A device and method for detecting axial runout of a bicycle chainring

Abstract

The application discloses a bicycle chain wheel axial deflection detection device and a control method, which comprises a detection module arranged on a rack and a diameter-expanding automatic telescopic locking clamp for fixing a chain wheel. The detection module comprises a laser displacement sensor and a guide rod part which can reciprocate along a laser beam path and serve as a laser receiving end. The detection module is arranged on a moving end of a single-shaft driver, and the single-shaft driver can drive the guide rod part to elastically abut on the outer ring gear teeth. The diameter-expanding automatic telescopic locking clamp can be driven to rotate by a stepping motor. The application aims to provide a bicycle chain wheel axial deflection detection device and a control method, which can convert the axial deflection of adjacent gear teeth into the axial deflection of a detection plane by the sliding of the guide rod part, and then measure the axial deflection of the detection plane by a laser displacement sensor to detect the axial deflection of the chain wheel.

Description

Technical Field

[0001] This invention relates to the field of bicycle sprocket axial runout detection technology, specifically to a bicycle sprocket axial runout detection device and control method. Background Technology

[0002] The commonly seen multi-speed bicycles in daily life change speed by altering the gear ratio of the sprocket and freewheel. Since the sprockets of different sizes on the chainring are located on two different planes, excessive axial runout of the sprockets may cause the chain to slip off when switching between the two sprockets, affecting the reliability of the shifting system.

[0003] Therefore, during the sprocket manufacturing process, it is necessary to detect the axial runout of the sprocket.

[0004] In existing technologies, the entire axial runout detection process for sprockets requires manual operation. The sprocket is manually clamped and secured using an interference fit between the shaft and hole. During testing, the sprocket is rotated by manually turning a handle, ensuring that different teeth contact the dial indicator. Throughout the process, the worker must simultaneously turn the handle and judge the axial runout of the teeth based on the dial indicator reading. This method has the following drawbacks: 1. Eye fatigue from prolonged reading can lead to inconsistent standards for judging runout by the same person at different times; 2. Visual inspection relies heavily on the operator's experience, resulting in high costs; 3. Human visual inspection readings are inevitably prone to errors, leading to inconsistent standards; 4. The sprocket clamping method is not only inefficient but also easily causes scratches on the surface of the parts.

[0005] Therefore, how to provide a bicycle sprocket axial runout detection device that is versatile, efficient and accurate is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a bicycle sprocket axial runout detection device and control method, which can convert the axial runout of adjacent teeth into the axial runout of the detection plane by sliding the guide rod, and then detect the axial runout of the sprocket by measuring the axial runout of the detection plane through a laser displacement sensor.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a bicycle sprocket axial runout detection device, comprising a detection module mounted on a frame and an expanded diameter automatic telescopic locking clamp for fixing the sprocket, wherein the detection module comprises a laser displacement sensor and a guide rod that can reciprocate along the laser beam path and serves as a laser receiving end;

[0008] The detection module is located at the moving end of the single-axis driver, which can drive the guide rod to elastically abut against the outer ring gear teeth.

[0009] The expanded diameter automatic telescopic locking clamp can be driven to rotate by a stepper motor.

[0010] In a preferred embodiment of the present invention, the guide rod includes a fixed seat connected to the moving end of the single-axis driver and a detection guide rod slidably connected to the fixed seat. A laser receiving plate is provided at one end of the detection guide rod facing the laser beam. The laser receiving plate is slidably sleeved on the outer periphery of a limiting rod provided on the fixed seat and parallel to the detection guide rod. A first spring is also sleeved on the outer periphery of the limiting rod and disposed between the laser receiving plate and the fixed seat.

[0011] A contact plate is provided at one end of the detection guide rod that can abut against the outer ring gear teeth, and the length of the contact plate is greater than the distance between two adjacent outer ring gear teeth on the sprocket.

[0012] In a preferred embodiment of the present invention, a reset button connected to the single-axis driver and the stepper motor signal is provided on the frame.

[0013] An expanding-diameter automatic telescopic locking clamp includes an expanding-diameter tensioning mechanism, an automatic telescopic locking mechanism, and a combined sealing cover covering the outer periphery of the expanding-diameter tensioning mechanism and the automatic telescopic locking mechanism.

[0014] The expansion and tightening mechanism includes a positioning sleeve disposed at the end of the combined sealing cover, an expansion drive rod with one end slidably embedded in the positioning sleeve, and a plurality of expansion pressure blocks respectively slidably sleeved on the expansion drive rod and slidably embedded on the positioning sleeve. A groove structure is provided between the expansion drive rod and the expansion pressure block.

[0015] The outer periphery of the expansion drive rod is fitted with a first sleeve that is slidably connected to the combined sealing cover. A second spring is provided between the first sleeve and the expansion drive rod, and the two ends of the second spring abut against the bottom side of the inner cavity of the first sleeve and the nail-shaped column head on the expansion drive rod, respectively.

[0016] The automatic telescopic locking mechanism includes an electric cylinder that can push the first sleeve to move.

[0017] In a preferred embodiment of the present invention, the automatic telescopic locking mechanism further includes a second sleeve disposed inside the combined sealing cover and opposite to the first sleeve and capable of moving synchronously, and a third spring is disposed between the second sleeve and the inner cavity sidewall of the combined sealing cover, and the third spring is sleeved on the outer periphery of the limiting post placed on the inner cavity sidewall of the combined sealing cover.

[0018] When the electric cylinder pushes the first sleeve to move, the third spring is compressed, providing power for the second sleeve to reset; the second sleeve is provided with a closed-loop sliding groove, and the other end of the combined sealing cover is provided with a driven rod;

[0019] The driven rod is L-shaped. One end of the driven rod is rotatably connected to the combined sealing cover and can move up and down along the axis of that end. The end of the other end can slide along the closed-loop groove.

[0020] In a preferred embodiment of the present invention, the closed-loop slide includes segments AB, BC, CD, and DA;

[0021] The AB section is divided into a first section, a second section, and a third section. The second section is an ascending gentle slope. The depth of the groove where the first section is located is higher than the depth of the groove where the third section is located. The groove depth of the third section is equal to that of the BC section. The depth of the groove where the DA section is located is between the depths of the grooves where the BC section and the first section are located. A stepped surface is provided at the junction. A stop is formed on the second sleeve by the closed-loop sliding groove.

[0022] In a preferred embodiment of the present invention, a section of the driven rod that is rotatably connected to the combined sealing cover passes through the combined sealing cover and is fitted with a fourth spring on its outer periphery. The two ends of the fourth spring abut against the outer periphery of the combined sealing cover and the nail-shaped post head of that section of the driven rod, respectively.

[0023] A control method for a bicycle sprocket axial runout detection device includes the following steps:

[0024] Step 1: Press the reset button, the single-axis driver drives the detection module to the initial position, and the stepper motor drives the expanding-diameter automatic telescopic locking fixture to the original position;

[0025] Step 2: The sprocket is manually fitted onto the outer circumference of the positioning sleeve. After the electric cylinder drives the expanding-diameter automatic telescopic locking clamp to perform the first corresponding control operation, it is reset, positioning and fixing the sprocket position.

[0026] Step 3: The single-axis driver drives the detection module to move toward the direction of the sprocket until the laser displacement sensor detects a change in distance, at which point the single-axis driver stops advancing.

[0027] Step 4: The laser displacement sensor sets the plane at this time as the detection reference plane, starts the stepper motor to drive the expanded diameter automatic telescopic locking fixture and the sprocket to rotate, and the detection begins. The stepper motor rotates a preset number of times and then stops. The laser displacement sensor collects data and uploads it for analysis.

[0028] Step 5: After the stepper motor stops driving, the single-axis driver resets, and the electric cylinder drives the expanding-diameter automatic telescopic locking fixture to perform the second corresponding control operation before resetting, releasing and removing the sprocket, thus completing one test.

[0029] In a preferred embodiment of the present invention, the specific steps for resetting the expanded-diameter automatic telescopic locking clamp after the electric cylinder drives the clamp to perform the first corresponding control operation include:

[0030] Step A: The electric cylinder pushes the first sleeve and the second sleeve to move synchronously away from the positioning sleeve. The bottom side of the inner cavity of the first sleeve abuts against and compresses the second spring, and the second sleeve abuts against and compresses the third spring. One end of the driven rod slides along the AB segment. Then, the first sleeve pulls the expansion drive rod to move in the same direction through the third spring. The expansion pressure block gradually abuts against the inner wall of the square hole on the sprocket, positioning and fixing the position of the sprocket.

[0031] Step B: The electric cylinder stops pushing the first sleeve and the second sleeve to move and resets;

[0032] Step C: The third spring rebounds, the first sleeve and the second sleeve move in opposite directions, and one end of the driven rod moves along the BC segment until it falls into point C, completing the self-locking.

[0033] In a preferred embodiment of the present invention, the specific steps for resetting the expanded-diameter automatic telescopic locking clamp after the electric cylinder drives the clamp to perform a second corresponding control operation include:

[0034] Step D: The electric cylinder pushes the first sleeve and the second sleeve to move synchronously away from the positioning sleeve. The bottom side of the inner cavity of the first sleeve abuts against and compresses the second spring, and the second sleeve abuts against and compresses the third spring. One end of the driven rod slides along the CD segment and falls into the DA segment.

[0035] Step E: The electric cylinder stops pushing the first sleeve and the second sleeve to move and resets. Under the elastic support of the second spring and the third spring, one end of the driven rod returns to point A along the DA segment, and the expanding pressure block is re-embedded into the positioning sleeve. Beneficial effects

[0036] (1) By using the guide rod to abut against the outer ring teeth of the sprocket, the elastic jump of the guide rod indirectly feeds back the jump status of the outer ring teeth of the sprocket. This not only reduces the influence of the surface roughness of the outer ring teeth of the sprocket on the accuracy of the laser displacement sensor, but also reduces the influence of the measurement distance, thereby increasing the accuracy of the laser displacement sensor in detecting the axial runout of the sprocket.

[0037] (2) The contact plate on the detection guide rod is driven by a single-axis driver to abut against the outer ring gear teeth of the sprocket. The laser receiving plate, as the laser receiving end, can prevent the detection guide rod from passing directly through the tooth groove and blocking the rotation of the sprocket, thus avoiding safety hazards. And through the compression or tension of the first spring, one end of the detection guide rod can maintain abutment against the outer ring gear of the sprocket, and the planar displacement of the laser receiving plate can accurately feed back the runout of the outer ring gear teeth of the sprocket.

[0038] (3) The expansion-diameter automatic telescopic locking clamp is driven to rotate by a stepper motor and a coupling, instead of manually cranking the handle to drive the sprocket to rotate. This ensures that the sprocket rotates at a uniform speed, while also reducing labor intensity and increasing efficiency.

[0039] (4) The electric cylinder drives the first sleeve to move and pulls the expansion drive rod through the adaptive adjustment function of the second spring, so that the expansion block expands outward while keeping the pressure between the expansion block and the sprocket within a certain range, so as to avoid the sprocket from generating residual stress due to excessive deformation.

[0040] (5) Through the self-locking structure between the driven rod and the closed-loop slide groove on the second sleeve, the one-way drive of the electric cylinder can meet the positioning, clamping, self-locking and release functions of the expanded diameter automatic telescopic locking fixture, reduce the time for picking up and putting down the sprocket and increase work efficiency. Attached Figure Description

[0041] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0042] Figure 1 This is a schematic diagram of the structure of the bicycle sprocket axial runout detection device in a preferred embodiment of the present invention;

[0043] Figure 2 This is a schematic diagram of the detection module in a preferred embodiment of the present invention;

[0044] Figure 3 This is a schematic diagram of the structure of the expanded diameter automatic telescopic locking clamp in a preferred embodiment of the present invention;

[0045] Figure 4 This is a lower view of the expanded diameter automatic telescopic locking clamp in a preferred embodiment of the present invention.

[0046] Figure 5 This is a preferred embodiment of the present invention. Figure 4 A schematic cross-sectional view at point AA;

[0047] Figure 6 This is a schematic diagram of the structure of the second sleeve in a preferred embodiment of the present invention;

[0048] Figure 7This is a schematic diagram of the positioning sleeve, the diameter expansion drive rod, and the diameter expansion pressure block in a preferred embodiment of the present invention;

[0049] Figure 8 This is a schematic diagram of the spatial motion path of the driven rod in a preferred embodiment of the present invention;

[0050] Figure 9 This is a schematic diagram of the planar motion path of the driven rod in a preferred embodiment of the present invention;

[0051] Figure 10 This is a schematic diagram of the operating logic of the bicycle sprocket axial runout detection device in a preferred embodiment of the present invention;

[0052] Figure 11 This is a schematic diagram of the control flow of the bicycle sprocket axial runout detection device in a preferred embodiment of the present invention;

[0053] The components include: 1. Frame; 2. Laser displacement sensor; 3. Sprocket; 301. Outer ring gear teeth; 4. Single-axis driver; 5. Fixed base; 6. Detection guide rod; 7. Laser receiving plate; 8. Limiting rod; 9. First spring; 10. Contact plate; 11. Reset button; 14. Stepper motor; 15. Combined sealing cover; 16. Positioning sleeve; 17. Expansion drive rod; 18. Expansion pressure block; 19. First sleeve; 20. Second spring; 21. Electric cylinder; 22. Second sleeve; 2201. Closed-loop slide groove; 23. Third spring; 24. Limiting post; 25. Driven rod; 26. Stop block; 27. Fourth spring. Detailed Implementation

[0054] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. These drawings are simplified schematic diagrams, which are only used to illustrate the basic structure of the present invention and therefore only show the components relevant to the present invention.

[0055] It should be noted that if directional indicators (such as up, down, bottom, top, etc.) are involved in this embodiment, these directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature. Unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances. Example 1

[0056] like Figures 1-3 As shown, a bicycle sprocket axial runout detection device includes a detection module mounted on a frame 1 and an expanded-diameter automatic telescopic locking clamp for fixing the sprocket 3. The detection module includes a laser displacement sensor 2 and a guide rod that can reciprocate along the laser beam path and serves as a laser receiver. The axial runout of the sprocket 3 is a flatness error. Currently, commonly used flatness error detection devices include dial indicators and laser sensors. Laser technology-based detection methods are non-contact measurements, offering advantages over dial indicators such as ease of use, high reliability, and no wear. The surface roughness of the workpiece and the measurement distance affect the accuracy of the displacement sensor. Therefore, by using the guide rod to abut against the outer ring teeth 301 of the sprocket 3, the elastic movement of the guide rod indirectly provides feedback on the runout of the outer ring teeth 301 of the sprocket 3. This not only reduces the impact of the surface roughness of the outer ring teeth 301 of the sprocket 3 on the accuracy of the laser displacement sensor 2 but also reduces the impact of the measurement distance. This increases the accuracy of the laser displacement sensor 2 in detecting the axial runout of the sprocket 3.

[0057] The detection module is located at the moving end of the single-axis driver 4. The single-axis driver 4 can drive the guide rod to elastically abut against the outer ring gear teeth 301. Using the single-axis driver 4 as the driving source for the overall movement of the detection module, the position, displacement speed, and displacement direction of the detection module can be precisely controlled. When axial runout detection of the sprocket 3 is required, the single-axis driver 4 can drive the entire detection module to move, causing one end of the guide rod to abut against the outer ring gear teeth 301 on the sprocket 3. When the axial runout detection of the sprocket 3 is completed, the single-axis driver 4 can drive the entire detection module to move in the opposite direction without affecting the placement and removal of the sprocket 3.

[0058] The expanded-diameter automatic telescopic locking fixture can be driven to rotate by a stepper motor 14. During the testing process, after the expanded-diameter automatic telescopic locking fixture positions and fixes the sprocket 3, it is driven to rotate by the stepper motor 14. In this technical solution, the stepper motor 14 can drive the expanded-diameter automatic telescopic locking fixture to rotate via a coupling, replacing the manual cranking of the handle to rotate the sprocket 3. This ensures that the sprocket 3 rotates at a uniform speed while reducing labor intensity and increasing efficiency. A bearing seat can also be fitted around the outer periphery of the expanded-diameter automatic telescopic locking fixture, connecting it to the frame 1 to ensure stable rotation of the fixture. The rotational motion of the expanded-diameter automatic telescopic locking fixture and the sprocket 3 has a significant impact on testing accuracy. Therefore, the bearing seat reduces frictional resistance during movement, improves transmission efficiency and equipment lifespan, and ensures rotational accuracy.

[0059] Furthermore, such as Figure 2As shown, the guide rod includes a fixed base 5 connected to the moving end of the single-axis driver 4, and a detection guide rod 6 slidably connected to the fixed base 5. The fixed base 5 is U-shaped, and the detection guide rod 6 passes through one side wall of the fixed base 5. A laser receiving plate 7 is provided at one end of the detection guide rod 6 facing the laser beam. The laser displacement sensor 2 is provided on the other side of the fixed base 5, and the laser beam emitted by it can pass through the side wall of the fixed base 5 and irradiate the laser receiving plate 7. The plane of the laser plate is perpendicular to the axis of the laser beam and the detection guide rod 6, and the displacement of the laser receiving plate 7 and the detection guide rod 6 are consistent. The laser receiving plate 7 is slidably sleeved on the outer periphery of a limiting rod 8 provided on the fixed base 5 and parallel to the detection guide rod 6, and a first spring 9 is also sleeved on the outer periphery of the limiting rod 8 and provided between the laser receiving plate 7 and the fixed base 5. The limiting rod 8 prevents the laser receiving plate 7 and the detection guide rod 6 from rotating and restricts the movement direction of the detection guide rod 6. Simultaneously, the first spring 9 provides elastic support between the fixed base 5 and the laser receiving plate 7. When the detection guide rod 6 abuts against the outer ring gear of the sprocket 3, the first spring 9 is compressed / stretched. During detection, one end of the detection guide rod 6 maintains abutment against the outer ring gear of the sprocket 3, allowing the displacement of the detection guide rod 6 to provide feedback on the movement of the outer ring gear of the sprocket 3. In this technical solution, if... Figure 2 As shown, the first spring 9 is fixedly connected at both ends to the side wall of the fixed base 5 through which the detection guide rod 6 passes and the laser receiving plate 7, respectively. When the detection guide rod 6 abuts against the outer ring gear of the sprocket 3, the first spring 9 is stretched. Alternatively, it can be directly sleeved on the outer circumference of the limiting rod 8 and elastically abut against the laser receiving plate 7 and the other side wall of the fixed base 5. When the detection guide rod 6 abuts against the outer ring gear of the sprocket 3, the first spring 9 is compressed.

[0060] A contact plate 10 is provided at one end of the detection guide rod 6 that can abut against the outer ring gear teeth 301. The length of the contact plate 10 is greater than the distance between two adjacent outer ring gear teeth 301 on the sprocket 3. This prevents the detection guide rod 6 from passing directly through the tooth groove between two gear teeth, thus blocking the rotation of the sprocket 3 and causing a safety hazard.

[0061] In this embodiment, the frame 1 is equipped with a reset button 11 that is signal-connected to the single-axis driver 4 and the stepper motor 14. By pressing the reset button 11, the single-axis driver 4 can be driven to drive the detection module to perform the set steps, or the stepper motor 14 can be driven to perform the set steps, move to the set position, and wait for the next action. Example 2

[0062] like Figures 1-7As shown, based on Embodiment 1, an expanding-diameter automatic telescopic locking clamp includes an expanding-diameter tensioning mechanism, an automatic telescopic locking mechanism, and a combined sealing cover 15 covering the outer periphery of the expanding-diameter tensioning mechanism and the automatic telescopic locking mechanism. The combined sealing cover 15 is a split structure and can be fixed by bolt connection, which facilitates the installation and maintenance of the expanding-diameter tensioning mechanism and the automatic telescopic locking mechanism. The combined sealing cover 15 is hollow tubular in shape and has a slot on its outer periphery, so that part of the structure of the first sleeve 19 and the second sleeve 22 extends out from the combined sealing cover 15 and abuts against the telescopic end of the electric cylinder 21 when the electric cylinder 21 is actuated.

[0063] The expansion and tightening mechanism includes a positioning sleeve 16 disposed at the end of the combined sealing cover 15, an expansion drive rod 17 slidably embedded in the positioning sleeve 16 at one end, and several expansion pressure blocks 18 slidably sleeved on the expansion drive rod 17 and slidably embedded on the positioning sleeve 16. In this technical solution, there are two expansion pressure blocks 18, which are slidably disposed on the expansion drive rod 17. The diameter of a section of the positioning sleeve 16 gradually increases from its end to its root to facilitate insertion and engagement with the sprocket 3. Since the spatial position of the sprocket 3 in the detection device affects the accuracy of the detection results, and the sprocket 3 has six degrees of freedom in space—three axial directions of translational and rotational freedom in a Cartesian coordinate system—this technical solution selects a positioning method of combining a square shaft with a small end face to form the positioning sleeve 16. Unlike ordinary long cylindrical pins, the square shaft can also restrict the rotational freedom of the sprocket 3 in the X-axis direction, serving as a dedicated positioning element for the sprocket 3. The small end face can restrict one degree of freedom, namely the movement degree of the sprocket 3 in the X-axis direction, while the square shaft can constrain the other five degrees of freedom. Therefore, all six degrees of freedom of the sprocket 3 part are constrained. When the sprocket 3 workpiece is fixed by the positioning sleeve 16 and the expansion pressure block 18, it is in a fully positioned state.

[0064] In this technical solution, the sliding groove structure is used by the expansion drive rod 17 to drive the expansion pressure block 18 to move radially and abut against the inner wall of the square hole on the sprocket 3. The sliding groove structure includes a groove inclinedly disposed on the expansion pressure block 18, and a protrusion inclinedly disposed on the expansion drive rod 17 and slidingly engaged with the groove. The positioning sleeve 16 is fixed to the combined sealing cover 15 by bolts, and its position is fixed. Figure 7 As shown, the front and rear ends of the expanding pressure block 18 are restricted by the positioning sleeve 16, and the vertical displacement is restricted by the protrusion. The expanding pressure block 18 and the expanding drive rod 17 form a sliding groove mechanism through the groove and the protrusion. It can only slide radially under the drive of the expanding drive rod 17. Furthermore, one end of the expanding drive rod 17 is embedded in the positioning sleeve 16, and the other end passes through the positioning sleeve 16 and is placed in the combined sealing cover 15.

[0065] The outer periphery of the expansion drive rod 17 is fitted with a first sleeve 19 that is slidably connected within the combined sealing cover 15, such as... Figure 5 As shown, a second spring 20 is provided between the first sleeve 19 and the expansion drive rod 17, sleeved on the outer periphery of the expansion drive rod 17. The two ends of the second spring 20 abut against the bottom side of the inner cavity of the first sleeve 19 and the nail-shaped post on the expansion drive rod 17, respectively. The expansion drive rod 17 and the first sleeve 19 are clearance-fitted, which can compensate for errors generated during processing and assembly. The second spring 20 in the middle has an adaptive adjustment function, such as... Figure 5 As shown, when the first sleeve 19 moves to one side, it will compress the second spring 20. The elastic force of the second spring 20 will also act on the expansion drive rod 17, causing the expansion drive rod 17 to move, thereby driving the expansion pressure block 18 to extend out from the positioning sleeve 16 and press against the side wall of the square hole on the sprocket 3. Within the compression range of the second spring 20, part of the force exerted by the first sleeve 19 on the expansion drive rod 17 through the second spring 20 will be converted into the compression elastic force of the second spring 20. The force between the expansion pressure block 18 and the sprocket 3 will be limited to a certain range, which can prevent the sprocket 3 from generating residual stress due to excessive deformation.

[0066] The automatic telescopic locking mechanism includes an electric cylinder 21 that can push the first sleeve 19 to move. The telescopic end of the electric cylinder 21 can abut against the first sleeve 19 to drive the first sleeve 19 to move to one side.

[0067] Furthermore, such as Figure 3 , Figure 4 , Figure 5 As shown, the automatic telescopic locking mechanism also includes a second sleeve 22 disposed inside the combined sealing cover 15, opposite to the first sleeve 19, and capable of moving synchronously. The first sleeve 19 and the second sleeve 22 can be connected as a whole by bolts. A third spring 23 is disposed between the second sleeve 22 and the inner cavity side wall of the combined sealing cover 15. The third spring 23 is sleeved on the outer periphery of the limiting post 24 placed on the inner cavity side wall of the combined sealing cover 15. When the first sleeve 19 is pushed to move by the electric cylinder 21, the second sleeve 22 moves synchronously with the first sleeve 19. The second spring 20 sleeved on the outer periphery of the expansion drive rod 17 and the third spring 23 sleeved on the outer periphery of the limiting post 24 are both compressed. The limiting post 24 can limit the direction of the compression deformation of the third spring 23, so that the elastic force of the third spring 23 is stably supported between the second sleeve 22 and the combined sealing cover 15.

[0068] When the electric cylinder 21 pushes the first sleeve 19 to move, the third spring 23 is compressed, providing power for the second sleeve 22 to reset; the second sleeve 22 is provided with a closed-loop sliding groove 2201, and the other end of the combined sealing cover 15 is provided with a driven rod 25.

[0069] The driven rod 25 is L-shaped. One end of the driven rod 25 is rotatably connected to the combined sealing cover 15 and can move up and down along the axis of that end. The other end can slide along the closed-loop groove 2201. The main function of the automatic telescopic locking mechanism is to drive the expansion drive rod 17 to move, so that the shaft diameter of the positioning sleeve 16 expands and contracts through the expansion pressure block 18, thereby clamping the sprocket 3, and can achieve self-locking at a specific position. One end of the driven rod 25 that slides along the closed-loop groove 2201 can abut against the side wall of the closed-loop groove 2201, and as the positions of the first sleeve 19 and the second sleeve 22 change, the position of the end of the driven rod 25 in the closed-loop groove 2201 also changes accordingly. Similarly, when the end of the driven rod 25 slides along the closed-loop groove 2201, the positions of the first sleeve 19 and the second sleeve 22 on the combined sealing cover 15 also change accordingly. When the driven rod 25 stops at a certain point in the closed-loop groove 2201, the first sleeve 19 and the second sleeve 22 will also maintain a certain fixed state without the influence of external force, that is, the first sleeve 19 and the second sleeve 22 are self-locking.

[0070] In the above technical solution, to drive the first sleeve 19 and the second sleeve 22 to self-lock at a certain position by the electric cylinder 21, and also to drive the first sleeve 19 and the second sleeve 22 to unlock by the same electric cylinder 21, the closed-loop slide groove 2201 includes sections AB, BC, CD, and DA. In this technical solution, for ease of understanding the structure of the closed-loop slide groove 2201, as follows... Figure 8 , Figure 9 As shown, points A, B, C, and D are set on the closed-loop slide 2201. Segment AB is the section between points A and B on the closed-loop slide 2201 that does not pass through any other points in the middle. Segment BC is the section between points B and C on the closed-loop slide 2201 that does not pass through any other points in the middle. Segment CD is the section between points C and D on the closed-loop slide 2201 that does not pass through any other points in the middle. Segment DA is the section between points D and A on the closed-loop slide 2201 that does not pass through any other points in the middle. Figure 8In the diagram, the external force driving path is the path along which the end of the driven rod 25 moves within the closed-loop slide groove 2201 when the electric cylinder 21 drives the first sleeve 19 and the second sleeve 22 to move; the elastic force driving path is the path along which the end of the driven rod 25 moves within the closed-loop slide groove 2201 when the electric cylinder 21 is reset and the third spring 23 drives the second sleeve 22 to move; the height change path is the path along which the end of the driven rod 25 changes height within the closed-loop slide groove 2201. The high step surface, the middle step surface, and the low step surface are step surfaces of different heights on the three closed-loop slide grooves 2201.

[0071] Specifically, the core of the self-locking device is to control the end of the driven rod 25 to move along a set path, and when it reaches a specific position, the driven rod 25 and the closed-loop slide 2201 mutually restrain each other and lock it in place. The movement path in this technical solution refers to the distance traveled by the driven rod 25 relative to the closed-loop slide 2201, which is a closed-loop structure in three-dimensional space. Accordingly, the AB segment is divided into a first segment, a second segment, and a third segment. The second segment is an ascending gentle slope. The depth of the groove in the first segment is higher than the depth of the groove in the third segment. The groove depth of the third segment is equal to that of the BC segment. The depth of the groove in the DA segment is between the depths of the BC segment and the groove in the first segment, and a stepped surface is provided at the junction. A stop 26 is formed on the second sleeve 22 by the closed-loop slide 2201.

[0072] In this technical solution, the closed-loop slide 2201 has three stepped surfaces of different heights. The change in step height controls the driven rod 25 to move in a closed loop along the ABCDA direction. In this technical solution, the BC segment and the CD segment are connected to form a V-shape, and the overall closed-loop slide 2201 has a heart-shaped racetrack-like closed-loop structure. Figure 8 The diagram shows the spatial movement path of the driven rod 25. During its sliding process, the driven rod 25 passes through three stepped surfaces: low, high, and medium. A linear transition plane exists between the low and high stepped surfaces. When the end of the driven rod 25 is at point D, it is limited by the height of the stepped surfaces and can only slide along segment DA to point A. Similarly, when the end of the driven rod 25 is at point A, it can only slide along segment AB to point B. At point B, the structural center of the end of the driven rod 25 is within the range of the stop block 26. Therefore, the electric cylinder 21 resets, and the third spring 23, under its elastic support, pushes the second sleeve 22 to one side. The end of the driven rod 25 hits the stop block 26 and then moves along the edge of the stop block 26 to point C. The movement from point C to point D follows the same principle, thus completing one unidirectional cycle of motion for the driven rod 25.

[0073] When the end of the driven rod 25 is at point C, the second sleeve 22 is subjected to the axial force of the third spring 23. Since the rotating section of the driven rod 25 is rotatably connected to the combined sealing cover 15, it can abut against the side wall of the closed-loop slide groove 2201, forming a pair of mutually restraining balanced forces. As long as it is not affected by other external forces, the end of the driven rod 25 can be locked at the position of point C.

[0074] Furthermore, a section of the driven rod 25 rotatably connected to the combined sealing cover 15 passes through the combined sealing cover 15, and a fourth spring 27 is sleeved on its outer periphery. The two ends of the fourth spring 27 abut against the outer periphery of the combined sealing cover 15 and the nail-shaped post head of that section of the driven rod 25, respectively. Figure 5 As shown, the fourth spring 27 provides a continuous downward elastic force to the driven rod 25, and the driven rod 25 as a whole has a tendency to move in only one direction. Therefore, no matter how the height of the step surface inside the closed-loop slide groove 2201 changes, the end of the driven rod 25 can always maintain effective and tight contact with the bottom side of the closed-loop slide groove 2201. At the same time, in this technical solution, both ends of the fourth spring 27 can also be fixedly connected to the driven rod 25 and the combined sealing cover 15 respectively, performing the function of a torsion spring. When the end of the driven rod 25 slides along the closed-loop slide groove 2201, the driven rod 25 can be assisted to rotate only clockwise or counterclockwise by the angular energy and rotational force stored in the fourth spring 27 without the action of other external forces. Example 3

[0075] like Figure 10-11 As shown, based on Embodiment 1 and Embodiment 2, a control method for a bicycle sprocket axial runout detection device includes the following steps:

[0076] Step 1: Press the reset button 11. The single-axis driver 4 drives the detection module to the initial position, and the stepper motor 14 drives the expanded-diameter automatic telescopic locking fixture to the original position. The initial position of the detection module does not affect the installation and removal of the sprocket 3. That is, when the sprocket 3 is fixedly installed on or removed from the expanded-diameter automatic telescopic locking fixture, the detection guide rod 6 on the detection module should not elastically abut against the outer ring teeth 301 of the sprocket 3. Its specific position can be customized. For example... Figure 1 As shown, the original position of the expanding-diameter automatic telescopic locking clamp is that the part of the first sleeve 19 extending from the combined sealing cover 15 is rotated to a position that can abut against the telescopic end of the electric cylinder 21. At this time, the electric cylinder 21 is in the retracted state. In this technical solution, the positions of the first sleeve 19 and the second sleeve 22 can be detected by photoelectric sensors. When the stepper motor 14 drives the expanding-diameter automatic telescopic locking clamp to rotate, so that the first sleeve 19 and the second sleeve 22 can abut against the telescopic end of the electric cylinder 21, the photoelectric sensor will transmit a signal to the electric cylinder 21, and the electric cylinder 21 will execute the corresponding command to drive the telescopic end to abut against the first sleeve 19.

[0077] Step 2: The sprocket 3 is manually fitted onto the outer periphery of the positioning sleeve 16. After the electric cylinder 21 drives the expanded diameter automatic telescopic locking clamp to perform the first corresponding control operation, it is reset, positioning and fixing the position of the sprocket 3.

[0078] Step 3: The single-axis driver 4 drives the detection module to move toward the direction of the sprocket 3 until the laser displacement sensor 2 detects a change in distance. The single-axis driver 4 then stops advancing, indicating that the contact plate 10 has pressed against the teeth of the sprocket 3.

[0079] Step 4: The laser displacement sensor 2 sets the plane at this time as the detection reference plane, starts the stepper motor 14 to drive the expanded diameter automatic telescopic locking fixture and the sprocket 3 to rotate, and the detection begins. The stepper motor 14 rotates a preset number of times and then stops. The laser displacement sensor 2 collects data and uploads it for analysis. The preset number of rotations is the set number of rotations that the stepper motor 14 drives the expanded diameter automatic telescopic locking fixture to rotate.

[0080] Step 5: After the stepper motor 14 stops driving, the single-axis driver 4 resets, and the electric cylinder 21 drives the expanding-diameter automatic telescopic locking fixture to perform the second corresponding control operation and then resets, releasing and removing the sprocket 3, completing one test.

[0081] Furthermore, in the above technical solution, the specific steps for resetting the electric cylinder 21 after driving the expanded-diameter automatic telescopic locking clamp to perform the first corresponding control operation include:

[0082] Step A: The electric cylinder 21 pushes the first sleeve 19 and the second sleeve 22 to move synchronously away from the positioning sleeve 16. The bottom side of the inner cavity of the first sleeve 19 abuts against and compresses the second spring 20, and the second sleeve 22 abuts against and compresses the third spring 23. One end of the driven rod 25 slides along the AB segment. Then, the first sleeve 19 pulls the expansion drive rod 17 to move in the same direction through the third spring 23. The expansion pressure block 18 gradually abuts against the inner wall of the square hole on the sprocket 3, positioning and fixing the position of the sprocket 3.

[0083] Step B; The electric cylinder 21 stops pushing the first sleeve 19 and the second sleeve 22 to move, and resets;

[0084] Step C: The third spring 23 rebounds, the first sleeve 19 and the second sleeve 22 move in opposite directions, and one end of the driven rod 25 moves along the BC segment until it falls into point C, completing the self-locking.

[0085] Furthermore, in the above technical solution, the specific steps for resetting the electric cylinder 21 after driving the expanded-diameter automatic telescopic locking clamp to perform a second corresponding control operation include:

[0086] Step D: The electric cylinder 21 pushes the first sleeve 19 and the second sleeve 22 to move synchronously away from the positioning sleeve 16. The bottom side of the inner cavity of the first sleeve 19 abuts against and compresses the second spring 20, and the second sleeve 22 abuts against and compresses the third spring 23. One end of the driven rod 25 slides along the CD segment and falls into the DA segment.

[0087] Step E: The electric cylinder 21 stops pushing the first sleeve 19 and the second sleeve 22 to move and resets. Under the elastic support of the second spring 20 and the third spring 23, one end of the driven rod 25 returns to point A along the DA segment, and the expanding pressure block 18 is re-embedded into the positioning sleeve 16.

[0088] Working Principle: This technical solution employs an indirect axial runout detection method for sprocket 3 based on laser technology, using a laser displacement sensor 2 to replace the gear transmission system in the dial indicator. Finally, the laser displacement sensor 2 and the guide rod are integrated into a detection module. The module indirectly feeds back the vibration generated when the guide rod 6 comes into contact with the outer ring gear of the rotating sprocket 3. This not only makes the entire device more compact and easier to install, but also avoids the surface roughness of the sprocket 3 affecting the accuracy of the runout detection.

[0089] Meanwhile, through radial clamping, the expansion and contraction of the expansion block 18 on the expansion and tightening mechanism driven by the electric cylinder 21 can quickly clamp and release the sprocket 3. The automatic telescopic locking mechanism drives the expansion drive rod 17 to move, causing the expansion block 18 to expand outward and increase its shaft diameter, thereby clamping the sprocket 3. It can also complete self-locking and release at specific positions, which greatly increases the working efficiency of the bicycle sprocket axial runout detection device.

[0090] Based on the preferred embodiments of the present invention described above, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A bicycle sprocket axial runout detection device, characterized in that: It includes a detection module mounted on a frame (1) and an expanded diameter automatic telescopic locking clamp for fixing a sprocket (3). The detection module includes a laser displacement sensor (2) and a guide rod that can reciprocate along the laser beam path and serves as a laser receiver. The detection module is located at the moving end of the single-axis driver (4), and the single-axis driver (4) can drive the guide rod to elastically abut against the outer ring gear teeth (301); The expanded diameter automatic telescopic locking clamp can be driven to rotate by a stepper motor (14). The expanded diameter automatic telescopic locking clamp includes an expanded diameter tightening mechanism, an automatic telescopic locking mechanism, and a combined sealing cover (15) covering the outer periphery of the expanded diameter tightening mechanism and the automatic telescopic locking mechanism. The expansion and tightening mechanism includes a positioning sleeve (16) disposed at the end of the combined sealing cover (15), an expansion drive rod (17) with one end slidably embedded in the positioning sleeve (16), and a plurality of expansion pressure blocks (18) respectively slidably sleeved on the expansion drive rod (17) and slidably embedded on the positioning sleeve (16). A groove structure is provided between the expansion drive rod (17) and the expansion pressure block (18). The outer periphery of the expansion drive rod (17) is fitted with a first sleeve (19) that is slidably connected inside the combined sealing cover (15). A second spring (20) is provided between the first sleeve (19) and the expansion drive rod (17) and fitted on the outer periphery of the expansion drive rod (17). The two ends of the second spring (20) abut against the bottom side of the inner cavity of the first sleeve (19) and the nail-shaped column head on the expansion drive rod (17), respectively. The automatic telescopic locking mechanism includes an electric cylinder (21) that can push the first sleeve (19) to move. The automatic telescopic locking mechanism also includes a second sleeve (22) that is disposed inside the combined sealing cover (15) and is opposite to the first sleeve (19) and can move synchronously. A third spring (23) is disposed between the second sleeve (22) and the inner cavity sidewall of the combined sealing cover (15). The third spring (23) is sleeved on the outer periphery of the limiting post (24) placed on the inner cavity sidewall of the combined sealing cover (15). When the electric cylinder (21) pushes the first sleeve (19) to move, the third spring (23) is compressed, providing power for the second sleeve (22) to reset; the second sleeve (22) is provided with a closed-loop slide groove (2201), and the other end of the combined sealing cover (15) is provided with a driven rod (25). The driven rod (25) is L-shaped. One section of the driven rod (25) is rotatably connected to the combined sealing cover (15) and can move up and down along the axis of that section. The end of the other section can slide along the closed-loop groove (2201). The closed-loop slide (2201) includes sections AB, BC, CD, and DA; The AB section is divided into a first section, a second section, and a third section. The second section is a gentle upward slope. The depth of the groove where the first section is located is higher than the depth of the groove where the third section is located. The groove depth of the third section is equal to that of the BC section. The depth of the groove where the DA section is located is between the depths of the grooves where the BC section and the first section are located. A stepped surface is provided at the junction. A stop block (26) is formed on the second sleeve (22) by means of the closed-loop sliding groove (2201).

2. The bicycle sprocket axial runout detection device according to claim 1, characterized in that: The guide rod includes a fixed seat (5) connected to the moving end of the single-axis driver (4) and a detection guide rod (6) slidably connected to the fixed seat (5). A laser receiving plate (7) is provided at one end of the detection guide rod (6) facing the laser beam. The laser receiving plate (7) is slidably sleeved on the outer periphery of a limiting rod (8) provided on the fixed seat (5) and parallel to the detection guide rod (6). A first spring (9) is also sleeved on the outer periphery of the limiting rod (8) and provided between the laser receiving plate (7) and the fixed seat (5). A contact plate (10) is provided on one end of the detection guide rod (6) that can abut against the outer ring gear teeth (301). The length of the contact plate (10) is greater than the distance between two adjacent outer ring gear teeth (301) on the sprocket (3).

3. The bicycle sprocket axial runout detection device according to claim 2, characterized in that: The frame (1) is equipped with a reset button (11) that is connected to the single-axis driver (4) and the stepper motor (14).

4. The bicycle sprocket axial runout detection device according to claim 3, characterized in that: The driven rod (25) is rotatably connected to the combined sealing cover (15) through the combined sealing cover (15), and a fourth spring (27) is sleeved on its outer periphery. The two ends of the fourth spring (27) abut against the outer periphery of the combined sealing cover (15) and the nail-shaped column head on the driven rod (25) of that section, respectively.

5. The control method for the bicycle sprocket axial runout detection device according to claim 4, characterized in that, Includes the following steps: Step 1: Press the reset button (11), the single-axis driver (4) drives the detection module to move to the initial position, and the stepper motor (14) drives the expanded diameter automatic telescopic locking fixture to rotate to the original position; Step 2: The sprocket (3) is manually placed on the outer circumference of the positioning sleeve (16). The electric cylinder (21) drives the expanded diameter automatic telescopic locking clamp to perform the first corresponding control operation and then resets, positioning and fixing the position of the sprocket (3). Step 3: The single-axis driver (4) drives the detection module to move toward the direction of the sprocket (3) until the laser displacement sensor (2) detects a change in distance, and the single-axis driver (4) stops advancing. Step 4: The laser displacement sensor (2) sets the plane at this time as the detection reference plane, starts the stepper motor (14) to drive the expanded diameter automatic telescopic locking fixture and the sprocket (3) to rotate, the detection begins, the stepper motor (14) rotates a preset number of times and then stops, the laser displacement sensor (2) collects data and uploads it for analysis; Step 5: After the stepper motor (14) stops driving, the single-axis driver (4) is reset, and the electric cylinder (21) drives the expanded diameter automatic telescopic locking fixture to perform the second corresponding control operation and then resets, releases and removes the sprocket (3), and completes one test.

6. The bicycle sprocket axial runout detection device and control method according to claim 5, characterized in that, The specific steps for resetting the electric cylinder (21) after driving the expanded-diameter automatic telescopic locking clamp to perform the first corresponding control operation include: Step A: The electric cylinder (21) pushes the first sleeve (19) and the second sleeve (22) to move synchronously away from the positioning sleeve (16). The bottom side of the inner cavity of the first sleeve (19) abuts against and compresses the second spring (20), and the second sleeve (22) abuts against and compresses the third spring (23). One end of the driven rod (25) slides along the AB segment. Then the first sleeve (19) pulls the expansion drive rod (17) to move in the same direction through the third spring (23). The expansion pressure block (18) gradually abuts against the inner wall of the square hole on the sprocket (3), positioning and fixing the position of the sprocket (3). Step B; The electric cylinder (21) stops pushing the first sleeve (19) and the second sleeve (22) to move, and resets; Step C: The third spring (23) rebounds, the first sleeve (19) and the second sleeve (22) move in opposite directions, and one end of the driven rod (25) moves along the BC segment until it falls into point C, thus completing the self-locking.

7. The control method for the bicycle sprocket axial runout detection device according to claim 5, characterized in that, The specific steps for resetting the electric cylinder (21) after driving the expanded-diameter automatic telescopic locking clamp to perform the second corresponding control operation include: Step D; The electric cylinder (21) pushes the first sleeve (19) and the second sleeve (22) to move synchronously away from the positioning sleeve (16). The bottom side of the inner cavity of the first sleeve (19) abuts against and compresses the second spring (20), and the second sleeve (22) abuts against and compresses the third spring (23). One end of the driven rod (25) slides along the CD segment and falls into the DA segment. Step E: The electric cylinder (21) stops pushing the first sleeve (19) and the second sleeve (22) to move and resets. Under the elastic support of the second spring (20) and the third spring (23), one end of the driven rod (25) returns to point A along the DA segment, and the expansion block (18) is re-embedded into the positioning sleeve (16).

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