one hand and can be timely observed on the other hand by connecting the abrasive tank behind the storage tank, and the abrasive is prevented from blocking the spiral feeding mechanism.

For the reasons, the invention can be widely popularized in the field of high-pressure abrasive water jet machining.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings may be obtained according to the drawings without inventive effort to a person skilled in the art.

FIG. 1 is a schematic view of the spiral feeding device according to the present invention.

Fig. 2 is a schematic view of the screw feeding mechanism according to the present invention.

FIG. 3 is a schematic view of the structure of the screw according to the present invention.

Fig. 4 is a longitudinal cross-sectional view of the sealed enclosure of the present invention.

Fig. 5 is a schematic diagram of the trajectory when the high energy beam jet column radius R is smaller than the corner radius R of the part to be machined.

Fig. 6 is a schematic diagram of the root over-cutting principle when the radius R of the high-energy beam jet column is larger than the radius R of the corner of the part to be processed.

Fig. 7 is a schematic diagram of a track optimized by the processing method provided by the invention when the radius R of the high-energy beam jet column is larger than the radius R of the corner of the part to be processed.

In the figure: 1. a gas source; 2. a pressure regulating valve; 3. a storage tank; 4. grinding material tanks; 5. a screw feed mechanism; 6. an ECS control system; 7. a bundling tube; 8. a check valve; 5-1, a servo motor; 5-2, a speed reducer; 5-3, standing a bracket; 5-4, sealing the shell; 5-5, end covers; 5-6, flat key; 5-7, a sleeve; 5-8, exhaust holes; 5-9, green head; 5-10, screw rods; 5-11, helical blades; 5-12, a spiral feeding outlet of the grinding material; 5-13, limiting holes.

Detailed Description

It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other. The invention will be described in detail below with reference to the drawings in connection with embodiments.

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present invention. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. Meanwhile, it should be clear that the dimensions of the respective parts shown in the drawings are not drawn in actual scale for convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

In the description of the present invention, it should be understood that the azimuth or positional relationships indicated by the azimuth terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal", and "top, bottom", etc., are generally based on the azimuth or positional relationships shown in the drawings, merely to facilitate description of the present invention and simplify the description, and these azimuth terms do not indicate and imply that the apparatus or elements referred to must have a specific azimuth or be constructed and operated in a specific azimuth, and thus should not be construed as limiting the scope of protection of the present invention: the orientation word "inner and outer" refers to inner and outer relative to the contour of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "upper surface at … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial location relative to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the exemplary term "above … …" may include both orientations of "above … …" and "below … …". The device may also be positioned in other different ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In addition, the terms "first", "second", etc. are used to define the components, and are only for convenience of distinguishing the corresponding components, and the terms have no special meaning unless otherwise stated, and therefore should not be construed as limiting the scope of the present invention.

Example 1

The invention provides a spiral feeding device for processing a corner structure, and a method for cooperatively regulating and controlling the feeding and the track of an abrasive to process the corner structure, as shown in figures 1-4, and the spiral feeding device comprises an air source 1, a storage tank 3, an abrasive tank 4, a spiral feeding mechanism 5, an ECS control system 6 and a bundling pipe 7;

the air source 1 is connected to the upper part of the storage tank 3 through a pressure regulating valve 2; the pressure regulating valve 2 is electrically connected with the ECS control system 6, so that the air pressure in the storage tank 3 is regulated, and the storage tank 3 is ensured to inject the abrasive into the abrasive tank 4 under stable air pressure; the bottom outlet of the storage tank 3 is connected to the abrasive tank 4;

the screw feeding mechanism 5 comprises a servo motor 5-1, a speed reducer 5-2, a sealed shell 5-4, an end cover 5-5, a sleeve 5-7, a green head 5-9 and a screw 5-10; the servo motor 5-1 is connected with the speed reducer 5-2 and is used for increasing output torque; the servo motor 5-1 is electrically connected with the ECS control system 6, so that the rotating speed of the servo motor 5-1 is controlled in real time; the end cover 5-5 and the sleeve 5-7 are fixedly arranged at the top of the sealed shell 5-4 through screws, and the sleeve 5-7 is positioned in the end cover 5-5; the speed reducer 5-2 is fixedly arranged on the end cover 5-5; the sealing shell 5-4 is sleeved outside the screw 5-10 and used for positioning the radial direction of the screw 5-10; the main shaft of the speed reducer 5-2 extends into the end cover 5-5, the top of the screw 5-10 penetrates through the sealing shell 5-4 and the sleeve 5-7 and is fixedly connected with the main shaft of the speed reducer 5-2 through a flat key 5-6 and a locating pin, the axial direction of the flat key 5-6 is limited through a limiting hole 5-13 arranged on the screw 5-10, and the sleeve 5-7 is connected with a shaft shoulder at the upper part of the screw 5-10 and is used for locating the axial direction of the screw 5-10; the green head 5-9 is arranged on the side surface of the sealed shell 5-4, one side of the green head is communicated with the interior of the sealed shell 5-4, and the other side of the green head is connected to the abrasive tank 4; the bottom of the sealing shell 5-4 is provided with an abrasive spiral supply outlet 5-12; the abrasive spiral supply outlet 5-12 is connected with the bundling pipe 7 through a check valve 8, the check valve 8 is used for preventing the problem of abrasive particle clusters caused by low-pressure backwater, and the reliability and the controllability of the spiral feeding mechanism 5 are improved; the bundling pipe 7 is electrically connected with the ECS control system 6 so as to control the movement of the bundling pipe 7 and monitor the position of the bundling pipe 7 and the abrasive flow at the outlet in real time; the part of the screw 5-10 for transporting the abrasive is divided into a feeding section, a compression section and a homogenizing section with gradually reduced diameters along the abrasive transporting direction, so that the volume of the abrasive is continuously contracted in the transporting process, the gas content in the abrasive is reduced on one hand, and the transporting efficiency and the transporting precision of the abrasive are improved on the other hand; the compression section is conical; the ratio k1 of the diameter D1 of the feeding section to the diameter D1 of the central rod of the screw 5-10 positioned in the feeding section is equal to the ratio k2 of the diameter D2 of the homogenizing section to the diameter D2 of the central rod of the screw 5-10 positioned in the homogenizing section, namely k1=d1/D1, k2=d2/D2, and the range of k1 and k2 is 2.5-3; the compression ratio i=d2/D1 of the screw 5-10 ranges from 1.5 to 3 to improve the abrasive sustainable feeding ability; the screw groove depth H=0.55-0.7D1 of the feeding section is used for preventing the screw feeding mechanism 5 from being damaged due to larger transmission torque caused by blockage of materials; the inner side wall of the sealing shell 5-4 is tightly attached to the edge of the screw 5-10.

Further, the taper alpha of the compression section is 15-20 degrees. The pitch d of the spiral blade 5-11 of the screw 5-10 is 15 mm-20 mm; the screw thickness delta of the screw blade 5-11 is 2 mm-4 mm; the spiral blades 5-11 positioned on the feeding section and the compression section are uniformly provided with a plurality of exhaust holes 5-8 with the diameter of 3 mm, so that on one hand, the abrasive can be prevented from being blocked, and on the other hand, the air carried in the abrasive particle transportation can be effectively exhausted; the inner side wall of the sealing shell 5-4 is tightly attached to the edge of the spiral blade 5-11; the flow of the abrasive is further refined by designing the appropriate pitch d, screw compression ratio i and screw blade thickness delta, while the outflow of the abrasive from the mating gap of the screw blade 5-11 and the seal housing 5-4 is prevented when the operation is stopped.

Further, the screw feeding mechanism 5 further includes a stand 5-3 fixedly mounted to the end cap 5-5 by screws for supporting the entire mechanism.

Further, the screw feeding mechanism 5 is vertically arranged, so that the abrasive is facilitated to advance by means of self weight, and abrasion of the screw and the screw blade is reduced to a certain extent.

Further, the number of threads of the spiral blades 5-11 is 3-6, so that energy waste caused by larger resistance in the abrasive transmission process is prevented.

Further, the reduction ratio of the speed reducer 5-2 is 5:1-10:1, and the torque required by abrasive particle transmission is met.

Further, the shaft shoulder height h of the screw 5-10 is larger than 5 mm, so that abrasive particles are prevented from entering between the sleeve and the screw joint surface, and abrasion of the sleeve is reduced.

Furthermore, the diameters of the abrasive spiral supply outlets 5-12 are equal to those of the abrasive inlets of the bundling pipe 7, so that the abrasive is stably conveyed, the abrasive volume in unit time is ensured to be constant, and the abrasive spiral supply outlets are convenient to directly connect with a standard pneumatic interface and convenient to disassemble and assemble.

Further, the surfaces of the spiral blades 5-11 are provided with wear-resistant material coatings, so that the service time of the spiral shaft is prolonged; the sleeve 5-7 is made of wear-resistant aluminum bronze material; the screw 5-10 is made of nitriding steel so as to enhance wear resistance; the sleeve 5-7 is in clearance fit with the screw 5-10, and plays a role in supporting the axial stress of the screw 5-10.

Further, the thickness H1 of the seal housing 5-4 corresponding to the charging section is greater than 15 mm, so that the seal housing can be connected with the end cover 5-5 and the sleeve 5-7 by bolts, and the thickness H2 of the rest of the seal housing 5-4 is less than 5 mm for reducing the dead weight of the device.

Further, the flow rate of the abrasive provided by the screw feeding mechanism 5 ranges from 0.04 kg/min to 0.12 kg/min, and the radius of the high-energy beam jet column formed at the position 3 mm away from the outlet of the bundling tube 7 ranges from 0.6 to 2.5 mm.

Further, the screw 5-10, the sealing shell 5-4, the sleeve 5-7 and the servo motor 5-1 are coaxially arranged, and the sleeve 5-7 is connected with the sealing shell 5-4 through short round head screws which are uniformly distributed in an annular mode; in order to reduce vibration of the whole device caused by rotation of the servo motor 5-1, the end cover 5-5 is directly connected with the sealing shell 5-4 through long hexagon socket head cap screws.

Aiming at the large-curvature corner parts processed by abrasive water jet, the spiral feeding device provided by the invention combines pneumatic conveying and spiral conveying of the abrasive, reasonably designs the compression ratio of the screw and the depth of the screw groove, optimizes the distribution state of the abrasive in the spiral feeding and feeding cavity, and ensures that the abrasive is uniformly and stably conveyed; the spiral feeding mechanism is vertically arranged, and the self weight of the spiral blade and the abrasive is utilized to drive the abrasive to flow, so that the abrasive is further prevented from blocking the feeding cavity; in the processing process, the rotating speed of the servo motor is further adjusted in real time according to the track position of the bundling tube, and the purpose of controlling the diameter of the high-energy beam jet flow column is achieved by adjusting the abrasive feeding amount; the application and development of the high-pressure abrasive water jet technology on the machining of complex curved surface parts are promoted.

The high-energy beam jet column provided by the beam gathering pipe 7 has a certain diameter, the diameter is not negligible in the processing process, particularly in the processing of complex curved surface corners, the diameter directly determines the quality of the corners, and due to the influence of the high-energy beam jet column, the planned track S and the actual track T have a certain deviation, and the actual track T is formed by accumulating innumerable high-energy beam jet columns with a certain radius; the radius r of the high-energy beam jet column is a variable influenced by a plurality of factors, and r is the comprehensive result of the water pressure P, the target distance s, the abrasive flow Q and the abrasive grain diameter u:

however, according to the prior literature, the influence ratio of the abrasive flow rate on the radius r of the high-energy beam jet column is the largest in the above variables, namely, the radius r of the high-energy beam jet column depends on the abrasive flow rate in unit time, therefore, the invention also provides a method for cooperatively regulating and controlling the processing corner structure by using the abrasive supply and the track, which adopts the spiral feeding device for processing the corner structure by using the abrasive water jet, and specifically comprises the following steps:

the screw feeding mechanism 5 is vertically arranged at a proper position through the screw matching vertical support 5-3, the pressure regulating valve 2 is opened, the inside of the storage tank 3 is formed into pressure difference up and down through the air source 1, the abrasive is conveyed to the abrasive tank 4 through the outlet at the bottom of the storage tank 3, and then flows into the screw feeding mechanism 5 through the grids Lin Tou 5-9; the ECS control system 6 drives the servo motor 5-1 to rotate, the servo motor 5-1 drives the speed reducer 5-2 to drive the screw 5-10 to rotate, along with the rotation of the screw 5-10, the spiral blade 5-11 extrudes and transmits the abrasive, the diameter of the screw 5-10 and the diameter of the spiral blade 5-11 are continuously reduced in the process of continuously transporting the abrasive downwards in the sealed shell 5-4, the space for transporting the abrasive is continuously reduced, the interval between abrasive particles is continuously reduced under the extrusion action of the spiral blade, the gas mixed in the abrasive is gradually discharged through the exhaust hole 5-8 on the spiral blade 5-11, the abrasive flow is continuously and evenly stable when the abrasive is forwards transported under the rotation action of the screw 5-10, and finally the abrasive flows into the bundling tube 7 through the abrasive spiral supply outlet 5-12, so that the 'pulse' flow of the abrasive is effectively avoided;

the ECS control system 6 is used for controlling the beam tube 7 to move according to a planned track S input in the ECS control system 6 in advance, the part to be processed is processed through the emitted high-energy beam jet column, the ECS control system 6 monitors the radius r of the high-energy beam jet column at the outlet of the beam tube 7 in real time, and the rotating speed of the servo motor 5-1 is regulated and controlled, so that the radius r of the high-energy beam jet column emitted by the beam tube 7 is regulated;

when the ECS control system 6 monitors that the radius R of the high-energy beam jet flow column provided by the bundling pipe 7 is larger than the radius R of the corner of the part to be processed, and the bundling pipe 7 moves to a corner position monitoring point LP of the part to be processed, a speed reducing signal is sent to the servo motor 5-1, and the rotating speed of the servo motor 5-1 is reduced, so that the conveying amount of abrasive materials is reduced, and the radius R of the high-energy beam jet flow column is reduced;

specifically, as shown in fig. 6, when the ECS control system 6 monitors that the radius R of the high-energy beam jet column provided by the cluster tube 7 is greater than the corner radius R of the part to be processed, and the planned trajectory S is biased outwards, the cluster tube 8 will process according to the actual trajectory T shown in the figure, if the abrasive flow is not changed, it can be seen that the overlapping effect of the high-energy beam jet column at the corner will inevitably generate "overstock" at the corner portion, so that a complete corner structure cannot be obtained; therefore, when the cluster pipe 8 moves to the corner position monitoring point LP of the part to be processed, the method provided by the invention can enable the ECS control system 6 to adjust the rotating speed of the servo motor 5-1, and reduce the rotating speed of the screw 5-10 by reducing the rotating speed of the servo motor 5-1 so as to reduce the abrasive conveying quantity of the helical blade 5-11, thereby achieving the purpose of reducing the high-energy beam jet column, and as shown in figure 7, the phenomenon of over-cutting can be avoided by timely changing the diameter of the high-energy beam jet column;

when the radius R of the high-energy beam jet column provided by the bundling tube 7 is smaller than the radius R of the corner of the part to be processed, and the device and the method provided by the invention are adopted to process the corner structure, the bundling tube 8 is processed according to the outwards biased actual track T1 or the inwards biased actual track T2 relative to the planned track S, as shown in figure 5, in this case, the bundling tube 8 can process the planned track S according to the biased actual track T1/T2, so that the rotation speed of the servo motor 5-1 can be selected not to be changed to enable the bundling tube 7 to continue to move to complete the processing of the corner part.

Experiments prove that when the large-curvature corner parts are processed, the feeding device disclosed by the invention can uniformly and stably change the abrasive quantity while rapidly responding, so that abrasive blockage is not easy to form, pulse feeding of abrasive is avoided, and low-pressure backwater is prevented from causing abrasive clusters to reduce the service life of the abrasive feeding device.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced with equivalents; such modifications and substitutions do not depart from the spirit of the technical solutions according to the embodiments of the present invention.

Claims (9)

1. The spiral feeding device for machining the corner structure is characterized by comprising an air source, a storage tank, a grinding tank, a spiral feeding mechanism, an ECS control system and a bundling pipe;

the air source is connected to the upper part of the storage tank through a pressure regulating valve; the pressure regulating valve is electrically connected with the ECS control system so as to regulate the air pressure in the storage tank; the bottom outlet of the storage tank is connected to the grinding tank;

the screw feeding mechanism comprises a servo motor, a speed reducer, a sealing shell, an end cover, a sleeve, a green head and a screw; the servo motor is connected with the speed reducer; the servo motor is electrically connected with the ECS control system, so that the rotating speed of the servo motor is controlled in real time; the end cover and the sleeve are fixedly arranged at the top of the sealed shell, and the sleeve is positioned in the end cover; the speed reducer is fixedly arranged on the end cover; the sealing shell is sleeved outside the screw rod; the main shaft of the speed reducer extends into the end cover, the top of the screw rod penetrates through the sealing shell and the sleeve and is fixedly connected with the main shaft of the speed reducer, and the sleeve is connected with a shaft shoulder at the upper part of the screw rod; the green head is arranged on the side surface of the sealed shell, one side of the green head is communicated with the inside of the sealed shell, and the other side of the green head is connected to the abrasive tank; the bottom of the sealing shell is provided with an abrasive spiral supply outlet; the abrasive spiral supply outlet is connected with the bundling pipe through a check valve; the bundling pipe is electrically connected with the ECS control system, so that the movement of the bundling pipe is controlled, and the positions of the bundling pipe and the radius of the high-energy beam jet column at the outlet are monitored in real time; the part of the screw rod for transporting the abrasive is divided into a feeding section, a compression section and a homogenizing section, wherein the diameter of the feeding section, the compression section and the homogenizing section gradually decrease along the abrasive transporting direction; the compression section is conical; the ratio k1 of the diameter D1 of the feeding section to the diameter D1 of the screw central rod positioned in the feeding section is equal to the ratio k2 of the diameter D2 of the homogenizing section to the diameter D2 of the screw central rod positioned in the homogenizing section, and the range of k1 and k2 is 2.5-3; the compression ratio i=d2/D1 of the screw ranges from 1.5 to 3; the screw groove depth H=0.55-0.7D1 of the feeding section; the inner side wall of the sealing shell is tightly attached to the edge of the screw;

when the ECS control system monitors that the radius of the high-energy beam jet flow column provided by the bundling pipe is larger than the radius of a corner of a part to be processed, and the bundling pipe moves to a corner position monitoring point LP of the part to be processed, a speed reducing signal is sent to the servo motor, and the rotating speed of the servo motor is reduced, so that the conveying amount of abrasive materials is reduced, and the radius of the high-energy beam jet flow column is reduced.

2. The screw feeder for machining corner structures of claim 1, wherein the taper α of the compression section is 15 ° -20 °; the pitch d of the helical blade of the screw is 15 mm-20 mm; the screw thickness delta of the helical blade is 2 mm-4 mm; a plurality of exhaust holes with the diameter of 3 mm are uniformly formed in the spiral blades of the feeding section and the compression section; the inner side wall of the sealing shell is tightly attached to the edge of the spiral blade.

3. A screw feeder for machining corner structures according to claim 1, wherein the screw feeder is vertically disposed.

4. The screw feeder for machining corner structures of claim 1, wherein the shoulder height h of the screw is greater than 5 mm.

5. The spiral feeder for machining corner structures of claim 1, wherein the abrasive spiral feed outlet is equal in diameter to the abrasive inlet of the cluster tube.

6. A screw feeder for machining corner structures according to claim 2, wherein the surface of the screw blade is coated with a wear resistant material; the sleeve is made of wear-resistant aluminum bronze material; the screw is made of nitriding steel so as to enhance wear resistance; the sleeve is in clearance fit with the screw.

7. The screw feeder for machining corner structures according to claim 1, wherein the thickness of the sealed enclosure corresponding to the feed section is greater than 15 a mm a, the remainder of the sealed enclosure being less than 5a mm a.

8. The screw feeder for machining corner structures according to claim 1, wherein the screw feeder provides an abrasive flow rate in the range of 0.04 kg/min to 0.12 kg/min and a high energy beam jet column radius in the range of 0.6 to 2.5 mm formed at a distance of 3 mm from the cluster tube outlet.

9. A method for processing a corner structure by means of cooperation of abrasive feeding and trajectory control, which adopts the spiral feeding device for processing a corner structure according to any one of claims 1-8, and is characterized by comprising the following steps:

opening a pressure regulating valve, forming pressure difference up and down in the storage tank through an air source, conveying the abrasive to the abrasive tank through an outlet at the bottom of the storage tank, and then flowing into a screw feeding mechanism through a green head; the ECS control system drives the servo motor to rotate, the servo motor drives the speed reducer to drive the screw rod to rotate, the grinding materials are extruded and transmitted along with the rotation of the screw rod, and finally the grinding materials flow into the bundling pipe through the grinding material spiral supply outlet;

the ECS control system is used for controlling the beam tube to move according to a planned track S input in the ECS control system in advance, the part to be processed is processed through the emitted high-energy beam jet column, the ECS control system monitors the radius r of the high-energy beam jet column at the outlet of the beam tube in real time, and the rotating speed of the servo motor is regulated and controlled, so that the radius r of the high-energy beam jet column emitted by the beam tube is regulated; when the ECS control system monitors that the radius R of the high-energy beam jet flow column provided by the bundling pipe is larger than the radius R of the corner of the part to be processed, and the bundling pipe moves to the corner position monitoring point LP of the part to be processed, a speed reducing signal is sent to the servo motor, the rotating speed of the servo motor is reduced, and therefore the abrasive conveying quantity is reduced, and the radius R of the high-energy beam jet flow column is reduced.

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