Automatic grinding method of steel rail refiner

Abstract

The invention belongs to the field of railway tracks, and particularly relates to an automatic grinding method of a steel rail refiner, which comprises the following steps of: pressing and clamping a steel rail; steel rail scanning; grinding wheel position detection; first-time grinding is conducted, specifically, the cross beam is moved to a designated grinding position, and a grinding head starts grinding work, that is, the grinding head executes reciprocating motion to grind the steel rail; the polishing amount is controlled by sensing the intensity of spark light through a spark sensor; other polishing steps are continuously repeated at each angle until polishing is completed; and step 6, turning back to the original place. Leveling is conducted through laser scanning, the offset parameter and the feeding compensation parameter of the grinding beam in the grinding process are calculated through scanning data, it is ensured that the grinding head is parallel to the steel rail at each working angle, the grinding quality is improved, and steel rail reward is avoided; in the grinding process, compensation of feeding and retracting of the cross beam is conducted through the spark sensor according to the light intensity of different sparks, the grinding quality is guaranteed, and the steel rail is prevented from being damaged or insufficient grinding is avoided.

Description

Technical Field

[0001] This application belongs to the field of railway tracks, and in particular, to an automatic grinding method for rail fine grinders. Background Art

[0002] According to the requirements of "TB / T 1632.2 - 2014 Welding of Rails - Part 2 Flash Welding", after rail welding, external profile finishing and straightness inspection (fine grinding) are required: External profile finishing can be carried out by milling or grinding. During external profile finishing, the base metal of the rail should not be damaged. After fixed flash welding of the rail, obvious weld beads will be generated at the weld. Then, after the treatment with a weld bead pushing tool, a weld bead of 1 - 2 mm will remain at the weld. To ensure the safe and high-speed operation of the train, it is necessary to grind the weld to ensure the smoothness of the weld. Therefore, after pushing the weld bead, first use a rough rail grinder to roughly grind the weld of the rail to ensure that the remaining amount of the weld is less than 0.5 mm. Then, straighten the rail to ensure the parallelism of the rail. Finally, carry out fine grinding. Fine grinding mainly ensures the smoothness and straightness on both sides of the welded joint.

[0003] Currently, most of the equipment used for weld grinding is manually operated, completely relying on the eyesight and experience of the operators, resulting in problems such as low grinding efficiency, unstable effect, and large precision differences. The existing automatic grinding methods usually adopt position mode or ordinary rail profiling grinding. For example, the French Giesma fine grinder uses a spark sensor to detect the position and a rodless cylinder to reciprocate for grinding, with fast response and grinding speed. However, during the grinding process, dust fills the air, and the dust is very easy to enter the rodless cylinder, causing the cylinder seals to be extremely easy to damage. In addition, to ensure the positioning accuracy, the lifting mechanisms at both ends of the crossbeam of the Giesma fine grinder use a similar digital hydraulic cylinder to control the lifting. Such digital hydraulic cylinders belong to precision control components, with high manufacturing cost and are extremely easy to wear and damage when working in a dust environment.

[0004] Domestic grinding equipment all uses wheel pressure sensing to profile grind the rail. The above methods cannot automatically adjust the grinding feed amount according to the actual weld, easily causing problems such as insufficient grinding or damage to the base metal, and unable to ensure the quality of weld grinding. Therefore, it is necessary to study a grinding method that can meet the rail grinding requirements and is applied to automatic rail weld grinding equipment to ensure the high efficiency and high quality standards of rail weld grinding. Summary of the Invention

[0005] In order to solve the problem that the grinding wheel feed amount cannot be changed according to the actual situation during the working process of the existing automatic rail grinding equipment, this application provides an automatic grinding method for rail fine grinders, replacing manual forward and backward feed to correct the grinding amount in order to improve the grinding quality and efficiency and ensure the accuracy of the grinding wheel feed amount.

[0006] To achieve the above technical effects, the specific solution of this application is as follows:

[0007] An automatic grinding method for rail fine grinders includes the following steps:

[0008] Step 1. Rail pressing and clamping: The rail is transported to the fine grinder equipment through a conveyor line, aligning the rail weld with the weld center scale, and then the rail is centered and clamped and the two ends are pressed and positioned.

[0009] Step 2. Rail scanning: The laser sensor on the grinding transverse movement device scans the heights at both ends of the rail grinding section, calculates the rail slope, and automatically levels it to a specified height through the servo motors at both ends of the crossbeam device so that the crossbeam is parallel to the rail, that is, the grinding transverse movement device and the grinding wheel on the crossbeam are parallel to the rail.

[0010] Step 3. Grinding wheel probing: The crossbeam descends to drive the grinding transverse movement device to descend, and the grinding wheel approaches the rail. The working surface of the grinding wheel for grinding is the grinding head. The grinding head approaches the rail and contacts the rail to complete precise probing, and at the same time, the dust removal device starts. The precise probing obtains the position of the crossbeam when the grinding head contacts the rail through the feedback of the current generated by the servo driver after the grinding head contacts the rail.

[0011] Step 4. First-pass grinding: Move the crossbeam to the specified grinding position, and the grinding head starts grinding work, that is, the grinding head performs a reciprocating motion to grind the rail. During the reciprocating automatic grinding process, every 2 reciprocations, the crossbeam descends 0.2 mm, and the grinding amount of the grinding head is 0.2 mm. The grinding amount is controlled by sensing the intensity of the spark light through a spark sensor.

[0012] Step 5. Other-pass grinding: After grinding one angle, the crossbeam rises to lift the grinding head, and the swing arm lifting device performs an angle flip, with the flip range being 0° - 180°. Steps 4 and 5 are continuously repeated for each angle until grinding is completed.

[0013] Step 6. Flip back to the original: After grinding is completed, the crossbeam drives the grinding transverse movement device to rise to a safe position (no interference with the rail during the flipping process), the swing arm lifting device flips to 90°, and the rail is released from the centered clamping and the two-end pressing state.

[0014] Further, in Step 1, first, the rail is transported to the fine grinding station through the support rollers and the rail guiding frame, then the weld center scale is aligned with the rail weld by controlling the moving trolley, and then the rail clamping device and the rail pressing device are used to clamp and press the rail. The rail locking device mainly applies pressure through a hydraulic pump station to the pressure head.

[0015] Further, in step 2, the laser sensors on the grinding transverse movement device are used to scan the rail head, working edge, and non-working edge of the rail respectively. The slope is calculated based on the height data and height difference of the two ends of the grinding section of the rail obtained by scanning, and the offset and compensation amount of the crossbeam at each process angle are calculated based on the current angular position of the crossbeam. The leveling is to adjust the grinding head to be parallel to the rail, which is convenient for full grinding and avoids damaging the rail.

[0016] Furthermore, the positions of the two ends of the grinding section of the rail are X1 and X2 respectively. The height data of X1 is Y1, and the height data of X2 is Y2. The height difference ΔY = Y2 - Y1. The specific calculation method of the slope K is: where ΔX = X2 - X1. The calculation method of the offset ΔL is: ΔL = ΔY * sinα + ΔX * cos(α - 2.86°). The initial flipping angle of the process is 2.86°, α is the real-time angle of the process, and the compensation amount Δl = -ΔL.

[0017] Further, in step 3, when detecting the position, the crossbeam descends. After the grinding head contacts the rail, the relative position of the crossbeam when the grinding head contacts the rail is obtained through the current feedback of the grinding wheel motor. After the position detection is completed, the crossbeam is lifted by a set height to adjust the working position of the grinding head.

[0018] Furthermore, the set height for the crossbeam to be lifted upward is set to 0.4 mm, and the height of the weld bead in the fine grinding stage is 0.4 mm. During the reciprocating grinding process, the weld bead is gradually ground off.

[0019] Further, in step 3, the dust removal device adopts an imported central dust purification system. The air volume of the whole system is 4000 m 3 / h, the total pressure of the fan is 3200 Pa, the filtration area is 30 m2, and the filtration accuracy is less than 0.1 um.

[0020] Further, in step 4, the reciprocating grinding of the grinding head is realized through the grinding transverse movement device. The range of the grinding working section is controlled by a reciprocating servo motor. The center scale of the weld is the center of the working section, that is, the weld is always at the center of the grinding working section. The range of the grinding working section is set between 300 mm and 400 mm.

[0021] Further, in step 4, during the grinding process, a spark sensor is equipped on the grinding transverse movement device. When the spark intensity generated during the grinding process in the non-weld bead section is greater than 2000 Lux, the PLC controls the crossbeam to execute a retraction command through servo control, and the retraction amount is 0.1 mm. When the spark intensity generated during the grinding process in the weld bead section is less than 1000 Lux, the PLC controls the crossbeam to execute an advancement command through servo control, and the advancement amount is 0.1 mm, so as to control the grinding amount.

[0022] Furthermore, before flipping to the next working angle in Step 5, the crossbeam needs to rise by at least 5 mm to avoid interference and collision with the rail during the flipping process.

[0023] Furthermore, in Step 5, before grinding at each angle, the crossbeam is leveled first, and then reciprocating grinding is carried out. The height of the crossbeam of other tracks = the height of the previous crossbeam + the corresponding probing data. The grinding process of other tracks is repeated until the grinding of all angles is completed. The corresponding probing data means that before grinding, the rail is probed and profiled at each grinding angle of the set process by the grinding head, and the absolute displacement value X of the crossbeam when the grinding head touches the surface of the rail at each angle is obtained. n , and the relative displacement value ΔX required for moving the grinding crossbeam corresponding to the previous grinding angle is calculated, where ΔX = X n+1 -X n .

[0024] The above solution of the present invention has the following advantages compared with the existing technology:

[0025] 1. The automatic grinding method designed by the present invention levels by laser scanning, and calculates the offset parameter and feed compensation parameter of the grinding crossbeam during the grinding process through the scanned data, ensuring that the grinding head is parallel to the rail at each working angle, improving the grinding quality and avoiding damaging the rail; before grinding, the rail is probed, and the working height of the grinding wheel during grinding is determined according to the probing data. During the execution of the automatic grinding process, after the first probing, the crossbeam of the subsequent angle automatically moves to the corresponding height to ensure that the grinding head accurately grinds the weld bead; during the grinding process, through the spark sensor, according to the light intensity of different sparks, the feed and retraction of the crossbeam are compensated to ensure the grinding quality and avoid damaging the rail or insufficient grinding.

[0026] 2. This method adds a spark sensor to participate in the control on the basis of the ordinary grinding scheme, and performs automatic compensation through the sensor to replace the old scheme of manually inputting the grinding feed compensation, further improving the automation degree of the equipment.

[0027] 3. By adopting the above weld grinding method, the working height of the grinding head and the feed amount of each grinding angle can be accurately calculated to ensure effective weld grinding and improve the weld grinding quality. Description of the Drawings

[0028] Figure 1 is the process flow chart of the automatic grinding equipment of the precision grinder of the present invention;

[0029] Figure 2 is the three-dimensional view of the automatic grinding equipment of the precision grinder of the present invention.

[0030] In the drawings:

[0031] 1 - Mobile trolley, 2 - Tipping base device, 3 - Tipping swing arm lifting device, 4 - Clamping mechanism, 5 - Weld center scale, 6 - Grinding transverse movement device, 7 - Cross beam device, 8 - Dust collection box, 9 - Support roller, 10 - Rail guide frame, 11 - Rail pressing device, 12 - Connecting shaft, 13 - Dust removal pipeline, 14 - Hydraulic pump station, 15 - Electrical control cabinet. Detailed implementation manners

[0032] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. The components of the embodiments of the present application usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application claimed, but merely represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the scope of protection of the present application.

[0034] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0035] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "upper", "vertical", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship when the product of this application is normally placed, or the orientation or positional relationship commonly understood by those skilled in the art. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application. In addition, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0036] In the description of the present application, it should also be noted that unless otherwise clearly specified and limited, the terms "set", "installed", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0037] Example 1

[0038] An automatic grinding method for rail finishing machines includes the following steps:

[0039] Step 1. Rail pressing and clamping: The rail is conveyed to the finishing machine equipment through a conveyor line, aligning the rail weld with the weld center scale 5, and performing centering clamping and end pressing positioning on the rail;

[0040] Step 2. Rail scanning: The laser sensor on the grinding transverse movement device 6 scans the heights at both ends of the rail grinding section, calculates the rail slope, and automatically levels it to a specified height through the servo motors at both ends of the crossbeam device 7 to make the crossbeam parallel to the rail, that is, the grinding transverse movement device 6 and the grinding wheel on the crossbeam are parallel to the rail;

[0041] Step 3. Grinding wheel probing: The crossbeam descends to drive the grinding transverse movement device 6 to descend, and the grinding wheel approaches the rail. The working surface of the grinding wheel for grinding is the grinding head. The grinding head approaches the rail and contacts the rail to complete precise probing, and at the same time, the dust removal device starts; the precise probing obtains the position of the crossbeam when the rail contacts the grinding head through the feedback of the current generated by the servo driver after the grinding head contacts the rail;

[0042] Step 4. First-pass grinding: Move the crossbeam to the specified grinding position, and the grinding head starts grinding work, that is, the grinding head performs a reciprocating motion to grind the rail; during the reciprocating automatic grinding process, every 2 reciprocations, the crossbeam descends by 0.2 mm, and the grinding amount of the grinding head is 0.2 mm; the grinding amount is controlled by sensing the intensity of the spark light through a spark sensor;

[0043] Step 5. Other-pass grinding: After grinding one angle, the crossbeam rises to lift the grinding head, and the flipping swing arm lifting device 3 performs an angle flip, with the flipping range being 0° - 180°, and flips to the specified angle according to the set process. Steps 4 and 5 are continuously repeated for each angle until the grinding is completed;

[0044] Step 6. Flip back to the original: After the grinding is completed, the crossbeam drives the grinding transverse movement device 6 to rise to a safe position, and the flipping process will not interfere with the rail. The flipping swing arm lifting device 3 flips to 90°, and the rail is released from the centering clamping and end pressing states.

[0045] The automatic grinding method designed by the present invention levels through laser scanning, and calculates the offset parameter and feed compensation parameter of the grinding cross beam during the grinding process based on the scanned data, ensuring that the grinding head is parallel to the rail at each working angle, improving the grinding quality and avoiding damaging the rail; before grinding, the rail is probed, and the working height of the grinding wheel during grinding is determined according to the probing data. During the execution of the automatic grinding process, after the first probing, the cross beam automatically moves to the corresponding height at subsequent angles, ensuring that the grinding head accurately grinds the weld bead; during the grinding process, through the spark sensor, according to the light intensity of different sparks, the compensation for the advancement and retraction of the cross beam is carried out to ensure the grinding quality and avoid damaging the rail or insufficient grinding.

[0046] Embodiment 2

[0047] As Figure 1 shown, an automatic grinding method for a rail precision grinder includes the following steps:

[0048] Step 1. Rail clamping: The rail is transported to the precision grinder equipment through the conveyor line, aligning the rail weld with the weld center scale 5, and performing centering clamping and end pressing positioning on the rail;

[0049] Step 2. Rail scanning: The laser sensor on the grinding transverse movement device 6 scans the heights at both ends of the rail grinding section, calculates the rail slope, and automatically levels the cross beam to the specified height through the servo motors at both ends of the cross beam device 7 to make the cross beam parallel to the rail, that is, the grinding transverse movement device 6 and the grinding wheel on the cross beam are parallel to the rail;

[0050] Step 3. Grinding wheel probing: The cross beam descends to drive the grinding transverse movement device 6 to descend, and the grinding wheel approaches the rail. The working surface of the grinding wheel for grinding is the grinding head. The grinding head approaches the rail and contacts the rail to complete accurate probing, and at the same time, the dust removal device is started; the accurate probing obtains the position of the cross beam when the rail contacts the grinding head through the feedback of the current generated by the servo driver after the grinding head contacts the rail;

[0051] Step 4. First-pass grinding: Move the cross beam to the specified grinding position, and the grinding head starts grinding work, that is, the grinding head performs a reciprocating motion to grind the rail; during the reciprocating automatic grinding process, every 2 reciprocations, the cross beam descends 0.2 mm, and the grinding amount of the grinding head is 0.2 mm; the grinding amount is controlled by sensing the intensity of the spark light through the spark sensor;

[0052] Step 5. Other-pass grinding: After grinding one angle, the cross beam rises, lifting the grinding head, and the swing arm lifting device 3 performs an angle flip, with the flip range being 0° - 180°, and flips to the specified angle according to the set process. Steps 4 and 5 are continuously repeated for each angle until the grinding is completed;

[0053] Step 6. Flip back to the original: After the grinding is completed, the cross beam drives the grinding transverse movement device 6 to rise to a safe position. During the flipping process, there will be no interference with the rail. The flipping swing arm lifting device 3 flips to 90°, and the rail releases the centering clamping and the end pressing states.

[0054] In Step 1, first, the rail is transported to the fine grinding station through the support rollers 9 and the rail guiding frame 10. Then, the weld center scale 5 is aligned with the rail weld by controlling the moving trolley 1. Next, the rail clamping device and the rail pressing device 11 are used to clamp and press the rail. The rail locking device mainly provides pressure through the hydraulic pump station 14 and applies it to components such as the pressure head to achieve locking, which can effectively reduce the vibration generated during the high-speed grinding of the grinding motor, thereby improving the stability and quality of grinding. The weld center scale 5 is mainly used for manual observation of the weld position, facilitating the operator to adjust the weld to the center of the automatic grinding stroke.

[0055] In Step 2, the laser sensors on the grinding transverse movement device 6 scan the rail head, the working edge, and the non-working edge of the rail respectively. The slope is calculated based on the height data and the height difference of the two ends of the grinding section of the rail obtained from the scan. And the offset and compensation amount of the cross beam at each process angle are calculated according to the current angle position of the cross beam. The leveling is to adjust the grinding head to be parallel to the rail, ensuring that during the automatic grinding process, the grinding head and the rail are in a horizontal state, ensuring the smoothness and efficiency of the weld grinding, and facilitating full grinding to avoid damaging the rail.

[0056] Furthermore, the positions of the two ends of the grinding section of the rail are X1 and X2 respectively. Among them, the height data of X1 is Y1, and the height data of X2 is Y2. The height difference ΔY = Y2 - Y1. The specific calculation method of the slope K is: Where ΔX = X2 - X1, the calculation method of the offset ΔL is: ΔL = ΔY * sinα + ΔX * cos(α - 2.86°). From the geometric relationship, the initial flipping angle of the process is 2.86°, α is the real-time angle of the process, and the compensation amount Δl = -ΔL.

[0057] In Step 3, during the position detection, the cross beam descends. After the grinding head contacts the rail, the relative position of the cross beam when the grinding head contacts the rail is obtained through the current feedback of the grinding wheel motor. After the position detection is completed, the cross beam is lifted upward by a set height to adjust the working position of the grinding head, completing the rapid positioning of the working height and the grinding preparation. The descent of the cross beam is controlled by one servo motor at each of the left and right ends through the connecting shaft 12.

[0058] The set height for the cross beam to be lifted upward is generally set to 0.4 mm, that is, the working position of the grinding head is 0.4 mm higher than the rail. And the height of the weld tumor in the fine grinding stage is 0.4 mm. During the reciprocating grinding process, the weld tumor is gradually ground off.

[0059] In Step 3, the dust removal device adopts an imported central dust purification system. The air volume of the whole system is 4000m 3 / h, the total pressure of the fan is 3200Pa, the filtration area is 30m2, and the filtration accuracy is less than 0.1um, meeting the indoor emission standards. According to the dust characteristics generated by the grinding machine, following the principle of capturing the nearest to the dust point of grinding, a reasonable dust capture position and a dust capture and dust removal pipeline 13 are designed, and the pipeline is connected to the main engine of the dust removal system, and finally the dust is collected into the dust collection box 8.

[0060] In Step 4, the reciprocating grinding of the grinding head is realized by the grinding transverse movement device 6. The range of the grinding working section is controlled by the reciprocating servo motor. The weld center scale 5 is the center of the working section, that is, the weld is always at the center of the grinding working section. Since the automatic grinding equipment needs to run on the track and realizes grinding during the running process, a certain operation interval and operation preparation interval need to be reserved on the track. Usually, the range of the grinding working section is set at about 300mm - 400mm.

[0061] In Step 4, during the grinding process, a spark sensor is equipped on the grinding transverse movement device 6. When the spark intensity generated during the grinding process is greater than 2000Lux due to excessive feed rate in the non-weld tumor section, a tool withdrawal compensation command will be triggered. After the PLC in the electrical control cabinet 15 obtains the tool withdrawal compensation signal, it executes the tool withdrawal command through the servo control crossbeam, and the tool withdrawal amount is 0.1mm; when the spark intensity generated during the grinding process is less than 1000Lux due to too small feed rate in the weld tumor section, a feed compensation command will be triggered. After the PLC obtains the feed compensation signal, it executes the feed command through the servo control crossbeam, and the feed amount is 0.1mm, so as to control the grinding amount.

[0062] In Step 5, before flipping to the next working angle, the crossbeam needs to rise at least 5mm to avoid interference and collision with the rail during the flipping process.

[0063] In Step 5, before grinding at each angle, the crossbeam is first leveled, and then reciprocating grinding is carried out. The height of the crossbeam of other passes = the height of the previous pass + the corresponding probing data. Repeat the grinding process of other passes until all angles are ground. The corresponding probing data is that before grinding, the grinding head is used to perform rail probing and profiling for each grinding angle of the set process, and the absolute displacement value X of the crossbeam when the grinding head contacts the rail surface at each angle is obtained n , and the relative displacement value ΔX that the grinding crossbeam needs to move corresponding to the previous grinding angle is calculated, where ΔX = X n+1 -X n .

[0064] The flipping swing arm lifting device 3 mainly consists of components such as a flipping arm, a motor fixing base, a bracket, a high-precision ball screw nut assembly, a servo motor, and a reducer; the flipping base is borne by the flipping base device 2, and the structure of the reverse base device is firm and stable, ensuring the stability of the flipping action. The flipping realizes the precise control of the up and down lifting of the grinding crossbeam, and the left and right ends of the crossbeam are automatically lifted and adjusted, so that the working surface of the grinding wheel is parallel to the rail grinding surface at 0° - 180°.

[0065] The automatic grinding method designed by the present invention levels through laser scanning, and calculates the offset parameter and feed compensation parameter of the grinding crossbeam during the grinding process based on the scanned data, ensuring that the grinding head is parallel to the rail at each working angle, improving the grinding quality, and avoiding damaging the rail; before grinding, the rail is probed, and the working height of the grinding wheel during grinding is determined according to the probing data. During the execution of the automatic grinding process, after the first probing, the crossbeam automatically moves to the corresponding height at subsequent angles, ensuring that the grinding head accurately grinds the weld bead; during the grinding process, through the spark sensor, according to the light intensity of different sparks, the feed and retraction of the crossbeam are compensated to ensure the grinding quality and avoid damaging the rail or insufficient grinding.

[0066] This method adds a spark sensor to participate in the control on the basis of the ordinary grinding scheme, and performs automatic compensation through the sensor, which is used to replace the obsolete scheme of manually inputting the grinding feed compensation, further improving the automation degree of the equipment.

[0067] Adopting the above weld grinding method can accurately calculate the working height of the grinding head and the feed amount of each grinding angle, ensure effective weld grinding, and improve the weld grinding quality.

[0068] Embodiment 3

[0069] Combined with Figure 1 、 Figure 2 As shown, the automatic grinding method of the present invention follows the following process:

[0070] Ⅰ. The rail is pressed and clamped tightly. The rail clamping and centering positioning device 4 is adopted. The rail clamping and centering positioning device mainly consists of components such as a bracket, a roller, a gear clamping arm, and a hydraulic cylinder, and can realize the automatic clamping and centering of the rails at both ends of the weld. The two-side rail pressing devices 11, the air cylinders extend to press the rails tightly. After the centering clamping and pressing, it is convenient to use the laser sensor for scanning.

[0071] II. Rail Scanning. By flipping the swing arm lifting device 3, the grinding wheel working surface grinding head is adjusted to the non-working side. Through laser sensor scanning, the slope data of the rail is obtained by scanning and the grinding head is leveled, that is, the grinding head is parallel to the rail. Similarly, it is flipped to the rail top and the working side respectively for laser scanning, and the returned data is recorded. The crossbeam deflection parameter and the feed compensation parameter during the grinding process are obtained through algorithms, ensuring that the grinding head and the rail are in a horizontal state during the automatic grinding process, and ensuring the smoothness and efficiency of the weld grinding.

[0072] III. Grinding Wheel Position Detection. When the crossbeam descends and the grinding head contacts the rail base metal, the absolute position of the crossbeam when the grinding head contacts the rail can be obtained through the current feedback of the grinding wheel motor. Then, according to the set retraction displacement, the working position of the grinding head is automatically adjusted to complete the rapid positioning and grinding of the weld bead.

[0073] IV. First-pass Grinding. After position detection, reciprocating grinding is performed on the first pass. After grinding a specified number of times, the first-pass grinding is completed. After grinding, the tool is retracted, and then it is flipped to other passes. The grinding head needs to retract at least 5 mm to avoid interference with the base metal during the flipping process.

[0074] V. Other-pass Grinding. First, the crossbeam is leveled, and then grinding feed is performed. The working height of the grinding head at the remaining angles is determined by the relative displacement value ΔX, where ΔX = X n+1 -X n . The other-pass grinding process is repeated until all angles are ground. Grinding according to the above method is only a theoretically uniform weld. To prevent insufficient grinding or damage to the rail caused by rail misalignment, the method of the present invention also adds a spark sensor. During the grinding process, the spark sensor can be used to obtain the light intensity of the spark to judge and execute the feed and retraction commands, complete the feed and retraction compensation of the grinding wheel, and avoid problems such as damage to the base metal caused by excessive feed or insufficient grinding caused by too small feed.

[0075] VI. After all passes are ground, the crossbeam is flipped back to the origin to end the grinding.

[0076] The above is the automatic grinding method of the precision grinder of the present invention. Through this method, the grinding of the weld bead after fixed flash welding can be realized. The method of the present invention first performs centering and profiling on the rail through sensors, and then adds an automatic spark compensation function during the automatic grinding process, significantly improving the quality of weld grinding.

[0077] The preferred embodiments of the present application are described in detail above in conjunction with the accompanying drawings. However, the present application is not limited to the above embodiments, and various changes can be made within the knowledge scope of those of ordinary skill in the art. These changes all fall within the protection scope of the present application.

Claims

1. An automatic grinding method for rail fine grinders, characterized in that, It includes the following steps: Step 1. Rail pressing and clamping: The rail is conveyed to the precision grinding machine equipment through the conveyor line, aligning the rail weld with the weld center scale (5), and performing centering clamping and end pressing positioning on the rail; Step 2. Rail scanning: The laser sensor on the grinding transverse movement device (6) scans the heights at both ends of the rail grinding section, calculates the rail slope, and automatically levels it to the specified height through the servo motors at both ends of the crossbeam device (7) to make the crossbeam parallel to the rail, that is, the grinding transverse movement device (6) and the grinding wheel on the crossbeam are parallel to the rail; Step 3. Grinding wheel probing: The crossbeam descends to drive the grinding transverse movement device (6) to descend, and the grinding wheel approaches the rail. The working surface of the grinding wheel for grinding is the grinding head. The grinding head approaches the rail and contacts the rail to complete precise probing, and at the same time, the dust removal device is started; the precise probing obtains the position of the crossbeam when the grinding head contacts the rail through the feedback of the current generated by the servo driver when the grinding head contacts the rail; Step 4. First-pass grinding: Move the crossbeam to the specified grinding position, and the grinding head starts grinding work, that is, the grinding head performs a reciprocating motion to grind the rail; during the reciprocating automatic grinding process, every 2 reciprocations, the crossbeam descends 0.2 mm, and the grinding amount of the grinding head is 0.2 mm; the grinding amount is controlled by the spark sensor sensing the intensity of the spark light; Step 5. Grinding of other passes: After grinding one angle, the crossbeam rises to lift the grinding head, and the swing arm lifting device (3) performs an angular flip, with the flip range being 0° - 180°. Steps 4 and 5 are continuously repeated for each angle until grinding is completed; Step 6. Flip back to the original: After grinding is completed, the crossbeam drives the grinding transverse movement device (6) to rise to a safe position, the swing arm lifting device (3) flips to 90°, and the rail is released from the centering clamping and end pressing states.

2. The automatic grinding method of a rail precision grinder according to claim 1, characterized in that, In step 4 during the grinding process, a spark sensor is equipped on the grinding transverse movement device (6). When the intensity of the spark light generated during grinding in the non-weld tumor section is greater than 2000 Lux, the PLC controls the crossbeam to execute a retraction command through servo control, and the retraction amount is 0.1 mm; when the intensity of the spark light generated during grinding in the weld tumor section is less than 1000 Lux, the PLC controls the crossbeam to execute an advancement command through servo control, and the advancement amount is 0.1 mm, thereby controlling the grinding amount.

3. The automatic grinding method of a rail precision grinder according to claim 1, characterized in that, In step 1, first, the rail is transported to the precision grinding station through the support rollers (9) and the rail guiding frame (10), then the weld center scale (5) is aligned with the rail weld by controlling the moving trolley (1), and then the rail clamping device and the rail pressing device (11) are used to clamp and press the rail. The rail locking device mainly applies pressure through the hydraulic pump station (14) on the pressure head.

4. The automatic grinding method of a rail precision grinder according to claim 1, characterized in that, In step 2, the laser sensor on the grinding transverse movement device (6) scans the rail top, the working edge, and the non-working edge of the rail respectively. The slope is calculated based on the height data and the height difference of the positions at both ends of the grinding section of the rail obtained by scanning, and the offset amount and compensation amount of the crossbeam at each process angle are calculated according to the current angular position of the crossbeam. The leveling is to adjust the grinding head to be parallel to the rail to facilitate full grinding and avoid damaging the rail.

5. The automatic grinding method of a rail precision grinder according to claim 4, characterized in that, The positions of both ends of the rail in the grinding section are X1 and X2 respectively. Among them, the height data of X1 is Y1, and the height data of X2 is Y2. The height difference ΔY = Y2 - Y1. The specific calculation method of the slope K is as follows: Where ΔX = X2 - X1, the calculation method of the offset ΔL is: ΔL = ΔY * sinα + ΔX * cos(α - 2.86°). The initial flipping angle of the process is 2.86°, α is the real-time angle of the process, and the compensation amount Δl = -ΔL.

6. The automatic grinding method of a rail precision grinder according to claim 1, characterized in that In step 3, during the probing process, the crossbeam descends. After the grinding head contacts the rail, the relative position of the crossbeam when the grinding head contacts the rail is obtained through the current feedback of the grinding wheel motor. After the probing is completed, the crossbeam is lifted upward by a set height to adjust the working position of the grinding head.

7. An automatic grinding method for a rail precision grinder according to claim 6, characterized in that The set height for the crossbeam to be lifted upward is set to 0.4 mm, and the height of the weld bead in the fine grinding stage is 0.4 mm. During the reciprocating grinding process, the weld bead is gradually ground off.

8. The automatic grinding method of a rail precision grinder according to claim 1, characterized in that, In Step 3, the dust removal device uses an imported central dust purification system. The air volume of the whole system is 4000m 3 / h, the total pressure of the fan is 3200 Pa, the filtration area is 30m 2 , and the filtration accuracy is less than 0.1 um.

9. The automatic grinding method of a rail precision grinder according to claim 1, characterized in that In step 4, the reciprocating grinding of the grinding head is realized by the grinding transverse movement device (6). The range of the grinding working section is controlled by the reciprocating servo motor. The weld center scale (5) is the center of the working section, that is, the weld is always at the center of the grinding working section. The range of the grinding working section is set between 300 mm and 400 mm.

10. The automatic grinding method of a rail fine grinder according to claim 1, characterized in that, Before flipping to the next working angle in Step 5, the crossbeam needs to rise by at least 5 mm to avoid interference and collision with the rail during the flipping process. In Step 5, before grinding at each angle, level the crossbeam first, and then perform reciprocating grinding. The height of the crossbeam in other passes = the height of the crossbeam in the previous pass + the corresponding probing data. Repeat the grinding process in other passes until the grinding of all angles is completed. The corresponding probing data means that before grinding, the rail is probed and profiled by the grinding head at each grinding angle of the set process, and the absolute displacement value X of the crossbeam when the grinding head contacts the rail surface at each angle is obtained. n , and calculate the relative displacement value ΔX required for moving the grinding crossbeam corresponding to the previous grinding angle, where ΔX = X n+1 - X n .

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