A quartz tube coaxiality measuring device

Abstract

The application discloses a quartz tube coaxiality measuring device and relates to the technical field of laser measuring instruments, which comprises a fixing assembly, a laser layout assembly and a tube wall adapting assembly. The fixing assembly comprises a rack and a chuck rotatably connected to the top of the rack. The laser layout assembly comprises a rotating shaft rotatably connected to the side of the rack, two swing arms fixedly connected to the upper and lower ends of the rotating shaft, and a transmitter and a receiver fixedly installed at one end of the two swing arms, respectively. The tube wall adapting assembly comprises a linear module fixedly installed on the side of the rack and a hollow tube rotatably connected to the sliding block of the linear module. The application forms a "dynamic optical shutter" through the laser beam and the variable-diameter light hole. The receiver converts the optical signal into an electrical signal, and the real-time determination of whether the coaxiality is qualified is realized. The design realizes that the laser does not directly irradiate the quartz tube, completely avoids the influence of the projection, reflection and refraction of light on the detection, and has the advantages of simple structure, low cost and rapid detection.

Description

Technical Field

[0001] This invention relates to the field of laser measuring instrument technology, and more specifically, to a quartz tube coaxiality measuring device. Background Technology

[0002] Quartz tubes, due to their high light transmittance, strong chemical stability, and excellent insulation properties, are widely used in various fields. For example, in the semiconductor industry, quartz tubes serve as core components such as diffusers and oxide tubes. Their coaxiality directly affects the stability of high-temperature processes. Transparent quartz glass tubes for semiconductors must meet strict requirements for ellipticity and wall deviation. If the coaxiality deviation is too large, it will lead to uneven distribution of high-temperature gases inside the tube, affecting the uniformity of chip doping or oxide layers, ultimately reducing chip performance. Similarly, in side-pumped high-power laser equipment, the quartz tube must be coaxially fitted with the laser crystal rod. The coaxiality of the two determines the uniformity of the cooling channels. A high-reflectivity coating on the outer surface of the quartz tube can reflect residual pump light back to the laser crystal. Insufficient coaxiality will lead to increased optical loss or decreased laser beam quality.

[0003] Laser measurement of the coaxiality of quartz tubes (i.e., the coincidence of the inner and outer circular axes) has become a mainstream technology for precision testing of quartz tubes due to its advantages such as non-contact operation, high precision (down to the micrometer or even nanometer level), and fast response. It utilizes a laser collimator to generate a high-precision reference straight line (simulating an ideal axis). Laser displacement sensors (such as laser triangulation sensors) are placed at both ends or multiple cross-sections of the quartz tube to simultaneously detect the radial deviation of the inner and outer walls from the reference axis. Specifically, the quartz tube is placed on a rotating platform, and the sensors collect real-time distance data between the inner and outer walls at different angles during rotation. By fitting the coordinates of the centers of the inner and outer circles, the deviation of its axis from the reference laser axis is calculated, ultimately yielding the coaxiality error. This coaxiality error is used to determine whether the measured quartz tube meets the coaxiality requirements. However, this technology also has certain drawbacks: the transparent material of the quartz tube, with its reflection, projection, and refraction characteristics of laser light, can interfere with the stable transmission and reception of the laser, leading to poor measurement accuracy. Often, expensive or complex equipment is required to counteract this effect.

[0004] To address the aforementioned issues, a quartz tube coaxiality measuring device is proposed. Summary of the Invention

[0005] To solve the above-mentioned technical problems, a quartz tube coaxiality measuring device is provided, which solves the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention can be implemented using the following technical solutions:

[0007] This invention provides a quartz tube coaxiality measuring device, comprising:

[0008] The fixed assembly includes a frame and a chuck rotatably connected to the top of the frame;

[0009] The laser deployment assembly includes a rotating shaft rotatably connected to the side of the frame, two swing arms fixedly connected to the upper and lower ends of the rotating shaft, and a transmitter and a receiver respectively fixedly installed at one end of the two swing arms.

[0010] The tube wall adapter assembly includes a linear module fixedly mounted on the side of the frame, a support block fixedly mounted on the slider of the linear module, a hollow tube rotatably connected to the support block and fixedly sleeved outside the rotating shaft, a follower arm fixedly connected to the hollow tube, a short arm fixedly connected to one side of the hollow tube, and a spring fixedly connected to the side of the short arm facing the slider, the other end of the spring being fixedly connected to the slider of the linear module.

[0011] The calibration measurement component includes a second motor fixedly mounted on one end of the follower arm, a turntable fixedly mounted on the drive shaft of the second motor, and multiple light-transmitting holes evenly opened on the turntable along the circumferential direction. The diameter of each light-transmitting hole gradually increases, and the diameter of the smallest light-transmitting hole is consistent with the diameter of the laser beam. The center of each light-transmitting hole is located on a concentric circle on the turntable.

[0012] Furthermore, the chuck's axis is vertical, the rotating shaft is vertically set, and the laser beam emitted by the transmitter is vertical.

[0013] Furthermore, the fixing assembly also includes a motor that is fixedly mounted on the top of the frame, and the drive shaft of the motor is fixedly connected to the chuck.

[0014] Furthermore, the laser deployment assembly also includes a servo motor fixedly mounted on the frame, with the drive shaft of the servo motor fixedly connected to the bottom end of the rotating shaft.

[0015] Furthermore, the pipe wall adapter assembly also includes a support arm 1 fixedly connected to the side of the slider of the linear module, and an electromagnetic push rod 1 for pushing the short arm 1 is fixedly installed at one end of the support arm 1.

[0016] Furthermore, the quartz tube coaxiality measuring device also includes a compensation component, which includes a short shaft rotatably connected to the slider of the linear module, a support arm fixedly connected to the middle of the short shaft, a second short arm fixedly connected to one side of the short shaft, and a second spring fixedly connected to the side of the second short arm facing the slider. The other end of the second spring is fixedly connected to the slider of the linear module. The support arm and the follower arm have the same structure and are symmetrically arranged about the axis of the chuck.

[0017] Furthermore, the offsetting component also includes a second support arm fixedly connected to the side of the slider of the linear module, and an electromagnetic push rod for pushing the second short arm is fixedly installed at one end of the second support arm.

[0018] As described above, the beneficial effects of the quartz tube coaxiality measuring device of the present invention are as follows:

[0019] A fixed-diameter laser beam and a variable-diameter light-transmitting aperture form a "dynamic shutter". When the displacement of the follower arm sliding against the surface of the quartz tube exceeds ΔR, that is, when the measured coaxiality of the quartz tube exceeds the specified threshold, the edge of the light-transmitting aperture will block the laser beam. Finally, the receiver converts the optical signal into an electrical signal and issues an alarm, realizing real-time judgment of whether the coaxiality is qualified. This design achieves that the laser does not directly irradiate the quartz tube, completely avoiding the influence of light projection, reflection and refraction on the detection. At the same time, the structure is simple and the cost is low, avoiding the shortcomings of the existing technology.

[0020] The support arm and the follower arm are arranged symmetrically, and the net lateral force is close to zero, which eliminates lateral contact force deformation and avoids deformation of the quartz tube due to contact force. This ensures that the detection deviation is the coaxiality error of the tube itself. The vertical suspension also eliminates the radial deformation caused by gravity. The two work together to further reduce the detection error. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0022] Figure 2 for Figure 1 A schematic diagram of the structure from another perspective;

[0023] Figure 3 This is a schematic diagram of the laser deployment assembly and other components shown in this invention;

[0024] Figure 4 This is a schematic diagram of the pipe wall adaptation component and calibration measurement component shown in this invention;

[0025] Figure 5 for Figure 4 A schematic diagram of the structure from another perspective;

[0026] Figure 6 This is a schematic diagram of the offsetting components and other parts shown in this invention;

[0027] Figure 7 for Figure 1 Enlarged structural diagram at point A;

[0028] Figure 8 This is a schematic diagram of the structure of the present invention from a low-angle view.

[0029] The reference numerals in the accompanying drawings of this invention are as follows:

[0030] Fixed components: 11. Frame; 12. Chuck; 13. Motor 1;

[0031] Laser deployment components: 21. Rotary shaft; 22. Swing arm; 23. Transmitter; 24. Receiver; 25. Servo motor;

[0032] Pipe wall adapter components: 31. Linear module; 32. Hollow tube; 33. Follower arm; 34. Short arm one; 35. Spring one; 36. Electromagnetic push rod one; 37. Support arm one;

[0033] Calibration and measurement components: 41. Motor II; 42. Turntable; 43. Light transmission hole;

[0034] Counteracting components: 51. Short shaft; 52. Support arm; 53. Second short arm; 54. Second spring; 55. Second electromagnetic push rod; 56. Second support arm. Detailed Implementation

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0036] See Figures 1-8 As shown, this is an embodiment of the present invention, and the provided quartz tube coaxiality measuring device will be described in detail below.

[0037] A quartz tube coaxiality measuring device, comprising:

[0038] Fixed components, see Figures 1-3 As shown, it includes a frame 11 and a chuck 12 rotatably connected to the top of the frame 11. The chuck 12 rotates around the Z-axis (that is, around the vertical line). Furthermore, the fixing assembly also includes a motor 13 fixedly installed at the top of the frame 11. The drive shaft of the motor 13 is fixedly connected to the chuck 12, and the motor 13 can drive the chuck 12 to rotate.

[0039] It should be noted that the chuck 12 adopts existing technology and is a common lathe device. Specifically, in this embodiment, in order to adapt to the clamping and fixing of the quartz tube, it is required that the jaw part of the chuck 12 does not cause scratches or other damage to the quartz tube. Therefore, in this embodiment, the material of the jaw, or the material used for the part of the jaw in contact with the quartz tube, is preferably one of polytetrafluoroethylene (PTFE, commonly known as "Teflon"), ultra-high molecular weight polyethylene (UHMWPE), or pure copper (red copper, T2 state), or other similar materials.

[0040] Furthermore, in this embodiment, the arrangement of the chuck 12 is intentionally set to rotate around a vertical line. The purpose is to avoid gravitational interference when the quartz tube is vertically suspended. That is, the top of the quartz tube is clamped by the chuck 12 to form a single-point vertical suspension state. At this time, the direction of gravity is parallel to the axis of the tube body, and there is no radial deflection. The axis of the quartz tube is completely coincident with the direction of gravity. Gravity will only generate tensile stress in the axial direction, rather than a radial force that causes it to bend. It also avoids the situation in the prior art where uneven clamping force caused by multiple supports leads to local bending of the quartz tube and affects the state of the quartz tube itself, making the internal stress of the quartz tube simple and uniform.

[0041] The quartz tube coaxiality measuring device also includes a laser deployment assembly, see [link / reference]. Figures 1-4 As shown, the laser deployment assembly includes a rotating shaft 21 rotatably connected to the side of the frame 11, two swing arms 22 fixedly connected to the upper and lower ends of the rotating shaft 21, and a transmitter 23 and a receiver 24 respectively fixedly installed at one end of the two swing arms 22. The rotating shaft 21 is vertically arranged, and the laser beam emitted by the transmitter 23 is in a vertical state. Furthermore, the laser deployment assembly also includes a servo motor 25 fixedly installed below the frame 11, and the drive shaft of the servo motor 25 is fixedly connected to the bottom end of the rotating shaft 21.

[0042] It should be noted that the transmitter 23 and receiver 24 are existing laser emitting and receiving devices. The transmitter 23 emits colored laser light, such as red. In this embodiment, since the quartz tube is pre-suspended vertically on the chuck 12, its standard axial direction should be consistent with the axial direction of the rotation center axis of the chuck 12. Therefore, in this solution, the rotating shaft 21 is specifically set to a vertical state, so that the rotation center axes of the rotating shaft 21 and the chuck 12 are consistent. The laser beam path, as the reference line for determining the coaxiality of the quartz tube, should also be consistent with the standard axial direction of the quartz tube. That is, the laser beam path is parallel to the axial direction of the rotation center axes of the rotating shaft 21 and the chuck 12, i.e., the laser beam path is vertical. By measuring the parallelism of the axial direction of the quartz tube relative to the laser beam path, the degree of coaxiality of the quartz tube can be indicated. The higher the parallelism, the higher the coaxiality.

[0043] The quartz tube coaxiality measuring device also includes a tube wall adapter assembly, see [link / reference]. Figures 4-5As shown, the pipe wall adapter assembly includes a linear module 31 fixedly mounted on the side of the frame 11, a support block fixedly mounted on the slider of the linear module 31, a hollow tube 32 rotatably connected to the support block and fixedly sleeved outside the rotating shaft 21, a follower arm 33 fixedly connected to the hollow tube 32, a short arm 34 fixedly connected to one side of the hollow tube 32, and a spring 35 fixedly connected to the side of the short arm 34 facing the slider. The other end of the spring 35 is fixedly connected to the slider of the linear module 31. Furthermore, the pipe wall adapter assembly also includes a support arm 37 fixedly connected to the slider of the linear module 31 and located below the spring 35. One end of the support arm 37 is fixedly mounted with an electromagnetic push rod 36 for pushing the short arm 34.

[0044] It should be noted that in existing technologies, due to the transparency of the quartz tube, its characteristics of laser reflection, refraction, and transmission can affect the laser measurement of coaxiality. Therefore, this solution uses the degree of undulation (displacement) of the follower arm 33, which is attached to the quartz tube wall, as it slides on the tube wall surface to express the curvature of the tube wall. Furthermore, the degree of displacement of the follower arm 33 is measured by laser to verify the curvature of the quartz tube, thus proving whether the coaxiality of the quartz tube is qualified. If the coaxiality of the quartz tube is good, that is, if the quartz tube is not bent, the follower arm 33 should slide smoothly and steadily on the tube wall without any lateral undulation. This conversion design achieves the goal of avoiding direct laser irradiation of the quartz tube, completely avoiding the influence of laser transmission, reflection, and refraction on the detection.

[0045] The quartz tube coaxiality measuring device also includes a calibration measuring component, see [link / reference]. Figures 4-7 As shown, the calibration measurement assembly includes a second motor 41 fixedly mounted on one end of the follower arm 33, a turntable 42 fixedly mounted on the drive shaft of the second motor 41, and a plurality of light-transmitting holes 43 uniformly opened along the circumferential direction on the turntable 42. The diameter of each light-transmitting hole 43 gradually increases, and the diameter of the smallest light-transmitting hole 43 is consistent with the diameter of the laser beam. The center of all the light-transmitting holes 43 is located on a concentric circle on the turntable 42, and this concentric circle is concentric with the center of the turntable 42. The distance between the centers of each light-transmitting hole 43 is equal. In this embodiment, a total of 8 light-transmitting holes 43 are provided on the turntable 42, and the distance between adjacent light-transmitting holes 43 is 45°.

[0046] It should be noted that the lateral undulation of the follower arm 33 is detected by the laser in this embodiment by detecting whether the follower arm 33 blocks the path of the laser beam. If the path of the laser beam is not blocked by the follower arm 33, it means that the follower arm 33 has not generated lateral undulation; otherwise, it means that the follower arm 33 has generated lateral undulation. That is, a light-transmitting hole 43 is provided at one end of the follower arm 33, and the laser beam can pass through the light-transmitting hole 43 and be received normally. Once the follower arm 33 generates lateral undulation displacement due to the bending of the quartz tube (i.e., the follower arm 33 deflects), causing the light-transmitting hole 43 to shift, the laser beam will not be able to pass through the light-transmitting hole 43 and will be blocked by other parts of the follower arm 33. The receiver 24 will fail to receive the laser beam and issue an alarm, indicating that the coaxiality of the contact part between the quartz tube and the follower arm 33 does not meet the requirements.

[0047] The implementation process of this embodiment will be described in detail below:

[0048] First, the internal push rod of the electromagnetic push rod 36 extends, and one end of the push rod acts on the short arm 34, continuously pushing the short arm 34 towards the slider and compressing the spring 35. Then, the short arm 34 and the hollow tube 32 rotate, driving the follower arm 33 to rotate. Then, the linear module 31 moves, and its slider drives the entire tube wall adapter assembly to rise until it reaches the top of the linear module 31. Then, the quartz tube is fixed in the jaws of the chuck 12. The electromagnetic push rod 36 resets, and its internal push rod retracts. Then, under the elastic release of the spring 35, the short arm 34 drives the follower arm 33 to rotate in the opposite direction through the hollow tube 32 until the inner side of the follower arm 33 is attached to the tube wall of the quartz tube.

[0049] Then, the servo motor 25 is activated, and the transmitter 23 is turned on. The drive shaft of the servo motor 25 drives the rotating shaft 21 to rotate, which in turn drives the transmitter 23 and receiver 24 to rotate synchronously through the upper and lower swing arms 22. The rotation direction is towards the quartz tube. When the laser beam path intersects the concentric circle where the center of the light-transmitting aperture 43 is located, the rotation stops, and at the same time, the light-transmitting aperture 43 with the smallest diameter is completely aligned with the laser beam path. After alignment, the laser beam remains stationary, that is, the servo motor 25 stops rotating. The receiver 24's receiving power is used to determine whether the laser beam has completely passed through the light-transmitting aperture 43. When the laser beam has completely passed through the light-transmitting aperture 43, the receiver 24's receiving power is at its maximum. When the laser beam is blocked, the receiver 24's receiving power will decrease. The receiver 24's receiving power will be displayed on the device's touch screen. By observing the data on the screen, it can be determined whether the laser beam has completely passed through the light-transmitting aperture 43. This completes the laser beam deployment and calibration work.

[0050] Note: For ease of understanding, this implementation process discloses one method for laser beam deployment and calibration:

[0051] 1. Initially, adjust the rotating shaft 21 to rotate rapidly so that the laser beam falls on the turntable 42 as soon as possible, thus shortening the adjustment time;

[0052] 2. When the laser beam approaches the turntable 42, adjust the rotating shaft 21 to rotate slowly so that the laser beam roughly falls on the concentric circle where the center of the light-transmitting hole 43 is located, thus achieving coarse adjustment. Figures 4-7 As shown, the concentric circles should be clearly marked on the turntable 42 in the form of circles for easy observation;

[0053] 3. Rotate the turntable 42 so that the smallest diameter light-transmitting aperture 43 is aligned with the laser beam:

[0054] The rotation angles of turntable 42 and shaft 21 are continuously adjusted until the laser beam is fully aligned and passes through the minimum diameter light-transmitting hole 43, thus achieving fine-tuning. The laser power received by receiver 24 is used as the judgment mark. When the received power is at its maximum, it can be determined that the laser beam is fully aligned and passes through the minimum diameter light-transmitting hole 43.

[0055] After fine-tuning, the laser beam remains stationary in subsequent measurements, serving as a baseline for coaxiality determination and achieving the effect of locating the laser beam's position. It should be noted that the reason for aligning the laser beam with the smallest diameter aperture 43 is as follows: different diameter apertures 43 correspond to different allowable coaxiality thresholds. The position of the selected aperture 43 needs to be adjusted according to the coaxiality threshold requirements. Since the smallest diameter of the aperture 43 is consistent with the laser beam diameter, the laser beam can only pass through unobstructed when the center of the aperture is completely aligned with the laser axis. Only then can it be proven that the laser beam's axis passes precisely through the concentric circles on the turntable 42. If the laser beam is aligned with an aperture 43 of a different diameter (larger than the laser beam diameter), it cannot be concluded that the laser beam's axis passes through the concentric circles on the turntable 42 even when the laser beam passes through unobstructed. By using the smallest aperture 43 as a zero-point reference, after rotating the turntable 42 by a certain angle, the center of the other apertures 43 will always be aligned with the laser beam's axis. For example, rotating the turntable 42 by 45° will align the second small-diameter light-transmitting hole 43 with the axis of the laser beam; rotating the turntable 42 by 90° will align the third small-diameter light-transmitting hole 43 with the axis of the laser beam. The device's touchscreen has an adjustment bar for adjusting the rotation angle of the second motor 41. For example, inputting 45° into this adjustment bar will cause the second motor 41 to rotate the turntable 42 clockwise by 45°.

[0056] During the final measurement, a certain diameter light-transmitting hole 43 is selected as the standard for coaxiality measurement. Motor 13 drives the quartz tube on chuck 12 to rotate slowly, and then the slider drives the follower arm 33 on hollow tube 32 to move up and down slowly. When the coaxiality of the quartz tube is poor, the bent tube wall will force the follower arm 33 to move laterally. The displacement will cause the turntable 42 to shift, causing the laser beam to leave the light-transmitting hole 43 and be blocked by other parts of the turntable 42. The receiver 24 will issue an alarm when the receiving power decreases, indicating that the coaxiality of the contact part between the quartz tube and the follower arm 33 does not meet the requirements.

[0057] In this scheme, the diameter of the light-transmitting aperture 43 is used as the threshold for measuring the coaxiality of the quartz tube, as follows:

[0058] The core of aperture diameter design lies in establishing a mathematical correspondence between geometric parameters and tolerance thresholds. When the laser beam diameter is fixed, the diameter of the light-transmitting aperture 43 on the turntable 42 directly determines the maximum allowable radial displacement of the laser beam, i.e., the coaxiality threshold. Let the laser beam diameter be d (usually taken as 0.3mm-1mm) and the diameter of the light-transmitting aperture 43 be D, then the maximum allowable radial displacement ΔR can be expressed as:

[0059] ΔR=(Dd) / 2;

[0060] This formula reveals the linear mapping relationship between the diameter of the aperture 43 and the coaxiality threshold: D is greater than d, ΔR is a positive value, and it increases linearly with the increase of D. For example, if a laser beam with a diameter of 0.5 mm is used, when the diameter of the aperture 43 is 1.0 mm, the maximum allowable radial displacement is 0.25 mm; when the diameter of the aperture 43 increases to 1.5 mm, the allowable displacement increases to 0.5 mm, and the coaxiality threshold is relaxed by a factor of two.

[0061] During dynamic detection, this design achieves threshold control through several key steps: First, a fixed-diameter laser beam and a variable-diameter light-transmitting aperture 43 form a "dynamic shutter." When the displacement of the laser beam exceeds ΔR, the edge of the light-transmitting aperture 43 blocks the laser beam. Finally, the receiver 24 converts the optical signal into an electrical signal, reduces the receiving power of the receiver 24, and issues an alarm, thus achieving real-time determination of defective products.

[0062] The engineering design of the aperture diameter must follow the principle of matching laser optical characteristics with mechanical precision. The selection of laser beam diameter is fundamental. It is recommended to use the 1 / e² diameter definition of a Gaussian beam (energy percentage 86.5%), usually 0.3mm-1mm is appropriate: small diameter lasers (0.3mm-0.5mm) are suitable for high-precision detection (coaxiality threshold ≤0.1mm), and large diameter lasers (0.8mm-1mm) are suitable for loose threshold detection (threshold ≥0.2mm). The aperture diameter should be 0.2mm-2mm larger than the laser beam diameter. The specific difference is determined according to the target threshold, but the minimum difference should not be less than 0.2mm, otherwise it will be easy to make misjudgments due to assembly errors.

[0063] The machining accuracy of the hole directly affects the accuracy of the threshold. Key parameters include: diameter tolerance controlled within ±0.005mm, roundness error ≤0.003mm, and surface roughness Ra≤0.8μm. When there are burrs larger than 0.01mm on the edge of the hole, it will cause laser scattering, causing the receiver 24 to misjudge the state as blocked. Therefore, the edge of the hole needs to be rounded (corner radius 0.05mm-0.1mm) and precision boring with diamond tools to ensure the edge is smooth.

[0064] This solution allows for multiple threshold detections on the same device by changing the position of the light-transmitting aperture 43 with different aperture sizes, and the threshold switching time is short.

[0065] Furthermore, regarding the transmitter 23 in this solution, it should be noted that in this embodiment, the transmitter 23 is the core component that provides a "precise aiming signal" for the coaxiality detection of the quartz tube. It needs to be fully compatible with the detection scheme of physical follow-up and multi-aperture threshold. A red light transmitter 23 with a wavelength of 650nm is preferred. The visible light beam can quickly align with the smallest light-transmitting hole 43 of the multi-aperture turntable 42, which is convenient for reference calibration. With a collimating lens, the beam divergence angle is controlled within 0.1mrad to ensure that the beam passes through the light-transmitting hole 43 in a concentrated manner, avoiding misjudgment due to divergence. The power is selected as a low-power continuous light of 5mW-10mW, which not only meets the recognition requirements of the receiver 24, but also will not damage the quartz tube due to high temperature.

[0066] Regarding the receiver 24 in this solution, it should be noted that in this embodiment, the receiver 24 is the key to determining whether the laser passes through the light-transmitting aperture 43 normally. It needs to balance sensitivity, anti-interference and response speed: a photodiode (PD) receiver 24 is selected, whose high sensitivity can capture changes in light intensity caused by micron-level light blocking (even if the light intensity is only reduced by 10%), and accurately match the judgment logic of "aperture diameter threshold"; a 650nm narrowband filter is added to allow only the red light from the transmitter 23 to enter, and isolate stray light interference such as workshop lights; the response time is controlled within 1 microsecond to avoid missed judgment due to reaction delay, and to ensure that as soon as the coaxiality deviation of the quartz tube occurs, an alarm can be quickly triggered by the interruption of the optical signal.

[0067] The quartz tube coaxiality measuring device also includes a compensation component, see [link / reference]. Figures 6-8 As shown, it includes a short shaft 51 rotatably connected to the slider of the linear module 31, a support arm 52 fixedly connected to the short shaft 51, a second short arm 53 fixedly connected to one side of the short shaft 51, and a second spring 54 fixedly connected to the side of the second short arm 53 facing the slider. The other end of the second spring 54 is fixedly connected to the slider of the linear module 31. The support arm 52 and the follower arm 33 have the same structure and are symmetrically arranged about the axis of the chuck 12. Furthermore, the counteracting assembly also includes a second support arm 56 fixedly connected to the side of the slider of the linear module 31 and located below the second spring 54. One end of the second support arm 56 is fixedly mounted with an electromagnetic push rod 55 for pushing the second short arm 53.

[0068] When the follower arm 33 presses against the tube wall, it inevitably applies a lateral force to the quartz tube, which may affect the coaxiality of the quartz tube itself. In other words, the follower arm 33 risks bending the quartz tube. Therefore, the above design is used to counteract this force and improve measurement accuracy. Specifically, the electromagnetic push rod 2 55 resets its internal push rod (for convenience when clamping the quartz tube, the electromagnetic push rod 2 55 extends to push the support arm 52 away from the quartz tube). Under the elastic release of the spring 2 54, the short arm 2 53 drives the support arm 52 to reverse through the short shaft 51 until the inner side of the support arm 52 is in contact with the tube wall of the quartz tube, achieving the purpose of symmetrically applying force to counteract the lateral force of the follower arm 33. The support arm 52 and the follower arm 33 are symmetrically arranged, and the elastic preload cancels each other out, making the net lateral force close to zero. This avoids deformation of the quartz tube due to contact force and ensures that the detection deviation is the coaxiality error of the tube itself. The symmetrical arm eliminates deformation caused by lateral contact force, and the vertical suspension of the quartz tube eliminates radial deformation caused by gravity. The two work together to greatly reduce the detection error.

[0069] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0070] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A device for measuring the coaxiality of a quartz tube, characterized in that, include: The fixing assembly includes a frame (11) and a chuck (12) rotatably connected to the top of the frame (11). The laser deployment assembly includes a rotating shaft (21) rotatably connected to the side of the frame (11), two swing arms (22) fixedly connected to the upper and lower ends of the rotating shaft (21), and a transmitter (23) and a receiver (24) respectively fixedly installed at one end of the two swing arms (22). The tube wall adapter assembly includes a linear module (31) fixedly mounted on the side of the frame (11), a support block fixedly mounted on the slider of the linear module (31), a hollow tube (32) rotatably connected to the support block and fixedly sleeved outside the rotating shaft (21), a follower arm (33) fixedly connected to the hollow tube (32), a short arm (34) fixedly connected to one side of the hollow tube (32), and a spring (35) fixedly connected to the side of the short arm (34) facing the slider. The other end of the spring (35) is fixedly connected to the slider of the linear module (31). The calibration measurement assembly includes a second motor (41) fixedly mounted on one end of the follower arm (33), a turntable (42) fixedly mounted on the drive shaft of the second motor (41), and a plurality of light-transmitting holes (43) uniformly opened on the turntable (42) along the circumferential direction. The diameter of each light-transmitting hole (43) gradually increases and the diameter of the smallest light-transmitting hole (43) is consistent with the diameter of the laser beam. The center of each light-transmitting hole (43) is located on a concentric circle on the turntable (42).

2. The quartz tube coaxiality measuring device according to claim 1, characterized in that: The axis of the chuck (12) is vertical, the rotating shaft (21) is vertical, and the laser beam emitted by the transmitter (23) is vertical.

3. The quartz tube coaxiality measuring device according to claim 1, characterized in that: The fixing assembly also includes a motor (13) fixedly mounted on the top of the frame (11), and the drive shaft of the motor (13) is fixedly connected to the chuck (12).

4. The quartz tube coaxiality measuring device according to claim 1, characterized in that: The laser deployment assembly also includes a servo motor (25) fixedly mounted on the frame (11), with the drive shaft of the servo motor (25) fixedly connected to the bottom end of the rotating shaft (21).

5. The quartz tube coaxiality measuring device according to claim 1, characterized in that: The pipe wall adapter assembly also includes a support arm (37) fixedly connected to the side of the slider of the linear module (31), and an electromagnetic push rod (36) for pushing the short arm (34) is fixedly installed at one end of the support arm (37).

6. The quartz tube coaxiality measuring device according to claim 1, characterized in that: It also includes a counteracting assembly, which includes a short shaft (51) rotatably connected to the slider of the linear module (31), a support arm (52) fixedly connected to the short shaft (51), a second short arm (53) fixedly connected to one side of the short shaft (51), and a second spring (54) fixedly connected to the side of the second short arm (53) facing the slider. The other end of the second spring (54) is fixedly connected to the slider of the linear module (31). The support arm (52) and the follower arm (33) have the same structure and are symmetrically arranged about the axis of the chuck (12).

7. The quartz tube coaxiality measuring device according to claim 6, characterized in that: The offset assembly also includes a second support arm (56) fixedly connected to the side of the slider of the linear module (31), and an electromagnetic push rod (55) for pushing the second short arm (53) is fixedly installed at one end of the second support arm (56).

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