Novel gear repairing device and method based on high-energy beam

Abstract

The invention belongs to the field of gear laser repairing, and provides a novel gear repairing device and method based on a high-energy beam, the device comprises a high-energy beam generator, a working head, a base, a powder feeder, an indexing mechanism and a three-axis moving mechanism; a three-axis moving mechanism is arranged on the base, the three-axis moving mechanism is connected with a working head, the output ends of the high-energy beam generator and the powder feeder are integrated on the working head, the working head faces a to-be-repaired gear, and the position of the working head is adjusted through the three-axis moving mechanism so that the output ends of the high-energy beam generator and the powder feeder can face a to-be-repaired area of the to-be-repaired gear; according to the laser high-energy beam repairing technology, the bonding strength of a cladding layer and a base body is high, and the wear resistance of the tooth surface of the gear is improved; during gear repairing, the geometric dimension of a workpiece is recovered, meanwhile, synchronous surface strengthening can be achieved, the comprehensive use performance of the gear is improved, and the service life of the gear is prolonged; and a heat affected zone and thermal deformation of a repaired part are small, and the metal performance of a workpiece matrix is not changed.

Description

Technical Field

[0001] The invention belongs to the field of gear laser repair, and in particular relates to a novel gear repair device and method based on high-energy beam. Background Art

[0002] Under extreme conditions of high speed, impact and heavy load, if the number of teeth and module of the gear are large, the tooth surface will suffer different degrees of damage such as pitting and wear after long-term operation, thus affecting the transmission efficiency. In this case, it is obviously uneconomical to scrap and replace the gear with a new one.

[0003] Traditional repair processes mainly include traditional brush plating, spraying, and surfacing. Brush plating equipment is simple and flexible to operate, but its repair efficiency is low and it is only suitable for repairing local damage of small area and small thickness. In addition, the repair layer is mechanically bonded to the substrate and is easy to peel off during service. Although spraying is more efficient, the repair layer is still mechanically bonded to the substrate, and the repair layer presents a multi-layer porous and uneven structure. Obviously, these two repair processes cannot be applied to extreme working conditions of high speed, impact, and heavy load. Although traditional surfacing can obtain a metallurgically bonded repair layer, due to the high heat input, there are also problems such as large welding deformation, large heat-affected zone, and high dilution rate. It is not suitable for the repair of precision parts.

[0004] The present invention uses laser high-energy beam cladding repair technology to quickly and accurately repair gear tooth surfaces, which has its unique advantages. High-energy beam cladding remanufacturing technology is a new material forming technology that uses laser high-energy density beam as a heat source combined with the idea of ​​digital discrete stacking to perform material additive repair and manufacturing. High-energy beam additive remanufacturing technology has a series of advantages such as small heat-affected zone, high precision, and no restrictions on part structure and materials. It is particularly suitable for rapid manufacturing and repair of high-strength, high-hardness, high-corrosion-resistant, and complex-structured metal parts serving under extreme working conditions. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a new gear repair device and method based on high energy beam to solve the problems in the prior art. The technical solution adopted by the present invention is: A novel gear repair device based on high energy beam, comprising a high energy beam generator, a working head, a base, a powder feeder, a dividing mechanism and a three-axis moving mechanism; The three-axis moving mechanism is arranged on the base, the three-axis moving mechanism is connected to the working head, the output ends of the high-energy beam generator and the powder feeder are integrated on the working head, the working head faces the gear to be repaired, and the working head adjusts its position through the three-axis moving mechanism so that the output ends of the high-energy beam generator and the powder feeder face the to-be-repaired area of ​​the gear to be repaired; The gear to be repaired is mounted on the indexing mechanism, which is arranged on the base. The indexing mechanism is used to drive the gear to be repaired to rotate, and each rotation angle is the pitch angle of the gear to be repaired.

[0006] Furthermore, the three-axis moving mechanism includes a support, a lifting block, a lateral movement block, a front and rear guide rail, a lifting guide rail and a lateral movement guide rail; The bottom of the pillar is connected to the base via front and rear guide rails; the side of the pillar is connected to the lifting block via a lifting guide rail; the lifting block is connected to the lateral movement block via a lateral movement guide rail; and the working head is fixedly connected to the lateral movement block.

[0007] Furthermore, the indexing mechanism includes a motor, a spindle, a housing, a driven rod and a cam; The motor is mounted on the housing, the output end of the motor is fixedly connected to the cam, the cam is located in the housing, and the bottom of the driven rod is set within the rotation range of the cam; the main shaft is rotatably connected to the housing, the bottom of the main shaft and the bottom of the driven rod are both located in the housing; the top of the main shaft passes through the housing and is connected to the gear to be repaired; The cam is used to push the driven rod to rotate around the main shaft, so that the main shaft drives the gear to be repaired to rotate at the angle of its tooth pitch angle.

[0008] Furthermore, the indexing mechanism also includes a reset assembly, a driven sleeve, an elastic ejector rod, a pawl and a driven wheel; The driven rod is connected to the box body through the reset assembly, so as to reset the driven rod when it is not in contact with the cam; the side surface of the driven rod is fixedly connected to the outer side surface of the driven sleeve through a connecting rod; The driven sleeve is sleeved on the main shaft, the driven sleeve is rotatably connected to the box body, the inner side surface of the driven sleeve is rotatably connected to one end of the pawl, the other end of the pawl is clamped in the tooth groove of the driven wheel, the driven wheel is sleeved on the main shaft, the elastic push rod is installed on the side wall of the driven sleeve, and the end of the elastic push rod abuts against the outer side of the pawl.

[0009] Furthermore, the elastic ejector rod comprises a connecting bolt, a connecting head, an elastic sleeve and a bendable elastic member; The connecting bolt is threadedly connected to the side wall of the driven sleeve, the end of the connecting bolt is detachably connected to the connecting head, the end of the connecting head is connected to the elastic sleeve, the bendable elastic member is arranged in the elastic sleeve, and the end of the elastic sleeve abuts against the outer side of the pawl.

[0010] Further, the reset assembly includes an arc-shaped rod, an arc-shaped opening, an arc-shaped inner hole and an elastic component; The top of the box body is provided with the arc-shaped inner hole, one end of the arc-shaped inner hole is provided with the arc-shaped opening, and the arc-shaped rod, the arc-shaped inner hole, the driven sleeve and the main shaft are coaxially arranged; One end of the arc rod is arranged in the arc inner hole, the elastic component is arranged in the arc inner hole, the elastic component abuts against the arc rod, and the other end of the arc rod is fixedly connected to the driven rod, and the driven rod is located in the arc opening.

[0011] Furthermore, the top opening of the box body is detachably connected to a double-layer cover plate, and the double-layer cover plate includes two plate bodies, and arc grooves are arranged on opposite sides of the two plate bodies, and the two arc grooves are arranged opposite to each other to jointly form the arc-shaped inner hole.

[0012] A gear repair method based on high energy beam, the method comprising: Step 1, installing a detection and identification module on the working head; Step 2: the indexing mechanism drives the gear to be repaired to rotate, and the detection and recognition module identifies the area to be repaired of the gear to be repaired; Step 3, adjusting the position of the working head through the three-axis moving mechanism so that the output ends of the high-energy beam generator and the powder feeder face the area to be repaired of the gear to be repaired; In step 4, the high energy beam generator and the powder feeder work simultaneously to generate a high energy beam and powder onto the area to be repaired, thereby forming a cladding layer to repair the gear.

[0013] Furthermore, the detection and identification module includes a multi-spectral industrial camera array and a laser displacement sensor; In the step 2, when the area to be repaired of the gear to be repaired is identified by the detection and identification module, the following steps are included: Step 2.1, establish a multi-camera array geometric projection model: Set up k The transformation matrix from the camera coordinate system to the world coordinate system is ,in is the rotation matrix, is the translation vector; The imaging formula is: , in is the camera intrinsic parameter matrix, and is the pixel coordinate, X w ，Y w ，Z w is the world coordinate; Step 2.2, multispectral fusion: for each pixel Weighted fusion of spectral intensities in N bands: , Weight Optimize allocation according to defect-sensitive bands; Step 2.3, laser 3D profile measurement: The laser line of the laser displacement sensor is projected onto the surface of the gear to be repaired (2), and the reflected light spot is at the sensor imaging position. With height Relationship: , in, is the baseline distance, is the laser emission angle, is the focal length of the lens; Combined gear rotation angle , convert the 2D laser profile into a 3D point cloud: , in, is the radial distance; Step 2.4, the raw data collected by the multispectral industrial camera array and the laser displacement sensor are preprocessed in real time through the edge computing node; Step 2.5, feature extraction is performed through a defect recognition model based on a deep convolutional neural network of the ResNet-50 architecture. For the defect recognition model, a loss function is set. The loss function is combined with the FocalLoss loss function and the DiceLoss loss function to obtain a total loss function. Step 2.6, synchronize the data of the multi-spectral industrial camera array and the laser displacement sensor in time and align them in space. Through calibration, unify the data of each sensor to the same coordinate, and then use the Kalman filter formula to obtain more accurate coordinates, so as to realize the positioning of the coordinates of the repair area of ​​the gear to be repaired (2).

[0014] Furthermore, in step 2.5, the FocalLoss loss function is expressed by the following formula: , in, is the modulation factor, Used to adjust the ratio between positive and negative sample losses. is an adjustable focus parameter; The DiceLoss function is expressed by the following formula: , is the value of the i-th pixel predicted by the model, is the value of the i-th pixel of the true label, is the smoothing coefficient; The total loss function is expressed by the following formula: , in, ; is the scale factor.

[0015] The present invention has the following beneficial effects: the cladding layer of the laser high-energy beam repair technology of the present invention has high bonding strength with the substrate, which increases the wear resistance of the gear tooth surface; while restoring the geometric dimensions of the workpiece, the gear repair can achieve synchronous surface strengthening, thereby improving the comprehensive performance and service life of the gear; the heat-affected zone and thermal deformation of the repaired part are small, and the metal properties of the workpiece substrate are not changed; the cladding layer can achieve customization of the workpiece surface properties, such as corrosion resistance, wear resistance, and high temperature resistance; the heat-affected zone and thermal deformation of the repaired part are small, and the metal properties of the workpiece substrate are not changed; the cladding layer can achieve customization of the workpiece surface properties, such as corrosion resistance, wear resistance, and high temperature resistance. The repair process is automatically controlled by the machine, which ensures the quality of the workpiece while greatly improving the repair efficiency, and the construction period can be greatly shortened. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a structural schematic diagram of the indexing mechanism; Figure 3 Schematic diagram of the pawl connection relationship Figure 4 for Figure 3 The enlarged schematic diagram at A in the middle; Figure 5 is a schematic diagram of an arc-shaped opening; Figure 6 Schematic diagram of the connection relationship of the arc rod; In the figure: control system 1, gear to be repaired 2, high energy beam generator 3, detection and identification module 4, working head 5, pillar 6, base 7, powder feeder 8, lifting block 9, lateral block 10, bracket 11, indexing mechanism 12, motor 121, main shaft 122, elastic component 123, double-layer cover plate 124, box body 125, connecting rod 126, driven rod 127, cam 128, arc-shaped inner hole 129, driven sleeve 130, elastic push rod 131, pawl 132, driven wheel 133, damping seat 134, arc-shaped rod 135, arc-shaped opening 136, slider 137, connecting bolt 1310, connecting head 1311, elastic sleeve 1312, bendable elastic member 1313. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention Figure 1-Figure 6, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. It should be noted that, unless otherwise specified, the "detachable connection" of the present invention can be achieved by bolts, buckles, etc.

[0018] like Figure 1 , one A novel gear repair device based on high energy beam, comprising a high energy beam generator 3, a working head 5, a base 7, a powder feeder 8, a dividing mechanism 12 and a three-axis moving mechanism; The three-axis moving mechanism is arranged on the base 7, and the three-axis moving mechanism is connected to the working head 5. The output ends of the high-energy beam generator 3 and the powder feeder 8 are integrated on the working head 5. The working head 5 faces the gear 2 to be repaired. The working head 5 adjusts its position through the three-axis moving mechanism so that the output ends of the high-energy beam generator 3 and the powder feeder 8 face the repair area of ​​the gear 2 to be repaired. The gear 2 to be repaired is mounted on the indexing mechanism 12 , and the indexing mechanism 12 is arranged on the base 7 . The indexing mechanism 12 is used to drive the gear 2 to be repaired to rotate, and each rotation angle is the pitch angle of the gear 2 to be repaired.

[0019] The base 7 is the basic mounting seat of the present invention. The high-energy beam generator 3 and the powder feeder 8 are both prior art. The high-energy beam generator 3 is a laser, and the high-energy beam is a laser beam. The energy and focusing degree of the laser beam are adjusted by the control system 1 to meet the requirements of different materials and damage characteristics. The powder feeder 8 is prior art, and the powder feeder 8 usually includes a powder storage tank, a powder feeding pipe and other components, which are responsible for uniformly and continuously conveying the metal powder to the working head 5. The output end of the high-energy beam generator 3 is a laser head, and the output end of the powder feeder 8 is a nozzle. The nozzle and the laser head are both fixed on the working head 5. The working head 5 can be a frame, a plate, a block or other structures. The nozzle and the laser head are fixed by means of buckles, pipe clamps, etc. to achieve the spatiotemporal synchronization of the powder flow and the energy beam.

[0020] In one embodiment of the present invention, through the control of the control system 1, the three-axis moving mechanism enables the working head 5 to accurately irradiate the damaged part of the gear according to the preset path. The high-energy beam interacts with the powder material to remove the damaged layer by melting, evaporation or chemical reaction, and promotes the formation of new tissue or the deposition of filling materials. The high-energy beam melts the powder and the substrate at the same time to form a cladding layer. The cladding layer and the substrate of the area to be repaired are metallurgically bonded, dense and have high bonding strength. After repairing one tooth surface, the gear 2 to be repaired is driven to rotate by the dividing mechanism 12 so that the next tooth surface of the gear 2 to be repaired faces the working head 5. The function of the dividing mechanism 12 is to allow the repaired gear 2 to rotate its pitch angle each time, so that each tooth surface of the repaired gear 2 passes through the working head 5 alternately. In the present invention, the pitch angle is the angle between two adjacent teeth of the repaired gear 2.

[0021] The high-energy beam repair technology of the present invention has a high bonding strength between the cladding layer and the substrate, which increases the wear resistance of the gear tooth surface; while restoring the geometric dimensions of the workpiece, gear repair can achieve synchronous surface strengthening, improve the comprehensive performance and service life of the gear; the heat-affected zone and thermal deformation of the repaired part are small, and the metal properties of the workpiece substrate are not changed; the cladding layer can realize the customization of the workpiece surface properties, such as corrosion resistance, wear resistance, high temperature resistance, etc.; the heat-affected zone and thermal deformation of the repaired part are small, and the metal properties of the workpiece substrate are not changed; the cladding layer can realize the customization of the workpiece surface properties, such as corrosion resistance, wear resistance, high temperature resistance, etc. The repair process is automatically controlled by the machine, which ensures the quality of the workpiece while greatly improving the repair efficiency, and the construction period can be greatly shortened.

[0022] After the repair is completed, the gear surface is subjected to necessary post-processing, such as polishing, cleaning or heat treatment, to restore its original performance. The repaired area is evaluated again using testing equipment to ensure that the repair quality meets the standards.

[0023] In addition, the present invention may also be provided with some auxiliary facilities, which are not shown in the figure, and a protective gas supply system (to prevent oxidation), such as argon, nitrogen, etc., dust removal and exhaust system (to keep the working environment clean), safety shielding (to protect operators from radiation damage), etc., may be arranged around the main working area. Since high-energy beam irradiation will increase the surface temperature of the gear, a cooling system is required to cool the gear to ensure the repair effect and equipment safety. The cooling system may be water-cooled, air-cooled, etc.

[0024] Further, the three-axis moving mechanism includes a support 6, a lifting block 9, a lateral movement block 10, front and rear guide rails, a lifting guide rail and a lateral movement guide rail; The bottom of the support 6 is connected to the base 7 via front and rear guide rails; the side of the support 6 is connected to the lifting block 9 via a lifting guide rail; the lifting block 9 is connected to the lateral block 10 via a lateral guide rail; the working head 5 is fixedly connected to the lateral block 10.

[0025] The front and rear guide rails, lifting guide rails and transverse guide rails are all existing technologies, such as electric guide rails. The working direction of the three is the spatial XYZ direction. Specifically, the front and rear guide rails drive the support 6 to move forward and backward, the lifting guide rails drive the lifting block 9 to move up and down, and the transverse guide rails drive the transverse block 10 and the working head 5 to move left and right, thereby realizing the three-degree-of-freedom movement of the working head 5 in space.

[0026] like Figure 2-Figure 6 , the indexing mechanism 12 includes a motor 121, a spindle 122, a box 125, a driven rod 127 and a cam 128; The motor 121 is mounted on the box 125, the output end of the motor 121 is fixedly connected to the cam 128, the cam 128 is located in the box 125, and the bottom of the driven rod 127 is set in the rotation range of the cam 128; the main shaft 122 is rotatably connected to the box 125, and the bottom of the main shaft 122 and the bottom of the driven rod 127 are both located in the box 125; the top of the main shaft 122 passes through the box 125 and is connected to the gear 2 to be repaired; The cam 128 is used to push the driven rod 127 to rotate around the main shaft 122, so that the main shaft 122 drives the gear 2 to be repaired to rotate at its pitch angle.

[0027] Specifically, the rotation axis of the cam 128 is arranged horizontally, while the driven rod 127 is arranged vertically. The driven rod 127 has no degree of freedom in the vertical direction and cannot be raised or lowered, but in the circumferential direction of the main shaft 122, the driven rod 127 can move around the main shaft 122. When the cam 128 rotates, the protruding portion of the cam 128 periodically contacts the driven rod 127, and the driven rod 127 moves only when the protruding portion contacts the driven rod 127. Therefore, during the rotation of the cam 128, the driven rod 127 moves periodically, and the rotation range of the main shaft 122 driven by the driven rod 127 just makes the repair gear 2 rotate its pitch angle. This matching relationship can be obtained by those skilled in the art through calculation, debugging, etc.

[0028] The bottom of the box body 125 can be fixed on the base 7 through the bracket 11.

[0029] Furthermore, the indexing mechanism 12 also includes a reset assembly, a driven sleeve 130, an elastic push rod 131, a pawl 132 and a driven wheel 133; The driven rod 127 is connected to the box body 125 through the reset assembly, so as to reset the driven rod 127 when it is not in contact with the cam 128; the side surface of the driven rod 127 is fixedly connected to the outer side surface of the driven sleeve 130 through the connecting rod 126; The driven sleeve 130 is sleeved on the main shaft 122, and the driven sleeve 130 is rotatably connected to the box body 125. The inner side surface of the driven sleeve 130 is rotatably connected to one end of the pawl 132, and the other end of the pawl 132 is clamped in the tooth groove of the driven wheel 133. The driven wheel 133 is sleeved on the main shaft 122, and the elastic push rod 131 is installed on the side wall of the driven sleeve 130, and the end of the elastic push rod 131 abuts against the outer side of the pawl 132.

[0030] An annular chamber is separated between the driven sleeve 130 and the driven wheel 133, and the chamber is used to arrange the pawl 132. The main function of the reset assembly is to reset the driven rod 127. After the driven rod 127 is driven by the cam 128, the reset assembly returns the driven rod 127 to the initial position. The function of the elastic push rod 131 is to apply an elastic force to the pawl 132 so that the pawl 132 can be reset.

[0031] Furthermore, the ratchet 132 and the elastic push rod 131 are provided in plurality correspondingly.

[0032] The working principle of the indexing mechanism 12 is: the motor 121 drives the cam 128 to rotate, the protruding part of the cam 128 pushes the driven rod 127 to move around the main shaft 122, the driven rod 127 drives the driven sleeve 130 to rotate through the connecting rod 126, the rotation of the driven sleeve 130 drives the pawl 132 to rotate, and the end of the pawl 132 abuts against the driven wheel 133, thereby rotating the driven wheel 133 and the main shaft 122, so that the gear 2 to be repaired rotates by a pitch angle. When the protruding part of the cam 128 is disengaged from the driven rod 127 during the rotation process, the driven rod 127 is reset by the reset assembly, waiting for the next contact of the cam 128, and the driven rod 127 rotates when it is reset, and drives the driven sleeve 130 to rotate. While the driven sleeve 130 rotates, the pawl 132 rotates in the opposite direction and contacts with the driven wheel 133 to generate vibration, and the elastic push rod 131 abuts against the pawl 132 to keep the pawl 132 in contact with the driven wheel 133, and the pawl 132 cannot drive the driven wheel 133 to rotate during the reverse rotation process. In addition, in order to eliminate the friction between the pawl 132 and the driven wheel 133 during the rotation of the driven sleeve 130, a damping seat 134 can be set at the bottom of the main shaft 122, and the damping seat 134 is rotatably connected to the bottom of the main shaft 122, and the rotation damping is realized through components such as rubber rings, so as to prevent the rotation of the main shaft 122 under a small torque.

[0033] Furthermore, the elastic push rod 131 includes a connecting bolt 1310, a connecting head 1311, an elastic sleeve 1312 and a bendable elastic member 1313; The connecting bolt 1310 is threadedly connected to the side wall of the driven sleeve 130 , and the end of the connecting bolt 1310 is detachably connected to the connecting head 1311 . The end of the connecting head 1311 is connected to the elastic sleeve 1312 . The bendable elastic member 1313 is arranged in the elastic sleeve 1312 , and the end of the elastic sleeve 1312 abuts against the outer side of the pawl 132 .

[0034] A blind hole may be provided at the end of the connecting bolt 1310, one end of the connector 1311 is inserted into the blind hole, and a protrusion may be provided at the other end of the connector 1311. The elastic sleeve 1312 is open at one end and closed at the other end, and its open end is sleeved on the protrusion and can be connected by threads. The elastic sleeve 1312 may be made of rubber, and the bendable elastic member 1313 may be a spring, rubber or other components. During the reverse rotation of the pawl 132, the vibration offset generated by the pawl 132 causes the elastic sleeve 1312 to bend and deform.

[0035] Further, the reset assembly includes an arc-shaped rod 135, an arc-shaped opening 136, an arc-shaped inner hole 129 and an elastic component 123; The top of the box body 125 is provided with the arc-shaped inner hole 129, one end of the arc-shaped inner hole 129 is provided with the arc-shaped opening 136, and the arc-shaped rod 135, the arc-shaped inner hole 129, the driven sleeve 130 and the main shaft 122 are coaxially arranged; One end of the arc rod 135 is arranged in the arc inner hole 129, and the elastic component 123 is arranged in the arc inner hole 129. The elastic component 123 abuts against the arc rod 135. The other end of the arc rod 135 is fixedly connected to the driven rod 127, and the driven rod 127 is located in the arc opening 136.

[0036] The arc opening 136 is an arc-shaped long strip through-hole structure, and the elastic component 123 can be an arc spring. The elastic component 123 applies a squeezing force to the arc rod 135, so that the driven rod 127 abuts against one end of the arc opening 136. This state is the initial state position of the driven rod 127, as shown in FIG. Figure 5 When the driven rod 127 is driven to move by the cam 128, the arc rod 135 moves in the arc inner hole 129 and squeezes the elastic component 123. When the bottom of the driven rod 127 is separated from the protruding part of the cam 128, the elastic component 123 restores its deformation and drives the driven rod 127 to reset.

[0037] In addition, the end of the arc-shaped rod 135 can be fixedly connected to a slider 137 , the slider 137 is adapted to the arc-shaped inner hole 129 , and the slider 137 abuts against the elastic component 123 .

[0038] Furthermore, the top opening of the box body 125 is detachably connected to the double-layer cover plate 124, and the double-layer cover plate 124 includes two plates, and arc grooves are arranged on opposite sides of the two plates, and the two arc grooves are arranged oppositely to form the arc inner hole 129. The purpose of providing the double-layer cover plate 124 is to facilitate the processing of the arc inner hole 129 and to facilitate the assembly of the driven rod 127 and the arc rod 135.

[0039] The repaired area of ​​the repaired gear 2 of the present invention can be manually identified. After the repaired area is manually observed, the working head 5 repairs the repaired area through the combined action of the indexing mechanism 12 and the three-axis moving mechanism. The following method can also be used: A gear repair method based on high-energy beam, wherein a detection and identification module 4 is arranged on a working head 5, and the tooth surface of the gear 2 to be repaired is detected by the detection and identification module 4 to identify the position of wear, cracks or other defects; a multi-spectral industrial camera array is used to scan each tooth surface of the gear 2 to be repaired that is driven by a dividing mechanism 12 to rotate, and image data is collected; and a laser displacement sensor is used to synchronously obtain three-dimensional morphology data; the collected raw data is pre-processed in real time by an edge computing node, and feature extraction is performed through a defect recognition model of a deep convolutional neural network based on a ResNet-50 architecture, which can accurately identify microcracks as small as 0.02 mm, tooth profile deviations of 0.1 mm, and abnormal hardness areas caused by uneven quenching.

[0040] The method specifically includes: Step 1, installing the detection and identification module 4 on the working head 5; Step 2, the indexing mechanism 12 drives the gear 2 to be repaired to rotate, and the detection and recognition module 4 identifies the area to be repaired of the gear 2 to be repaired; Step 3, adjusting the position of the working head 5 by means of the three-axis moving mechanism so that the output ends of the high energy beam generator 3 and the powder feeder 8 face the repaired area of ​​the gear 2 to be repaired; In step 4, the high energy beam generator 3 and the powder feeder 8 work simultaneously to generate a high energy beam and powder onto the area to be repaired, thereby forming a cladding layer to repair the gear.

[0041] Furthermore, the detection and identification module 4 includes a multi-spectral industrial camera array and a laser displacement sensor; In the step 2, when the detection and identification module 4 identifies the area to be repaired of the gear 2 to be repaired, the following steps are included: Step 2.1, establish a multi-camera array geometric projection model: Set up k The transformation matrix from the camera coordinate system to the world coordinate system is ,in is the rotation matrix, is the translation vector; The imaging formula is: , in is the camera intrinsic parameter matrix, and is the pixel coordinate, X w ，Y w ，Z w is the world coordinate; from the camera coordinate system to the image coordinate system, it is a perspective projection relationship, from 3D to 2D. At this time, the unit of the projection point p is still mm, not pixel, and needs to be further converted to the pixel coordinate system. The pixel coordinate system and the image coordinate system are both on the imaging plane, but their origins and measurement units are different. The origin of the image coordinate system is usually the midpoint of the imaging plane, and the unit is mm, which is a physical unit. The unit of the pixel coordinate system is pixel, and we usually describe a pixel point in terms of several rows and columns.

[0042] Step 2.2, multispectral fusion: for each pixel Weighted fusion of spectral intensities in N bands: , Weight Optimize allocation based on defect-sensitive bands, such as near-infrared is sensitive to cracks; Step 2.3, laser 3D profile measurement: The laser line of the laser displacement sensor is projected onto the surface of the gear 2 to be repaired, and the reflected light spot is at the sensor imaging position. With height Relationship: , in, is the baseline distance, is the laser emission angle, is the focal length of the lens; Combined gear rotation angle , convert the 2D laser profile into a 3D point cloud: , in, It is the radial distance, which is obtained synchronously in real time through the encoder; Step 2.4: The raw data collected by the multispectral industrial camera array and laser displacement sensor are preprocessed in real time through the edge computing node, such as noise reduction, enhancement, segmentation, etc. Step 2.5, feature extraction is performed through the defect recognition model based on the deep convolutional neural network of the ResNet-50 architecture. The deep convolutional neural network of the ResNet-50 architecture is characterized by the use of a residual network structure, which has a depth of 50 layers and can effectively alleviate the degradation problem, realize a deeper network structure design, and improve the training accuracy of the network. The composition of the model is as follows: (1) Residual module: It consists of three convolutional layers (1×1 dimensionality reduction, 3×3 feature extraction, and 1×1 dimensionality increase). It implements feature reuse through skip connections, solves the gradient vanishing problem, and improves sensitivity to tiny defects.

[0043] (2) Feature pyramid structure: It consists of a 50-layer deep network (34 residual blocks + 16 transition layers), which realizes multi-scale feature extraction from local texture to global morphology through gradually expanded convolution kernels (7×7→3×3).

[0044] (3) Transfer learning mechanism: Usually fine-tuning is performed based on ImageNet pre-training, and the model is adapted to the defect classification requirements of specific industrial scenarios by replacing the final fully connected layer (such as changing it to a Softmax classification layer).

[0045] (4) Feature fusion module: Some improved models will combine the attention mechanism (such as the SE module) or cascade with the UNET structure to enhance the feature weight of the defect area while retaining the spatial positioning ability.

[0046] The loss function is a key regulator of model performance. Its role is to optimize model performance, enhance the distinction of defect features, and improve accuracy. It directly affects the model's sensitivity to defect features and classification performance. Therefore, for this defect recognition model, a specific loss function is set. This specific loss function is combined with the FocalLoss loss function and the DiceLoss loss function to obtain a total loss function; In addition, the deep convolutional neural network with ResNet-50 architecture usually accepts 224×224 RGB images as input, but gear defects involve higher resolution images, such as 512×512 grayscale images. Therefore, it is necessary to modify the input layer, change the number of channels from 3 to 1, and adjust the subsequent convolutional layer parameters to adapt to the new size.

[0047] In step 2.6, the data of the multispectral industrial camera array and the laser displacement sensor are synchronized in time and aligned in space. Through calibration, the data of each sensor are unified to the same coordinate, and then the Kalman filter formula is used to obtain more accurate coordinates, thereby achieving sub-pixel positioning of the coordinates of the repair area of ​​the gear 2 to be repaired (positioning accuracy reaches 0.01mm).

[0048] The digital twin technology is used to align the detected coordinates with the virtual model, taking into account the conversion of the coordinate system, using rigid body transformation and ICP (iterative closest point) registration algorithm. In this way, the detection results are mapped to the virtual gear model in real time (error ±0.03mm). These data are input into the control system 1 to provide accurate target coordinates for subsequent high-energy beam repair and compare the repaired results with the gear model data, so as to adjust the repair strategy in time and ensure the accuracy of the repaired gear.

[0049] Among them, the rigid body registration adopts the ICP algorithm, which includes the following steps: Minimize the actual point cloud With model point cloud Distance: , Solve the optimal rotation through SVD decomposition (singular value decomposition) and pan .

[0050] Dynamic Error Compensation: Introducing Feedback Control Correct mapping errors: , in, , is the proportional coefficient, which is adjusted by the PID controller.

[0051] The detection and identification module 4 of the present invention may also include temperature and gas sensors for real-time monitoring of parameters such as temperature, molten pool morphology, gas composition, etc. during the repair process, as well as dimensional accuracy and surface quality after repair. This information is fed back to the control system for real-time adjustment of the repair strategy.

[0052] Furthermore, in step 2.5, the FocalLoss loss function is expressed by the following formula: , in, is the modulation factor, Used to adjust the ratio between positive and negative sample losses. , is an adjustable focusing parameter that can adjust the degree of reduction in the weight of easy-to-classify samples. The larger the value, the greater the degree of weight reduction. By adjusting the weight coefficients of difficult and easy samples, the model can be prevented from being biased towards the majority class; The DiceLoss function is expressed by the following formula: , is the value of the i-th pixel predicted by the model, is the value of the i-th pixel of the true label, is the smoothing coefficient; The total loss function is expressed by the following formula: , in, is the proportional factor. In industrial inspection, high precision and robustness are required. Usually, the loss function needs to be designed to be adaptive according to the scene characteristics such as defect morphology (point-shaped or linear defects) and data magnitude (small sample size or large data) to optimize the model performance. The proportional adjustment is used to find a specific loss function suitable for gear surface defects.

[0053] After repeated verification, When , the total loss function has the highest adaptability. The values ​​of the above three parameters are obtained through repeated model training to obtain a loss function that matches the defect recognition task.

[0054] The above-described embodiments are only for describing the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, a person skilled in the art will be able to All kinds of deformation, modification, alteration and substitution made by members to the technical solution of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A new gear repair device based on high energy beam, characterized in that: It comprises a high energy beam generator (3), a working head (5), a base (7), a powder feeder (8), a dividing mechanism (12) and a three-axis moving mechanism; The three-axis moving mechanism is arranged on the base (7), the three-axis moving mechanism is connected to the working head (5), the output ends of the high-energy beam generator (3) and the powder feeder (8) are integrated on the working head (5), the working head (5) faces the gear to be repaired (2), and the working head (5) adjusts its position through the three-axis moving mechanism so that the output ends of the high-energy beam generator (3) and the powder feeder (8) face the area to be repaired of the gear to be repaired (2); The gear to be repaired (2) is mounted on the indexing mechanism (12), and the indexing mechanism (12) is arranged on the base (7). The indexing mechanism (12) is used to drive the gear to be repaired (2) to rotate, and each rotation angle is the pitch angle of the gear to be repaired (2).

2. A novel gear repair device based on high energy beam according to claim 1, characterized in that: The three-axis moving mechanism comprises a support (6), a lifting block (9), a transverse moving block (10), front and rear guide rails, a lifting guide rail and a transverse moving guide rail; The bottom of the support (6) is connected to the base (7) via front and rear guide rails; the side of the support (6) is connected to the lifting block (9) via lifting guide rails; the lifting block (9) is connected to the lateral movement block (10) via lateral movement guide rails; and the lateral movement block (10) is fixedly connected to the working head (5).

3. The novel gear repair device based on high energy beam according to claim 1 is characterized in that: The indexing mechanism (12) comprises a motor (121), a main shaft (122), a housing (125), a driven rod (127) and a cam (128); The motor (121) is mounted on the housing (125); the output end of the motor (121) is fixedly connected to the cam (128); the cam (128) is located in the housing (125); the bottom of the driven rod (127) is arranged within the rotation range of the cam (128); the main shaft (122) is rotatably connected to the housing (125); the bottom of the main shaft (122) and the bottom of the driven rod (127) are both located in the housing (125); the top of the main shaft (122) passes through the housing (125) and is connected to the gear (2) to be repaired; The cam (128) is used to push the driven rod (127) to rotate around the main shaft (122), so that the main shaft (122) drives the gear (2) to be repaired to rotate at the angle of its tooth pitch angle.

4. A novel gear repair device based on high energy beam according to claim 3, characterized in that: The indexing mechanism (12) further comprises a reset assembly, a driven sleeve (130), an elastic push rod (131), a ratchet pawl (132) and a driven wheel (133); The driven rod (127) is connected to the box body (125) via the reset assembly, so as to reset the driven rod (127) when it is not in contact with the cam (128); the side surface of the driven rod (127) is fixedly connected to the outer side surface of the driven sleeve (130) via a connecting rod (126); The driven sleeve (130) is sleeved on the main shaft (122), the driven sleeve (130) is rotatably connected to the box body (125), the inner side surface of the driven sleeve (130) is rotatably connected to one end of the pawl (132), the other end of the pawl (132) is clamped in the tooth groove of the driven wheel (133), the driven wheel (133) is sleeved on the main shaft (122), the elastic push rod (131) is installed on the side wall of the driven sleeve (130), and the end of the elastic push rod (131) abuts against the outer side of the pawl (132).

5. A novel gear repair device based on high energy beam according to claim 4, characterized in that: The elastic push rod (131) comprises a connecting bolt (1310), a connecting head (1311), an elastic sleeve (1312) and a bendable elastic member (1313); The connecting bolt (1310) is threadedly connected to the side wall of the driven sleeve (130); the end of the connecting bolt (1310) is detachably connected to the connecting head (1311); the end of the connecting head (1311) is connected to the elastic sleeve (1312); the bendable elastic member (1313) is arranged inside the elastic sleeve (1312); and the end of the elastic sleeve (1312) abuts against the outer side of the ratchet (132).

6. The novel gear repair device based on high energy beam according to claim 4 is characterized in that: The resetting assembly comprises an arc-shaped rod (135), an arc-shaped opening (136), an arc-shaped inner hole (129), and an elastic component (123); The top of the box body (125) is provided with the arc-shaped inner hole (129), one end of the arc-shaped inner hole (129) is provided with the arc-shaped opening (136), and the arc-shaped rod (135), the arc-shaped inner hole (129), the driven sleeve (130) and the main shaft (122) are coaxially arranged; One end of the arc-shaped rod (135) is arranged in the arc-shaped inner hole (129), the elastic component (123) is arranged in the arc-shaped inner hole (129), the elastic component (123) abuts against the arc-shaped rod (135), and the other end of the arc-shaped rod (135) is fixedly connected to the driven rod (127), and the driven rod (127) is located in the arc-shaped opening (136).

7. A novel gear repair device based on high energy beam according to claim 6, characterized in that: The top opening of the box body (125) is detachably connected to the double-layer cover plate (124), and the double-layer cover plate (124) comprises two plate bodies, and arc-shaped grooves are arranged on opposite sides of the two plate bodies, and the two arc-shaped grooves are arranged opposite to each other to form the arc-shaped inner hole (129).

8. A gear repair method based on high energy beam, characterized in that: A novel gear repair device based on high energy beam as described in any one of claims 1 to 8, the method comprising: Step 1, installing a detection and identification module (4) on a working head (5); Step 2: the indexing mechanism (12) drives the gear to be repaired (2) to rotate, and the detection and recognition module (4) identifies the area to be repaired of the gear to be repaired (2); Step 3, adjusting the position of the working head (5) by means of a three-axis moving mechanism so that the output ends of the high-energy beam generator (3) and the powder feeder (8) face the area to be repaired of the gear (2) to be repaired; In step 4, the high energy beam generator (3) and the powder feeder (8) work simultaneously to generate a high energy beam and powder onto the area to be repaired, thereby forming a cladding layer to repair the gear.

9. The gear repair method based on high energy beam according to claim 8, characterized in that: The detection and identification module (4) includes a multi-spectral industrial camera array and a laser displacement sensor; In the step 2, when the area to be repaired of the gear (2) to be repaired is identified by the detection and identification module (4), the following steps are included: Step 2.1, establish a multi-camera array geometric projection model: Set up k The transformation matrix from the camera coordinate system to the world coordinate system is ,in is the rotation matrix, is the translation vector; The imaging formula is: ， in is the camera intrinsic parameter matrix, and is the pixel coordinate, X w ，Y w ，Z w is the world coordinate; Step 2.2, multispectral fusion: for each pixel Weighted fusion of spectral intensities in N bands: ， Weight Optimize allocation according to defect-sensitive bands; Step 2.3, laser 3D profile measurement: The laser line of the laser displacement sensor is projected onto the surface of the gear to be repaired (2), and the reflected light spot is at the sensor imaging position. With height Relationship: ， in, is the baseline distance, is the laser emission angle, is the focal length of the lens; Combined gear rotation angle , convert the 2D laser profile into a 3D point cloud: ， in, is the radial distance; Step 2.4, the raw data collected by the multispectral industrial camera array and the laser displacement sensor are preprocessed in real time through the edge computing node; Step 2.5, feature extraction is performed through a defect recognition model based on a deep convolutional neural network of the ResNet-50 architecture. For the defect recognition model, a loss function is set. The loss function is combined with the FocalLoss loss function and the DiceLoss loss function to obtain a total loss function. Step 2.6, synchronize the data of the multi-spectral industrial camera array and the laser displacement sensor in time and align them in space. Through calibration, unify the data of each sensor to the same coordinate, and then use the Kalman filter formula to obtain more accurate coordinates, so as to realize the positioning of the coordinates of the repair area of ​​the gear to be repaired (2).

10. A gear repair method based on high energy beam according to claim 9, characterized in that: In step 2.5, the FocalLoss loss function is expressed by the following formula: ， in, is the modulation factor, Used to adjust the ratio between positive and negative sample losses. is an adjustable focus parameter; The DiceLoss function is expressed by the following formula: ， The model predicts The value of pixels, is the true label The value of pixels, is the smoothing coefficient; The total loss function is expressed by the following formula: ， in, ; is the scale factor.

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