Knife sharpening robot and grinding track determining method thereof

Abstract

The invention discloses a knife sharpening robot and a grinding track determining method thereof, and relates to the technical field of intelligent robots. The knife sharpening robot comprises a fixing mechanism, a grinding wheel, a driving mechanism, a follow-up adaptation mechanism and a detection mechanism, wherein the fixing mechanism is used for fixing a knife; the working surface of the grinding wheel is opposite to the blade of the cutter; the driving mechanism is used for driving the grinding wheel to reciprocate in the extending direction of the blade. The follow-up adaptation mechanism is connected between the driving mechanism and the grinding wheel and used for driving the grinding wheel to stretch out and draw back in the extending direction perpendicular to the cutting edge when the grinding wheel moves so that the working face can make contact with the cutting edge; the detection mechanism is used for detecting the cutter handle end position and the cutter tip end position of the cutting edge in the moving process of the grinding wheel. According to the knife sharpening robot, through dynamic telescopic compensation, it is ensured that the contact pressure of a grinding wheel to all points of a knife edge is kept basically constant; full-length uniform grinding is achieved, and uniformity and sharpness consistency of the cutting edge are improved.

Description

Technical Field

[0001] This invention relates to the field of intelligent robot technology, and in particular to a grinding robot and a method for determining its grinding trajectory. Background Technology

[0002] The sharpness of a knife directly determines its performance and efficiency. Traditional professional knife sharpening equipment is complex, bulky, and expensive, mainly used in industrial fields. However, to meet the maintenance needs of everyday and kitchen knives, various handheld, simple knife sharpening robots are widely available on the market.

[0003] However, while these knife-grinding robots offer convenience, they suffer from fundamental technical flaws, making it difficult to achieve precise, uniform, and efficient grinding results. Key parameters in the grinding process rely heavily on human experience and operation. Controlling the grinding angle depends entirely on the stability of the user's handheld grip, and determining the grinding range typically relies on visual estimation. This manual judgment method is inefficient and highly susceptible to subjective factors, easily leading to inconsistencies in the starting and ending points of different grinding passes, making it impossible to achieve standardization and repeatability of the grinding range. Existing handheld or simple electric knife-grinding robots usually assume the cutting edge is an ideal straight line and lack the ability to detect the actual curvature or position of the cutting edge in real time. When the tool itself has a slight bend or is installed with a slight tilt, grinding along a fixed path can result in uneven grinding pressure, localized over-grinding or under-grinding, severely affecting the uniformity and consistency of the cutting edge's sharpness. Summary of the Invention

[0004] The purpose of this invention is to provide a grinding robot and a method for determining its grinding trajectory, so as to automatically identify the effective grinding range of the tool and perform precise grinding by adapting to the shape of the cutting edge.

[0005] To achieve this objective, the present invention adopts the following technical solution: A knife-sharpening robot, comprising: A fixing mechanism is used to fix the cutting tool. A grinding wheel, wherein the working surface of the grinding wheel is positioned opposite to the cutting edge of the cutting tool; A drive mechanism is used to drive the grinding wheel to reciprocate along the extension direction of the cutting edge; A follow-up adapter mechanism is connected between the drive mechanism and the grinding wheel, and is used to drive the grinding wheel to extend and retract in a direction perpendicular to the cutting edge when the grinding wheel moves, so that the working surface keeps in contact with the cutting edge; The detection mechanism is used to detect the position of the shank end and the tip of the cutting edge during the movement of the grinding wheel.

[0006] As an optional embodiment of the knife-sharpening robot, the detection mechanism includes a photoelectric sensor, which includes a light source emitter and a light source receiver. The light source emitter and the light source receiver are disposed opposite to each other on both sides of the blade to generate a trigger signal when the blade enters or leaves the detection area.

[0007] As an alternative to the aforementioned knife-grinding robot, the detection plane of the detection mechanism is closer to the fixed mechanism relative to the working surface.

[0008] As an optional solution for the aforementioned knife-sharpening robot, the follow-up adaptation mechanism includes: A bracket for mounting the grinding wheel; A telescopic drive assembly, connected to the bracket, is used to provide power for the telescopic extension and retraction of the grinding wheel; An elastic preload element is disposed between the telescopic drive assembly and the bracket to provide a continuous preload force to the grinding wheel pressing against the cutting edge.

[0009] As an optional embodiment of the knife-sharpening robot, the telescopic drive assembly includes a first motor, a first lead screw, and a telescopic arm. The first motor is connected to the first lead screw and is used to drive the first lead screw to rotate. The first lead screw is connected to the telescopic arm in a transmission connection, and the telescopic arm is fixedly connected to the bracket.

[0010] As an optional feature of the knife-sharpening robot, the detection mechanism is mounted on the support.

[0011] As an optional embodiment of the knife-sharpening robot, the drive mechanism includes a second motor, a second lead screw, and a slide. The second motor is connected to the second lead screw and is used to drive the second lead screw to rotate. The second lead screw is connected to the slide in a transmission manner, and the follower-adapter mechanism is disposed on the slide.

[0012] As an optional embodiment of the knife-sharpening robot, a guide assembly is also included, which includes guide rails arranged parallel to both sides of the second lead screw, and the slide block is slidably connected to the guide rails.

[0013] As an optional embodiment of the knife-sharpening robot, a control unit is also included. This control unit is electrically connected to the drive mechanism, the follow-up adaptation mechanism, and the detection mechanism, and is configured to: The endpoint coordinates of the blade are determined based on the signal from the detection mechanism; The drive mechanism and the follower mechanism are controlled to work together according to the endpoint coordinates, so that the grinding wheel moves along the fitted cutting edge trajectory.

[0014] A method for determining the grinding trajectory of a tool-grinding robot, applied to a tool-grinding robot as described in any of the above embodiments, the method comprising: A coordinate system is established by fixing the cutting tool to the fixing mechanism, using the direction of the reciprocating movement of the grinding wheel driven by the driving mechanism as the X-axis, and using the direction of the extension and retraction of the grinding wheel driven by the follower-adapter mechanism as the Y-axis. The drive mechanism is controlled to move the grinding wheel, and the follow-up adapter is controlled to extend and retract the grinding wheel. The detection mechanism is used to detect the shank end and the tip of the cutting edge, and the coordinates of the shank end and the tip of the cutting edge are recorded to determine the grinding range. Within the grinding range, the grinding wheel is controlled to move along the X-axis, and the amount of extension and retraction in the Y-axis direction of the grinding wheel that causes the grinding wheel to fit against the cutting edge is collected to determine the position data of the cutting edge extension direction.

[0015] A grinding trajectory curve representing the curvature of the cutting edge is generated based on the position data.

[0016] As an optional solution to the grinding trajectory determination method of the aforementioned sharpening robot, the step of controlling the grinding wheel to move along the X-axis within the grinding range and collecting the extension and retraction amount in the Y-axis direction of the grinding wheel that causes the grinding wheel to align with the cutting edge, and determining the position data of the cutting edge extension direction, includes: Within the grinding range, the positional offset of the grinding wheel in the Y-axis direction is collected synchronously and continuously or intermittently to obtain a set of coordinate data.

[0017] As an optional method for determining the grinding trajectory of the grinding robot, a method for synchronously and continuously acquiring the positional offset of the grinding wheel in the Y-axis direction within the grinding range includes: During the process of the driving mechanism driving the grinding wheel to move at a constant speed along the X-axis, the Y-axis offset data is continuously collected, and the grinding trajectory curve is generated by a curve fitting algorithm.

[0018] As an optional method for determining the grinding trajectory of the grinding robot, a method for synchronously and intermittently acquiring the positional offset of the grinding wheel in the Y-axis direction within the grinding range includes: The drive mechanism is controlled to move the grinding wheel along the X-axis by a preset step length and then stop; At the stop position, the follow-up adapter is controlled to drive the grinding wheel to extend and retract, so that the grinding wheel contacts the cutting edge to detect the current Y-axis coordinate; Repeat the above movement and detection process to collect multiple sets of discrete coordinates until the entire grinding range is covered; The grinding trajectory curve is generated based on multiple sets of discrete coordinates using a linear interpolation algorithm.

[0019] The beneficial effects of this invention are: The knife-grinding robot provided by this invention fixes the knife to a fixed mechanism. A drive mechanism drives the grinding wheel to reciprocate along the extension direction of the cutting edge, while a follower mechanism drives the grinding wheel to extend and retract along a direction perpendicular to the cutting edge, ensuring that the working surface of the grinding wheel remains in contact with the cutting edge. A detection mechanism detects the positions of the shank and tip of the cutting edge during movement, determining the grinding range. Within this range, the drive mechanism controls the grinding wheel to move along the extension direction of the cutting edge, while the follower mechanism dynamically extends and retracts the grinding wheel to maintain contact. This allows the grinding wheel to actively adapt to and conform to the actual curvature or micro-undulations of the cutting edge. Through dynamic extension and retraction compensation, the contact pressure of the grinding wheel on each point of the cutting edge remains essentially constant. Regardless of whether the cutting edge is straight, slightly curved, or has localized wear, uniform grinding along its entire length can be achieved, avoiding localized over-grinding or under-grinding, significantly improving the uniformity and sharpness of the cutting edge.

[0020] The grinding trajectory determination method for a grinding robot provided by this invention establishes a coordinate system by using the direction of reciprocating movement of the grinding wheel driven by the drive mechanism as the X-axis and the direction of extension and retraction of the grinding wheel driven by the follower-adapter mechanism as the Y-axis. Then, the grinding wheel is moved under control, and the coordinates of the shank end and the tip of the blade are detected to determine the grinding range. This converts the position of the tool and the grinding range into precise digital coordinates, providing a benchmark for subsequent automated models. Within the grinding range, as the grinding wheel moves along the X-axis, the amount of extension and retraction of the grinding wheel along the Y-axis to align with the cutting edge is collected, determining the positional data of the cutting edge's extension direction. Essentially, this is a high-precision "three-dimensional scan" of the cutting edge contour, generating a grinding trajectory curve that is a digital model of the true geometry of the cutting edge. This curve acts like a precise "navigation path" for the grinding wheel, allowing it to "know" in advance the undulations of the cutting edge, thereby instructing the drive mechanism and the follower-adapter mechanism to coordinate their movements, ensuring the uniformity and consistency of the grinding process. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the knife-grinding robot provided in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram illustrating the principle of the detection mechanism for the grinding robot's detection endpoint position according to Embodiment 1 of the present invention. Figure 1 ; Figure 3 This is a schematic diagram illustrating the principle of the detection mechanism for the grinding robot's detection endpoint position according to Embodiment 1 of the present invention. Figure 2 ; Figure 4This is a flowchart of the grinding trajectory determination method for the grinding robot provided in Embodiment 2 of the present invention.

[0022] In the picture: 100. Knife; 101. Knife body; 1011. Blade; 10111. Handle end; 10112. Tip of the blade; 102. Handle; 1. Fixing mechanism; 11. Fixing platform; 12. Clamping assembly; 121. Clamping plate; 2. Grinding wheel; 21. Working surface; 3. Drive mechanism; 31. Second motor; 32. Second lead screw; 33. Slide; 4. Follow-up adaptation mechanism; 41. Bracket; 42. Telescopic drive assembly; 421. First motor; 422. First lead screw; 423. Telescopic arm; 424. First lead screw nut; 43. Spring; 5. Guide assembly; 51. Guide rail; 6. Third motor; 7. Photoelectric sensor; 71. Light source transmitter; 72. Light source receiver. Detailed Implementation

[0023] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0024] Unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and connections within two components or interactions between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0025] Unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of a second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0026] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0027] Example 1: like Figures 1-3 As shown, this embodiment provides a knife-grinding robot, including a frame, a fixing mechanism 1, a grinding wheel 2, a drive mechanism 3, a follower-adaptor mechanism 4, and a detection mechanism. The fixing mechanism 1 and the drive mechanism 3 are both mounted on the frame. The fixing mechanism 1 is used to fix the cutting tool 100; the working surface 21 of the grinding wheel 2 is positioned opposite to the cutting edge 1011 of the cutting tool 100; the drive mechanism 3 is used to drive the grinding wheel 2 to reciprocate along the extension direction of the cutting edge 1011; the follower-adaptor mechanism 4 is connected between the drive mechanism 3 and the grinding wheel 2, and is used to drive the grinding wheel 2 to extend and retract along a direction perpendicular to the extension direction of the cutting edge 1011 when the grinding wheel 2 moves, so that the working surface 21 remains in contact with the cutting edge 1011. The detection mechanism is used to detect the position of the shank end 10111 and the tip 10112 of the cutting edge 1011 during the movement of the grinding wheel 2.

[0028] The grinding robot provided in this embodiment fixes the cutting tool 100 to the fixing mechanism 1. The driving mechanism 3 drives the grinding wheel 2 to reciprocate along the extension direction of the cutting edge 1011, while the follower-adapter mechanism 4 drives the grinding wheel 2 to extend and retract along a direction perpendicular to the extension direction of the cutting edge 1011, so that the working surface 21 of the grinding wheel 2 remains in contact with the cutting edge 1011. The detection mechanism can detect the positions of the shank end 10111 and the tip 10112 of the cutting edge 1011 during movement, determining the grinding range of the cutting tool 100. Within the grinding range, the driving mechanism 3 controls the grinding wheel 2 to move along the extension direction of the cutting edge 1011, while simultaneously controlling the follower-adapter mechanism 4 to dynamically extend and retract the grinding wheel 2 to maintain contact. This allows the grinding wheel 2 to actively adapt to and conform to the actual curvature or micro-undulations of the cutting edge 1011. Through dynamic extension and retraction compensation, the contact pressure of the grinding wheel 2 on each point of the cutting edge 1011 remains essentially constant. Regardless of whether the 1011 cutting edge is straight, slightly curved, or has localized wear, it can achieve uniform grinding along its entire length, avoiding localized "over-grinding" or "under-grinding," and significantly improving the uniformity and consistency of the cutting edge.

[0029] The fixing mechanism 1 includes a fixing platform 11 and a clamping assembly 12 disposed on the fixing platform 11. The clamping assembly 12 is used to clamp the cutting tool 100. The grinding wheel 2 is provided with a grinding groove for accommodating the cutting edge of the cutting tool 100. The included angle of the grinding groove matches the target grinding angle of the cutting tool 100. The working surface 21 of the grinding wheel 2 is the vertex of the included angle of the grinding groove.

[0030] The cutting tool 100 includes a shank 102 and a body 101. The shank 102 is typically connected to the upper part of the tail end of the body 101, and the lower part of the body 101 is the cutting edge 1011. The upper surface of the fixing platform 11 is a reference plane. When fixing the cutting tool 100, the cutting edge 1011 of the body 101 is placed upward on the reference plane, and the clamping assembly 12 clamps the upper part of the body 101 so that the body 101 is fixed during the grinding process and the posture of the cutting edge 1011 does not change.

[0031] Specifically, the clamping assembly 12 includes two opposing clamping plates 121 and a clamping drive that drives the two clamping plates 121 to move towards or away from each other. The clamping drive drives the two clamping plates 121 to move towards each other, so that the side of the two clamping plates 121 that is close to each other abuts against the two sides of the blade body 101, thereby clamping the blade body 101. The clamping drive can be a fourth motor and a bidirectional screw. The two clamping plates 121 are provided with threaded holes opposite each other, and the bidirectional screw is provided with a left-hand threaded section and a right-hand threaded section. The threaded hole on one clamping plate 121 is screwed into the left-hand threaded section, and the threaded hole on the other clamping plate 121 is screwed into the right-hand threaded section. The fourth motor is connected to the bidirectional screw and drives the bidirectional screw to rotate. The bidirectional screw drives the two clamping plates 121 to move towards or away from each other, thereby realizing the clamping of the blade body 101 or the release of the blade body 101 by the two clamping plates 121.

[0032] In one embodiment, the drive mechanism 3 includes a second motor 31, a second lead screw 32, and a slide 33. The second motor 31 is connected to the second lead screw 32 and is used to drive the second lead screw 32 to rotate. The second lead screw 32 is connected to the slide 33 in a transmission manner. A follower-adapter mechanism 4 is disposed on the slide 33. The second motor 31 drives the second lead screw 32 to rotate, and the second lead screw 32 drives the slide 33 to move along the axis of the second lead screw 32. Then, the slide 33 drives the grinding wheel 2 to move through the follower-adapter mechanism 4. The second motor 31 can rotate in both directions to realize the reciprocating movement of the grinding wheel 2, thereby realizing the reciprocating grinding of the cutting edge 1011 until the tip of the cutting edge 1011 of the tool 100 contacts the bottom of the grinding groove, and the grinding of the cutting edge 1011 is completed.

[0033] Specifically, the second motor 31 is preferably a servo motor or stepper motor with an encoder. The second motor 31 is fixed to the frame by a mounting bracket. The output shaft of the second motor 31 is coaxially connected to the second lead screw 32 through a coupling to ensure transmission accuracy and efficiency. The two ends of the second lead screw 32 are supported by bearings, which are installed in bearing housings to achieve high rigidity or low friction rotational motion.

[0034] The slide block 33 is a rigid metal component, and it integrates a second lead screw nut that mates with the second lead screw 32, forming a transmission connection. The follower adapter 4 is fixed to the bottom surface of the slide block 33 via a mounting platform.

[0035] In one embodiment, the grinding robot further includes a guide assembly 5, which includes guide rails 51 arranged parallel to both sides of the second lead screw 32, and a slide block 33 slidably connected to the guide rails 51. A guide rail 51 is provided on each side of the second lead screw 32, and grooves are provided on both sides of the bottom surface of the slide block 33. The grooves cooperate with the guide rails 51 to provide guidance for the slide block 33 when the second motor 31 drives the slide block 33 to reciprocate through the second lead screw 32, ensuring that the slide block 33 does not deviate during movement, thereby ensuring that the grinding groove of the grinding wheel 2 always precisely matches the cutting edge 1011, improving the grinding effect.

[0036] In one embodiment, the follower-adapter mechanism 4 includes a bracket 41, a telescopic drive assembly 42, and an elastic preload element. The bracket 41 is used to mount the grinding wheel 2. The telescopic drive assembly 42 is connected to the bracket 41 and is used to provide power for the telescopic extension and retraction of the grinding wheel 2. The elastic preload element is disposed between the telescopic drive assembly 42 and the bracket 41 and is used to provide a preload force that continuously presses against the cutting edge 1011 of the grinding wheel 2.

[0037] The bracket 41 includes a top plate and side plates that are perpendicularly connected to both sides of the top plate. The grinding wheel 2 is installed between the two side plates. A third motor 6 is installed on the outside of one of the side plates. The spindle of the third motor 6 passes through the side plate and is connected to the center hole of the grinding wheel 2. While the third motor 6 drives the grinding wheel 2 to rotate, the telescopic drive assembly 42 drives the bracket 41 to extend and retract so that the grinding groove of the grinding wheel 2 is always in contact with the cutting edge 1011.

[0038] During grinding, the telescopic drive assembly 42 sets a reference height, while the elastic preload element provides a constant initial force that presses the grinding wheel 2 against the cutting edge 1011. When the cutting edge 1011 is locally too high or the grinding wheel 2 wears, the elastic preload element is further compressed to buffer the pressure; when the cutting edge 1011 is locally too low, the elastic preload element is released, pushing the support 41 downward to maintain contact with the cutting edge 1011.

[0039] In one embodiment, the telescopic drive assembly 42 includes a first motor 421, a first lead screw 422, and a telescopic arm 423. The first motor 421 is connected to the first lead screw 422 and is used to drive the first lead screw 422 to rotate. The first lead screw 422 is connected to the telescopic arm 423 for transmission, and the telescopic arm 423 is fixedly connected to the bracket 41. The first motor 421 is a stepper motor or a servo motor. The fixed end of the first motor 421 is fixed on the slide 33, the output shaft is arranged downward, and it is connected to the first lead screw 422 through a coupling. The telescopic arm 423 is configured as a telescopic sleeve. The first motor 421 and the first lead screw 422 are located inside the telescopic sleeve. The telescopic sleeve includes a fixed tube and a telescopic tube sleeved inside the fixed tube. The fixed tube is connected to the installation platform. The first lead screw 422 is connected to the telescopic tube through the first lead screw nut 424. The bottom of the telescopic tube is connected to the top plate of the bracket 41. The first motor 421 drives the first lead screw 422 to rotate. The first lead screw 422 drives the telescopic tube to extend and retract through the first lead screw nut 424. The telescopic tube drives the grinding wheel 2 to extend and retract through the bracket 41.

[0040] The telescopic tube's extension and retraction are precisely controlled by the step size of the first motor 421. The angle at which the first motor 421 rotates is fixed for each drive pulse (i.e., one step size). The extension and retraction are calculated based on the linear distance moved by the first lead screw nut 424 that cooperates with it as the first lead screw 422 rotates one revolution.

[0041] Specifically, the elastic preload element is a spring 43, with its two ends abutting against the output end of the telescopic drive assembly 42 and the bracket 41, respectively. The spring 43 is sleeved on the first lead screw 422, with one end connected to the first lead screw nut 424 and the other end connected to the top plate of the bracket 41. When the first motor 421 drives the first lead screw 422 to rotate, it causes the first lead screw nut 424 to move the telescopic tube and one end of the spring 43 simultaneously, thereby rapidly transmitting the position change to the bracket 41 and completing the macroscopic position setting of the grinding wheel 2. Simultaneously, the elastic force of the spring 43 can compensate for minor positional changes caused by wear of the grinding groove or localized changes in the cutting edge 1011.

[0042] In one embodiment, the detection mechanism includes a photoelectric sensor 7, which includes a light source emitting end 71 and a light source receiving end 72. The light source emitting end 71 and the light source receiving end 72 are disposed opposite each other on both sides of the blade 1011 to generate a trigger signal when the blade 1011 enters or leaves the detection area. The detection mechanism is mounted on a bracket 41. Specifically, the light source emitting end 71 and the light source receiving end 72 are disposed opposite each other on the inner walls of the two side plates of the bracket 41.

[0043] An invisible "light curtain" is formed between the light source emitter 71 and the light source receiver 72. When the follow-up adapter mechanism 4 drives the grinding wheel 2 and the photoelectric sensor 7 to move to the tip of the cutting edge 1011, the cutting edge 1011 will block the light path for the first time, triggering a signal change. The photoelectric sensor 7 has no physical contact with the cutting edge 1011, so it will not cause any scratches or wear to the precision cutting edge, and it also avoids mechanical wear on the photoelectric sensor 7 itself. The response of the light signal is in the millisecond or even microsecond range, making the tip detection action very fast.

[0044] In other embodiments, the detection mechanism may also be an inductive proximity switch. The inductive proximity switch has a built-in oscillating coil. When the metal blade 1011 approaches within the sensing distance, it causes a change in the coil parameters, outputting a switching signal. Alternatively, the detection mechanism may be a resistance sensor, mounted on the first motor 421. When the grinding wheel 2 contacts the blade 1011, the resistance of the first motor 421 increases, and the resistance sensor detects this change in resistance.

[0045] In one embodiment, the detection plane of the detection mechanism is closer to the fixed mechanism 1 than the working surface 21, and offset by a fixed preset distance H in the direction closer to the fixed mechanism 1. The driving mechanism 3 and the follower-adapter mechanism 4 drive the grinding wheel 2 and the detection mechanism to move. When the cutting edge 1011 blocks the light, the detection mechanism triggers a signal, indicating that the detection plane intersects with the cutting edge 1011. At this time, the spatial coordinates of the trigger point are recorded. Since the spatial relationship between the detection plane and the working surface 21 and the offset H are pre-calibrated and stored, the compensation amount required to bring the working surface 21 to the same longitudinal position can be calculated. Subsequently, the follower-adapter mechanism 4 is controlled to drive the grinding wheel 2 to move precisely by the preset distance H in the direction closer to the fixed mechanism 1, so that the working surface 21 of the grinding wheel 2 contacts the cutting edge 1011, completing the alignment before grinding.

[0046] In one embodiment, the grinding robot further includes a control unit, which is electrically connected to the drive mechanism 3, the follower-adapter mechanism 4, and the detection mechanism. The control unit is configured to: determine the endpoint coordinates of the cutting edge 1011 based on signals from the detection mechanism; and control the drive mechanism 3 and the follower-adapter mechanism 4 to coordinate their actions based on the endpoint coordinates, causing the grinding wheel 2 to move along the fitted trajectory of the cutting edge 1011. The control unit receives feedback signals from the detection mechanism and performs digital calculations and decisions accordingly, precisely controlling the actions of the drive mechanism 3 and the follower-adapter mechanism 4; ensuring high consistency and repeatability of different cutting tools 100 and different grinding structures.

[0047] Example 2: like Figure 4 As shown, this embodiment provides a method for determining the grinding trajectory of a sharpening robot, applied to the sharpening robot provided in Embodiment 1. The method for determining the grinding trajectory includes: S10. Fix the tool 100 to the fixing mechanism 1, and establish a coordinate system by taking the direction of the reciprocating movement of the grinding wheel 2 driven by the driving mechanism 3 as the X-axis and the direction of the extension and retraction of the grinding wheel 2 driven by the follower-adapter mechanism 4 as the Y-axis.

[0048] During grinding, the tool 100 is first placed between two clamping plates 121 with the cutting edge 1011 facing upwards, and the tool body 101 is fixed so that the cutting edge 1011 is exposed. The control unit defines and stores a two-dimensional coordinate system according to the structural layout of the grinding robot. The direction of the reciprocating movement of the grinding wheel 2 driven by the drive mechanism 3 is defined as the X-axis, which is parallel to the extension direction of the cutting edge 1011; the direction of the vertical extension and retraction movement of the grinding wheel 2 driven by the follower adaptation mechanism 4 is defined as the Y-axis. The establishment of the coordinate system provides a mathematical basis for the subsequent digital determination of the actual spatial contour of the cutting edge 1011 by collecting the Y-axis coordinates required for the grinding wheel 2 to contact the cutting edge 1011 at different X-axis positions.

[0049] S20. Control the drive mechanism 3 to drive the grinding wheel 2 to move, and control the follow-up adapter mechanism 4 to drive the grinding wheel 2 to extend and retract. Use the detection mechanism to detect the tool holder end 10111 and the tool tip 10112 of the cutting edge 1011, and record the coordinates of the tool holder end 10111 and the tool tip 10112 to determine the grinding range.

[0050] Before grinding, first determine the position of the shank end 10111 and the tip 10112 of the cutting edge 1011 to determine the grinding range, that is, the range of movement of the grinding wheel 2 along the X and Y axes.

[0051] The control drive mechanism 3 drives the grinding wheel 2 and the detection mechanism fixed thereon to move along the X-axis until they reach the preset starting area corresponding to the tool holder end 10111 of the tool 100. The control telescopic drive assembly 42 drives the telescopic tube to extend, causing the grinding wheel 2 to move closer to the cutting edge 1011. The photoelectric sensor 7 moves with the grinding wheel 2. When the cutting edge 1011 first blocks the light path, the photoelectric sensor 7 sends a signal to the control unit. At this time, the control unit records the spatial coordinates (X-axis and X-axis) of the trigger point of the tool holder end 10111. 刀柄 ,Y 刀柄 According to the pre-calibrated photoelectric sensor 7, whose detection plane is offset by a preset distance H on the Y-axis from the vertex of the angle between the angle between the sensor 7 and the grinding groove of the grinding wheel 2, the position coordinates of the tool holder end 10111 are (X... 刀柄 ,Y 刀柄+H). Once the position coordinates of the tool holder end 10111 are determined, the drive mechanism 3 is controlled to drive the grinding wheel 2 to move to the position corresponding to the tool tip 10112 in the X-axis direction. Then, the telescopic drive assembly 42 is controlled to drive the grinding wheel 2 to extend, causing the grinding wheel 2 to move closer to the cutting edge 1011. The photoelectric sensor 7 moves with the grinding wheel 2. When the cutting edge 1011 first blocks the light path, the photoelectric sensor 7 sends a signal to the control unit. At this time, the control unit records the spatial coordinates (X) of the tool tip trigger point. 刀尖 ,Y 刀尖 Since the detection plane of the photoelectric sensor 7 is offset by a preset distance H from the working surface 21 of the grinding wheel 2 on the Y-axis, the position coordinates of the tool holder end 10111 are (X... 刀尖 ,Y 刀尖 +H).

[0052] The control unit will calculate the coordinates (X) of the tool holder end 10111. 刀柄 ,Y 刀柄 +H) and the 10112 coordinates of the tool tip (X) 刀尖 ,Y 刀尖 +H) is determined as the effective grinding range endpoint of the cutting edge 1011. Based on the coordinates of these two endpoints, the working space range of the grinding wheel 2 is defined in the coordinate system, that is, the travel range on the X-axis is (X 刀柄 X 刀尖 This provides a benchmark for subsequent contour tracking and grinding operations within this range.

[0053] S30. Within the grinding range, control the grinding wheel 2 to move along the X-axis and collect the amount of extension and retraction of the grinding wheel 2 in the Y-axis direction so that the grinding wheel 2 and the cutting edge 1011 are in contact, and determine the position data of the extension direction of the cutting edge 1011.

[0054] Specifically, within the grinding range, the positional offset of the grinding wheel 2 in the Y-axis direction is collected synchronously and continuously or intermittently to obtain a set of coordinate data.

[0055] In one embodiment, the method for synchronously and continuously collecting the positional offset of the grinding wheel 2 in the Y-axis direction within the grinding range includes: continuously collecting Y-axis offset data while the driving mechanism 3 drives the grinding wheel 2 to move at a constant speed along the X-axis, and using a curve fitting algorithm to generate a grinding trajectory curve.

[0056] The control unit determines the grinding range (X) based on the endpoint coordinates. 刀柄 X 刀尖 After that, the control unit sends a command to the drive mechanism 3, causing it to drive the grinding wheel 2 from the tool holder end at coordinate X. 刀柄 Start along the X-axis towards the tool tip at coordinate X10112. 刀尖 It moves at a constant speed in the direction.

[0057] During the uniform speed movement, the control unit synchronously performs the following operations: by using the step size of the second motor 31, it reads and records the current X-axis coordinate of the grinding wheel 2 in real time. i The step size of the first motor 421 is used to read and measure the real-time Y-axis position offset Y required to maintain contact between the grinding wheel 2 and the cutting edge 1011. i .

[0058] Each set of synchronous recording locations (X) i ,Y i This constitutes a data point representing the profile of the cutting edge 1011. Within the entire grinding range (X1, X2), hundreds to thousands of such data points will be collected, forming a set {(X1, Y1), (X2, Y2), ..., (X...}. n ,Y n )}.

[0059] In one embodiment, the method for synchronously and intermittently acquiring the positional offset of the grinding wheel 2 in the Y-axis direction within the grinding range includes: controlling the drive mechanism 3 to drive the grinding wheel 2 to move along the X-axis by a preset step length and stop; at the stop position, controlling the follower adapter 4 to drive the grinding wheel 2 to extend and retract, so that the grinding wheel 2 contacts the cutting edge 1011 to detect the current Y-axis coordinate; repeating the above movement and detection process to acquire multiple sets of discrete coordinates until the entire grinding range is covered; and generating a grinding trajectory curve based on the multiple sets of discrete coordinates using a linear interpolation algorithm.

[0060] The control unit determines the grinding range (X) based on the predefined grinding range. 刀柄 X 刀尖 The preset step size ΔX is set, which is 0.5mm or 1mm. The control unit controls the drive mechanism 3 to position the grinding wheel 2 to the grinding starting point, that is, the tool holder end 10111 at the X-axis coordinate X. 刀柄 Place.

[0061] The control unit executes a cyclic acquisition process until the entire grinding range is covered: the control drive mechanism 3 drives the grinding wheel 2 to move a preset step size ΔX along the positive X-axis, and then precisely stops at the new position X. i .

[0062] At the stop position X i The control unit commands the follow-up adapter 4 to drive the grinding wheel 2 to extend along the Y-axis towards the cutting edge 1011. During this process, the photoelectric sensor 7 detects and determines that the working surface 21 of the grinding wheel 2 is in contact with the cutting edge 1011. At the moment of contact determination, the control unit synchronously records the precise position of the grinding wheel 2 in the coordinate system at this moment through the step size of the second motor 31 and the first motor 421, obtaining a discrete contour coordinate point (X).i ,Y i ), and store it in memory. Repeat the above loop. After each loop, check the current X-axis position X. i Has the grinding endpoint X been reached or exceeded? 刀尖 If the target is not reached, continue to the next iteration; if the target is reached, terminate data acquisition. Ultimately, a sequence of discrete coordinate points arranged in X-axis order is obtained: {(X1,Y1),(X1+ΔX,Y2),……,(X...} n ,Y n )}.

[0063] S40. Generate a grinding trajectory curve representing the 1011 arc degree of the cutting edge based on the position data.

[0064] After obtaining the above set of data points, the control unit calls a preset curve fitting algorithm for processing.

[0065] For the data point set obtained within the grinding range by synchronously acquiring the positional offset of the grinding wheel 2 in the Y-axis direction, a cubic polynomial smoothing curve fitting algorithm using the least squares method is preferred. The algorithm aims to find a curve of the form Y = a0 + a1 × X + a2 × X. 2 +a3×X 3 A cubic polynomial curve, such that the curve is consistent with all collected data points (X). i ,Y i The sum of the squares of the vertical distances between the components is minimized. The control unit calculates and determines the optimal coefficients a0, a1, a2, a3 using a standard mathematical library. Substituting the calculated coefficients into the polynomial generates a smooth, continuous mathematical function Y=f(X). This function curve is the grinding trajectory curve, which accurately describes the geometric relationship between the profile (Y-axis position) of the cutting edge 1011 and the X-axis position within the grinding range.

[0066] For the discrete coordinate point sequence arranged in X-axis order obtained by intermittently acquiring the position offset of the grinding wheel 2 in the Y-axis direction within the grinding range, the control unit organizes the acquired discrete coordinate point sequence and calls a preset linear interpolation algorithm to interpolate between every two adjacent discrete coordinate points (X... i ,Y i ) and (X {i+1} ,Y {i+1} Connect the points between them with a straight line segment. Specifically, for points located on the X-axis... i and X {i+1} For any point X between X and Y, its corresponding Y-axis coordinate value Y is calculated using the following interpolation formula: Y = Y i +{(Y {i+1} -Y i ) / (X{i+1} -X i )}×(XX i By connecting all adjacent points with straight line segments in sequence, a piecewise linear continuous trajectory curve is formed. This broken line is an approximate model of the 1011 radian of the cutting edge, serving as the path basis for the subsequent tracking motion of the grinding wheel 2.

[0067] The above description is only a preferred embodiment of the present invention. For those skilled in the art, there will be changes in the specific implementation and application scope based on the ideas of the present invention. The content of this specification should not be construed as a limitation of the present invention.

Claims

1. A knife-sharpening robot, characterized in that, include: A fixing mechanism (1) is used to fix the cutting tool (100); A grinding wheel (2) is provided with its working surface (21) facing the cutting edge (1011) of the cutting tool (100). The driving mechanism (3) is used to drive the grinding wheel (2) to reciprocate along the extension direction of the cutting edge (1011); The follow-up adapter (4) is connected between the drive mechanism (3) and the grinding wheel (2) and is used to drive the grinding wheel (2) to extend and retract in a direction perpendicular to the cutting edge (1011) when the grinding wheel (2) moves, so that the working surface (21) and the cutting edge (1011) remain in contact. The detection mechanism is used to detect the position of the shank end (10111) and the tip (10112) of the cutting edge (1011) during the movement of the grinding wheel (2).

2. The knife-grinding robot according to claim 1, characterized in that, The detection mechanism includes a photoelectric sensor (7), which includes a light source emitting end (71) and a light source receiving end (72). The light source emitting end (71) and the light source receiving end (72) are arranged opposite to each other on both sides of the blade (1011) to generate a trigger signal when the blade (1011) enters or leaves the detection area.

3. The knife-grinding robot according to claim 2, characterized in that, The detection plane of the detection mechanism is closer to the fixing mechanism (1) relative to the working surface (21).

4. The knife-grinding robot according to claim 1, characterized in that, The follow-up adaptation mechanism (4) includes: A bracket (41) is used to mount the grinding wheel (2); A telescopic drive assembly (42), connected to the bracket (41), is used to provide power for the telescopic movement of the grinding wheel (2); An elastic preload element is disposed between the telescopic drive assembly (42) and the bracket (41) to provide a preload force to the grinding wheel (2) that continuously presses against the cutting edge (1011).

5. The knife-grinding robot according to claim 4, characterized in that, The telescopic drive assembly (42) includes a first motor (421), a first lead screw (422), and a telescopic arm (423). The first motor (421) is connected to the first lead screw (422) and is used to drive the first lead screw (422) to rotate. The first lead screw (422) is connected to the telescopic arm (423) in a transmission connection. The telescopic arm (423) is fixedly connected to the bracket (41).

6. The knife-grinding robot according to claim 4, characterized in that, The detection mechanism is mounted on the support (41).

7. The knife-grinding robot according to claim 1, characterized in that, The drive mechanism (3) includes a second motor (31), a second lead screw (32) and a slide (33). The second motor (31) is connected to the second lead screw (32) and is used to drive the second lead screw (32) to rotate. The second lead screw (32) is connected to the slide (33) in a transmission connection. The follower adapter (4) is disposed on the slide (33).

8. The knife-grinding robot according to claim 7, characterized in that, The knife-sharpening robot also includes a guide assembly (5), which includes guide rails (51) arranged parallel to both sides of the second lead screw (32), and the slide (33) is slidably connected to the guide rails (51).

9. The knife-grinding robot according to any one of claims 1-8, characterized in that, The knife-sharpening robot also includes a control unit, which is electrically connected to the drive mechanism (3), the follow-up adaptation mechanism (4), and the detection mechanism, and is configured as follows: The endpoint coordinates of the blade (1011) are determined based on the signal from the detection mechanism; The drive mechanism (3) and the follower adaptation mechanism (4) are controlled to work together according to the endpoint coordinates, so that the grinding wheel (2) moves along the fitted cutting edge (1011) trajectory.

10. A method for determining the grinding trajectory of a tool-grinding robot, characterized in that, Applied to the grinding robot as described in any one of claims 1-9, the grinding trajectory determination method includes: The tool (100) is fixed to the fixing mechanism (1), and the direction of the reciprocating movement of the grinding wheel (2) driven by the driving mechanism (3) is taken as the X-axis, and the direction of the extension and retraction of the grinding wheel (2) driven by the follower adapter mechanism (4) is taken as the Y-axis, and a coordinate system is established. The drive mechanism (3) is controlled to drive the grinding wheel (2) to move, and the follow-up adapter mechanism (4) is controlled to drive the grinding wheel (2) to extend and retract. The detection mechanism is used to detect the shank end (10111) and the tip (10112) of the cutting edge (1011), and the coordinates of the shank end (10111) and the tip (10112) are recorded to determine the grinding range. Within the grinding range, the grinding wheel (2) is controlled to move along the X-axis, and the amount of extension and retraction of the grinding wheel (2) in the Y-axis direction that makes the grinding wheel (2) fit with the cutting edge (1011) is collected to determine the position data of the extension direction of the cutting edge (1011); Based on the position data, a grinding trajectory curve representing the curvature of the cutting edge (1011) is generated.

11. The method for determining the grinding trajectory of a grinding robot according to claim 10, characterized in that, The steps of controlling the grinding wheel (2) to move along the X-axis within the grinding range and collecting the extension and retraction of the grinding wheel (2) in the Y-axis direction so that the grinding wheel (2) and the cutting edge (1011) are in contact, and determining the position data of the extension direction of the cutting edge (1011) include: Within the grinding range, the positional offset of the grinding wheel (2) in the Y-axis direction is collected synchronously and continuously or intermittently to obtain a set of coordinate data.

12. The method for determining the grinding trajectory of a grinding robot according to claim 11, characterized in that, The method for synchronously and continuously acquiring the positional offset of the grinding wheel (2) in the Y-axis direction within the grinding range includes: During the process of the drive mechanism (3) driving the grinding wheel (2) to move at a constant speed along the X-axis, the Y-axis offset data is continuously collected, and the grinding trajectory curve is generated by the curve fitting algorithm.

13. The method for determining the grinding trajectory of a grinding robot according to claim 11, characterized in that, Within the grinding range, a method for synchronously and intermittently acquiring the positional offset of the grinding wheel (2) in the Y-axis direction includes: The drive mechanism (3) is controlled to drive the grinding wheel (2) to move along the X-axis by a preset step length and then stop; At the stop position, the follow-up adapter (4) is controlled to drive the grinding wheel (2) to extend and retract, so that the grinding wheel (2) contacts the cutting edge (1011) to detect the current Y-axis coordinate; Repeat the above movement and detection process to collect multiple sets of discrete coordinates until the entire grinding range is covered; The grinding trajectory curve is generated based on multiple sets of discrete coordinates using a linear interpolation algorithm.

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