Noise vibration test equipment and rotating shuttle calibration method

Abstract

According to the noise vibration test equipment and the rotating shuttle calibration method, a rotating shuttle to be tested is installed on a rotating shuttle shaft driven by a driving device to rotate, an outer shuttle frame is fixed through a rotating shuttle positioning device, and the assembly and operation states of the rotating shuttle in a sewing machine are truly simulated; the noise and vibration parameters during high-speed operation are collected in real time by means of the noise and vibration detector, the noise and vibration performance of the rotating shuttle can be quantitatively evaluated before the whole machine is assembled, and interference of other parts of the whole machine is avoided. According to the method, the unqualified rotating shuttle can be recognized and debugged in advance, the situation that the noise and vibration of the whole machine exceed the standard due to the individual gap difference of the rotating shuttle is effectively prevented, front screening and grading management of the rotating shuttle quality are achieved, and the one-time assembly yield of the whole machine is remarkably improved; meanwhile, complex debugging after the whole machine is assembled is omitted, the rework, replacement and labor cost is greatly reduced, and the production efficiency and the product consistency are improved.

Description

Technical Field

[0001] This application relates to the field of sewing machine manufacturing technology, and in particular to a noise and vibration testing device and a rotary hook calibration method. Background Technology

[0002] A sewing machine is a mechanical device that uses one or more sewing threads to create specific stitches on fabric, thereby weaving or sewing one or more layers of fabric together. During the sewing process, the rotary hook, as one of the key components of the sewing machine, plays a crucial role in receiving the bobbin thread and ensuring its smooth and reliable supply. The rotary hook typically consists of an inner shuttle and an outer shuttle, which are assembled together by a track structure, thus creating a certain gap. If this gap is not properly controlled, the inner and outer shuttles may collide due to misalignment during high-speed operation, resulting in significant vibration and noise. This not only affects the sewing quality but also reduces the overall stability of the machine and the user experience.

[0003] To alleviate this problem, existing technologies typically include a hollow oil passage inside the shuttle shaft installed on the outer shuttle frame. This passage delivers lubricating oil to the gap between the inner and outer shuttle frames to achieve lubrication and buffering, thereby suppressing vibration and noise to some extent.

[0004] Nevertheless, due to manufacturing processes and assembly errors, the actual gaps between the inner and outer shuttle frames of the same batch of rotary hooks are difficult to maintain consistently, resulting in significant differences in the vibration and noise levels of each hook after assembly. Currently, in the traditional sewing machine manufacturing process, there is a lack of effective means to test and evaluate the noise and vibration performance of rotary hooks. Testing is often only conducted after the entire machine is assembled. Once it is found that a sewing machine has excessive noise and vibration due to a problem with the rotary hook, the only solution is usually to replace the rotary hook, which is not only inefficient but also wastes a lot of manpower, material resources, and time. Summary of the Invention

[0005] The purpose of this application is to provide a noise and vibration testing device and a rotary hook calibration method, which improves the first-pass yield, production efficiency and product consistency of sewing machine assembly, and reduces costs.

[0006] The embodiments of this application can be implemented as follows: In a first aspect, the present invention provides a noise and vibration testing device, including a base plate, a driving device, a rotary shuttle shaft seat, a rotary shuttle shaft, a rotary shuttle positioning device, and a noise and vibration detector; Both the drive device and the rotary shaft seat are mounted on the base plate; The rotary shuttle shaft is rotatably mounted on the rotary shuttle shaft seat, and one end of the rotary shuttle shaft is connected to the drive device, while the other end of the rotary shuttle shaft is used for mounting the rotary shuttle to be tested. The drive device is used to drive the rotary hook shaft to rotate; The rotary shuttle positioning device is installed on the rotary shuttle shaft seat to keep the outer shuttle frame of the rotary shuttle under test fixed relative to the rotary shuttle shaft seat; The noise and vibration detector is used to detect the noise and vibration parameters of the rotary shuttle under test.

[0007] In an optional implementation, the noise vibration detector includes a microphone and a vibration sensor; The microphone is used to detect the noise parameters of the rotary shuttle under test; The vibration sensor is mounted on the shuttle shaft seat and is used to detect the vibration parameters of the shuttle under test.

[0008] In an optional implementation, the microphone includes a first microphone and a second microphone. The first microphone and the end of the rotary hook shaft used to mount the rotary hook to be tested are arranged facing each other. The second microphone is arranged at a preset angle to the rotary shaft and faces the end of the rotary shaft used to mount the rotary shuttle to be tested.

[0009] In an optional implementation, the distance between the first microphone and the rotary hook to be tested is 300 mm; The distance between the second microphone and the rotary hook to be tested is 450mm; The preset included angle is 45°.

[0010] In an optional embodiment, the rotary shaft seat includes a base and a front bearing seat and a rear bearing seat mounted on the base; The base is mounted on the substrate; The rotary shuttle shaft passes through the front bearing housing and the rear bearing housing, and the end of the rotary shuttle shaft extending from the front bearing housing away from the rear bearing housing is used to install the rotary shuttle to be tested; The vibration sensor is mounted on the front bearing housing.

[0011] In an optional embodiment, the rotary shuttle positioning device includes a mounting base and a positioning hook mounted on the mounting base. The mounting base is mounted on the rotary shuttle shaft seat, and the positioning hook is used to abut against the outer shuttle frame of the rotary shuttle to be tested.

[0012] In an optional embodiment, the noise and vibration testing equipment further includes a lubrication device, which includes an oil tank and a regulating valve connected to the oil tank; The oil tank is mounted on the base plate, and the regulating valve is connected to the rotary shuttle shaft seat to regulate the amount of oil supplied to the rotary shuttle under test.

[0013] In an optional embodiment, the noise and vibration testing equipment further includes a speed sensor mounted on the base plate for real-time detection of the rotational speed of the rotary hook shaft.

[0014] Secondly, the present invention provides a rotary shuttle calibration method, implemented based on the noise and vibration testing equipment described in any of the foregoing embodiments, the method comprising: Obtain noise and vibration parameters from the noise and vibration detector; Determine whether the noise and vibration parameters meet the preset conditions; If so, confirm that the rotary hook to be tested is qualified; If not, adjust the gap of the rotary hook under test until the noise and vibration parameters meet the preset conditions.

[0015] In an optional implementation, the noise vibration parameters include noise sound pressure level, noise sharpness, noise loudness, noise jitter, noise roughness, and root mean square value of vibration. The preset conditions are that any one of the following: noise sound pressure level, noise sharpness, noise loudness, noise vibration, noise roughness, and root mean square value of vibration is within its respective standard reference range.

[0016] The beneficial effects of the embodiments of this application include, for example: By mounting the rotary hook under test on a rotary hook shaft that can be rotated by a drive device, and using a rotary hook positioning device to keep the outer hook frame fixed relative to the rotary hook shaft seat, the assembly and operation conditions of the rotary hook in actual sewing machine operation are simulated. Based on this, noise and vibration parameters of the rotary hook during high-speed operation are collected in real time using a noise and vibration detector. This allows for a quantitative assessment of the noise and vibration performance of the rotary hook itself before the entire machine is assembled, effectively avoiding errors caused by the operation of other sewing machine components in the measurement of rotary hook noise and vibration. Rotary hooks with substandard noise and vibration performance can be adjusted in advance until they meet the requirements. Therefore, on the one hand, it effectively avoids the problem of excessive noise and vibration in the whole machine caused by differences in individual rotary hook gaps; on the other hand, it achieves pre-screening and graded management of rotary hook quality, significantly improving the first-pass yield of the entire sewing machine assembly. Furthermore, this testing method does not rely on the complex debugging process after the entire machine is assembled, greatly reducing rework, replacement, and labor costs caused by defective rotary hooks, improving production efficiency and product consistency, and providing data support for the optimization of rotary hook manufacturing processes. It has good technical practicality and economic benefits. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is one of the schematic diagrams of a noise and vibration testing device; Figure 2 This is the second schematic diagram of a noise and vibration testing device; Figure 3 A schematic diagram of a noise and vibration testing device with the microphone concealed. Figure 4 This is the third schematic diagram of a noise and vibration testing device; Figure 5 for Figure 2 Enlarged view of region I in the image; Figure 6 This is a flowchart of the rotary shuttle calibration method.

[0019] Icons: 110-Baseboard; 120-Drive unit; 121-Fixed seat; 122-Drive motor; 123-Drive wheel; 124-Driven wheel; 125-Synchronous belt; 130-Hook shaft seat; 131-Base; 132-Front bearing seat; 133-Rear bearing seat; 140-Hook shaft; 150-Hook positioning device; 151-Mounting seat; 152-Positioning hook; 160-Noise and vibration detector; 161-First microphone; 162-Second microphone; 163-Vibration sensor; 170-Speed ​​sensor; 180-Lubrication device; 181-Oil tank; 182-Regulating valve; 200-Hook. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0022] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0023] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0025] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" 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 mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0026] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0027] refer to Figures 1 to 3 This application discloses a noise and vibration testing device, which includes a base plate 110, a drive device 120, a shuttle shaft seat 130, a shuttle shaft 140, a shuttle positioning device 150, and a noise and vibration detector 160. Both the drive unit 120 and the rotary hook bearing 130 are mounted on the base plate 110; The rotary shuttle shaft 140 is rotatably mounted on the rotary shuttle shaft seat 130, and one end of the rotary shuttle shaft 140 is connected to the drive device 120, while the other end of the rotary shuttle shaft 140 is used for mounting the rotary shuttle 200 to be tested. Drive unit 120 is used to drive the rotary hook shaft 140 to rotate; The rotary shuttle positioning device 150 is installed on the rotary shuttle shaft seat 130 to keep the outer shuttle frame of the rotary shuttle 200 under test fixed relative to the rotary shuttle shaft seat 130. The noise and vibration detector 160 is used to detect the noise and vibration parameters of the rotary hook 200 under test.

[0028] Thus, by mounting the rotary hook 200 to be tested on the rotary hook shaft 140, which can be rotated by the drive device 120, and using the rotary hook positioning device 150 to keep the outer shuttle frame fixed relative to the rotary hook shaft seat 130, the assembly and operation conditions of the rotary hook 200 in the actual operation of the sewing machine are simulated. Based on this, the noise and vibration parameters of the rotary hook 200 during high-speed operation are collected in real time by the noise and vibration detector 160. Before the entire machine is assembled, the noise and vibration performance of the rotary hook 200 itself can be quantitatively evaluated based on these noise and vibration parameters. This effectively avoids errors caused by the operation of other parts of the sewing machine affecting the noise and vibration measurement of the rotary hook 200, and allows for the early adjustment of rotary hooks 200 with unqualified noise and vibration performance until they meet the standards. Therefore, on the one hand, the problem of excessive noise and vibration of the entire machine caused by individual gap differences in the rotary hook 200 is effectively avoided; on the other hand, the quality of the rotary hook 200 is pre-screened and graded, significantly improving the first-pass yield of the entire sewing machine assembly. In addition, this testing method does not rely on the complex debugging process after the complete machine is assembled, which greatly reduces the rework, replacement and labor costs caused by defects in the rotary hook 200, improves production efficiency and product consistency, and provides data support for the optimization of the rotary hook 200 manufacturing process. It has good technical practicality and economic benefits.

[0029] It is understandable that the drive device 120 only needs to be able to drive the rotary hook shaft 140 to rotate, and its specific form is not limited. Therefore, different types of drive schemes can be flexibly selected according to the test requirements, which improves the versatility and adaptability of the equipment.

[0030] For example, the drive unit 120 includes a fixed base 121, a drive motor 122 and a transmission assembly. The fixed base 121 is mounted on the base plate 110, the drive motor 122 is mounted on the fixed base 121, and the transmission assembly connects the output shaft of the drive motor 122 and the rotary shaft 140.

[0031] In this way, when a drive unit 120, including a fixed base 121, a drive motor 122, and a transmission assembly, is used, the fixed base 121 can be securely mounted on the base plate 110, providing reliable support for the drive motor 122. The drive motor 122, as a power source, can smoothly transmit rotational motion to the shuttle shaft 140 through the transmission assembly, thereby driving the shuttle 200 under test to operate at a set speed. This structure is not only easy to install and stable in operation, but also facilitates speed adjustment to simulate the working state of the shuttle 200 under different working conditions of a sewing machine, ensuring that the vibration and noise detection results are more representative and repeatable.

[0032] The transmission assembly can specifically adopt a belt drive method, for example, it includes a synchronous belt 125, a driving pulley 123 and a driven pulley 124; the driving pulley 123 is coaxially mounted on the output shaft of the drive motor 122, the driven pulley 124 is coaxially mounted on the shuttle shaft 140, and the synchronous belt 125 is wound around the driving pulley 123 and the driven pulley 124, thereby smoothly and quietly transmitting the rotational power of the drive motor 122 to the shuttle shaft 140.

[0033] Of course, the transmission components can also be gear reducers, chains and sprockets, etc. There are no restrictions on the specific transmission method, as long as it can achieve effective transmission.

[0034] Since the vibration and noise characteristics of the rotary hook 200 are highly dependent on its operating speed, the dynamic response caused by gaps, imbalances or lubrication conditions may vary significantly at different speeds.

[0035] Therefore, in this embodiment, the noise and vibration testing equipment also includes a speed sensor 170 (e.g., a Hall sensor, a photoelectric sensor, etc.), which is mounted on the substrate 110 and is used to detect the rotational speed of the rotary shaft 140 in real time.

[0036] In this way, the actual rotational speed of the rotary shaft 140 is detected in real time and accurately by the speed sensor 170 mounted on the base plate 110, thereby ensuring that the entire test process is carried out under controllable and reproducible rotational speed conditions. Therefore, real-time acquisition of rotational speed data not only provides a key operating condition benchmark for vibration and noise parameters, but also enables the test results to have a clear speed correspondence, which is convenient for establishing a multi-dimensional performance curve of "rotational speed-vibration-noise".

[0037] Furthermore, when there are load fluctuations or transmission slippage in the drive unit 120 (such as slight slippage of the timing belt 125), relying solely on the motor's set speed may not accurately reflect the actual operating state of the rotary hook shaft 140. However, by directly monitoring the rotational speed of the rotary hook shaft 140, such errors can be effectively eliminated, improving the accuracy and reliability of the test data.

[0038] It should also be noted that in the automated testing process, the feedback signal provided by the speed sensor 170 can be used to achieve closed-loop speed control, ensuring that each rotary hook 200 under test is evaluated at the standard specified speed point (such as the sewing machine's rated speed of 5000 rpm), thereby ensuring the consistency and fairness of test results between batches.

[0039] The noise and vibration detector 160 includes a microphone and a vibration sensor 163; the microphone is used to detect the noise parameters of the rotary shuttle 200 under test; the vibration sensor 163 is mounted on the rotary shuttle shaft seat 130 and is used to detect the vibration parameters of the rotary shuttle 200 under test.

[0040] In this way, the microphone is used to collect the noise parameters generated by the rotary shuttle 200 during high-speed operation, which can accurately reflect its acoustic performance; the vibration sensor 163 is directly mounted on the rotary shuttle shaft seat 130, close to the installation position of the rotary shuttle 200, and can highly sensitively pick up mechanical vibration signals caused by uneven gaps between the inner and outer shuttle frames of the rotary shuttle 200 or assembly eccentricity. By simultaneously acquiring the two key indicators of noise and vibration, it is beneficial to conduct a multi-dimensional and quantitative comprehensive evaluation of the noise and vibration parameters of the rotary shuttle 200, significantly improving the accuracy and reliability of the judgment.

[0041] refer to Figure 4 The microphone includes a first microphone 161 and a second microphone 162; the first microphone 161 and the end of the rotary hook shaft 140 used to mount the rotary hook 200 to be tested are arranged opposite each other. The second microphone 162 is arranged at a preset angle to the rotary shaft 140, and faces the end of the rotary shaft 140 used to install the rotary shuttle 200 to be tested.

[0042] In this way, the first microphone 161 and the second microphone 162 are aligned with the mounting end of the shuttle 200 under test at different spatial orientations. The first microphone 161 is directly facing the end face of the shuttle 200 under test, which can directly and efficiently capture the near-field noise generated in front of the shuttle 200 during axial operation. The second microphone 162 is arranged at a preset angle (e.g., 30~60°) with the shuttle shaft 140 to pick up the noise components radiated by the shuttle 200 in the radial or lateral direction, simulating the position of the sewing machine operator's ear, thereby more comprehensively reflecting the sound field characteristics in three-dimensional space and improving the coverage and representativeness of noise detection.

[0043] Meanwhile, by comparing the noise signals collected by the two microphones, it is also possible to help identify the directional characteristics of the noise source or determine whether the rotary hook 200 has specific defects such as eccentricity or imbalance, providing richer data dimensions for fault diagnosis and quality grading.

[0044] The distance between the first microphone 161 and the rotary shuttle 200 under test is 300mm. This distance conforms to the near-field noise measurement specifications and can effectively capture the high-frequency components and local sound source characteristics generated when the rotary shuttle 200 is running, ensuring high-sensitivity detection of the noise level of the rotary shuttle 200 itself.

[0045] The distance between the second microphone 162 and the rotary hook 200 under test is 450mm, with a preset included angle of 45°, which effectively simulates the typical position and distance of a sewing machine operator's ear during normal operation. This arrangement not only reproduces the sound propagation path and attenuation characteristics in actual use scenarios, but also makes the measured noise parameters closer to the operator's real listening experience, significantly improving the human factors engineering rationality and user experience relevance of noise assessment.

[0046] By combining near-field high-precision measurement (first microphone 161) with human ear perception simulation measurement (second microphone 162), this dual-microphone system realizes a dual evaluation dimension of equipment performance and human ear perception. It can be used to objectively determine the manufacturing quality of the rotary shuttle 200 and provide a basis for optimizing the noise comfort of the whole machine.

[0047] Continue to refer to Figures 1 to 3 In this embodiment, the rotary shuttle shaft seat 130 includes a base 131 and a front bearing seat 132 and a rear bearing seat 133 mounted on the base 131; the base 131 is mounted on the base plate 110; the rotary shuttle shaft 140 passes through the front bearing seat 132 and the rear bearing seat 133, and one end of the rotary shuttle shaft 140 extending from the front bearing seat away from the rear bearing seat 133 is used to mount the rotary shuttle 200 to be tested; the vibration sensor 163 is mounted on the front bearing seat 132.

[0048] In this way, since the rotary shuttle shaft seat 130 includes a base 131 mounted on the base plate 110, and a front bearing seat 132 and a rear bearing seat 133 mounted on the base 131, the rotary shuttle shaft 140 is supported at both ends and stably inserted through the front and rear bearing seats 133, forming a highly coaxial rotary support structure, which effectively ensures the rotational accuracy and dynamic stability of the rotary shuttle 200 during high-speed operation. The rotary shuttle shaft 140 extends from the side of the front bearing seat 132 away from the rear bearing seat 133, and is used to mount the rotary shuttle 200 under test, facilitating quick assembly, disassembly, and positioning of the rotary shuttle 200, while avoiding interference from the rear bearing seat 133 to the noise and vibration measurement of the rotary shuttle 200.

[0049] The vibration sensor 163 is directly mounted on the front bearing housing 132, at the support point near the mounting position of the rotary shuttle 200 under test. This allows for the most direct and sensitive detection of minute vibration signals caused by uneven gaps, eccentricity, or assembly errors in the inner and outer shuttle frames of the rotary shuttle 200, minimizing signal attenuation or distortion caused by structural transmission paths. Compared to placing the sensor on the base plate 110 or other indirect locations away from the rotary shuttle 200, this arrangement significantly improves the signal-to-noise ratio and response accuracy of vibration detection, enabling the collected vibration parameters to more accurately reflect the dynamic performance of the rotary shuttle 200 under test.

[0050] Of course, in some embodiments, the noise and vibration detector 160 may also employ other types of sensors, such as a laser Doppler vibrometer, an accelerometer array, a sound intensity probe, a microphone array, or a fiber optic vibration sensor 163.

[0051] refer to Figure 5 The rotary shuttle positioning device 150 includes a mounting base 151 and a positioning hook 152 mounted on the mounting base 151. The mounting base 151 is mounted on the rotary shuttle shaft seat 130 (specifically the front bearing seat 132), and the positioning hook 152 is used to hold the outer shuttle frame of the rotary shuttle 200 to be tested.

[0052] In this way, since the rotary hook positioning device 150 includes a mounting base 151 and a positioning hook 152 disposed thereon, and the mounting base 151 is firmly fixed on the rotary hook shaft seat 130, the entire positioning structure has good rigidity and positional stability. During the test, the positioning hook 152 can accurately abut against the outer shuttle frame of the rotary hook 200 under test, thereby effectively limiting its axial movement or circumferential displacement during high-speed rotation, ensuring that the rotary hook 200 operates under simulated actual assembly conditions, that is, the outer shuttle frame remains relatively stationary, while the inner shuttle frame rotates with the rotary hook shaft 140, which is consistent with the actual movement relationship of the rotary hook 200 when the sewing machine is working.

[0053] This positioning method, which keeps the outer frame of the rotary hook 200 relatively fixed, is not only simple in structure and convenient in operation, making it easy to quickly clamp and disassemble rotary hooks 200 of different specifications, but also significantly reduces the additional vibration interference caused by the free swaying of the rotary hook 200 or loose assembly through physical limiting. This allows the data collected by the noise and vibration detector 160 to more accurately reflect the performance differences of the rotary hook 200 caused by inherent factors such as manufacturing gaps and concentricity deviations.

[0054] Continue to refer to Figures 1 to 3 The noise and vibration testing equipment also includes a lubrication device 180, which includes an oil tank 181 and a regulating valve 182 connected to the oil tank 181. The oil tank 181 is mounted on the base plate 110, and the regulating valve 182 (e.g., a flow regulating valve 182) is connected to the rotary hook shaft seat 130 to regulate the amount of oil supplied to the rotary hook 200 under test, thereby accurately simulating the lubrication conditions of the rotary hook 200 under actual sewing machine operating conditions during the test. This design allows the test to not only reflect the performance of the rotary hook 200 in a dry or unlubricated state, but also to realistically reproduce its dynamic behavior under oil lubrication conditions.

[0055] The oil supply can be controlled and adjusted via regulating valve 182. Testers can set corresponding lubrication parameters according to different rotary hook 200 models, speed requirements, or process standards to achieve comparative testing under multiple operating conditions. For example, testing the noise and vibration response under low oil supply, standard oil supply, and excessive oil supply at the same speed helps to evaluate the sensitivity of the rotary hook 200 to lubrication conditions and identify problems such as insufficient lubrication noise or oil film oscillation caused by unreasonable clearance design.

[0056] Furthermore, the integration of the lubrication device 180 enables the entire equipment to have a more complete functional closed loop. It can not only detect the manufacturing quality of the rotary hook 200 body but also verify its matching performance with the lubrication system, providing direct data support for the structural optimization of the rotary hook 200 (such as oil passage design and clearance tolerance) and the formulation of overall lubrication strategies. At the same time, standardized oil supply control improves the consistency and repeatability of test results, avoiding misjudgments caused by uneven manual oiling, further enhancing the equipment's quality screening capabilities and engineering practicality on the production floor.

[0057] Of course, it is understandable that components such as the noise and vibration detector 160, drive device 120, speed sensor 170, and regulating valve 182 can all be connected to a control system (such as an intelligent control platform based on PLC, industrial computer, or embedded system) to realize full parameter perception, collaborative control, and data fusion in the testing process. Through the control system, multi-source signals such as the rotational speed of the rotary shaft 140, vibration acceleration, noise sound pressure level and spectrum characteristics, and oil supply flow can be acquired in real time, and automatic analysis and comprehensive judgment can be performed according to the preset evaluation criteria.

[0058] Based on this, the system can execute standardized testing procedures. For example, starting the drive unit 120 raises the rotary hook 200 to the target speed, and using the speed sensor 170 to stabilize the speed in a closed loop, simultaneously recording vibration and noise data under lubrication conditions. Combining the speed information, frequency domain / time domain features are extracted, the system automatically compares the results with the pass / fail threshold, outputs a "pass / fail" conclusion, and generates a test report. The entire process requires no manual intervention, significantly improving testing efficiency, consistency, and traceability.

[0059] Furthermore, the control system also supports data storage, statistical analysis, and quality trend early warning functions. For example, it can identify that the average noise level of a certain batch of rotary hook 200s is too high and promptly provide feedback to the manufacturing end to adjust the assembly process; or it can classify and manage products that are close to passing quality for use in the assembly of different grades of complete machines. This "detection-evaluation-feedback" closed-loop mechanism not only solves the problem of lag caused by the traditional reliance on final inspection of the entire machine, but also promotes the transformation of rotary hook 200 manufacturing towards intelligent and digital quality control.

[0060] This application also discloses a rotary hook 200 calibration method, which is implemented based on the noise and vibration testing equipment described in the above embodiments. This method can be stored as a program segment in the aforementioned control system and can be read, written, and executed by the control system. Figure 6 , Figure 6 This is a flowchart illustrating the method of an embodiment of this application. It should be noted that, in... Figure 6 The steps shown in the flowchart can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be performed in a different order than that shown here. The following is a further discussion of... Figure 6 The specific process shown will be explained in detail.

[0061] The calibration method for the rotary shuttle 200 includes: S100, acquire noise and vibration parameters from noise and vibration detector 160; S200, determine whether the noise and vibration parameters meet the preset conditions; S300, if so, confirm that the rotary hook 200 to be tested is qualified; S400, if not, adjust the gap of the rotary hook 200 under test until the noise and vibration parameters meet the preset conditions.

[0062] By using noise and vibration parameters as the core criteria, a closed-loop calibration process guided by actual dynamic performance is constructed. First, the system acquires objective data from the noise and vibration detector 160 in real time, avoiding the instability of traditional methods that rely on subjective listening or experience. Then, these parameters are automatically compared with pre-set technical standards (such as enterprise internal control limits, industry specifications, or overall machine assembly requirements) to achieve quantitative and standardized judgment of the quality of the rotary hook 200.

[0063] When the test results do not meet the preset conditions, the system does not directly discard the rotary hook 200. Instead, it enters the debugging phase, where the dynamic balance and operational stability are optimized by fine-tuning the assembly gap between the inner and outer shuttle frames of the rotary hook 200 under test (e.g., replacing shims, adjusting the clamping force, or repairing the mating surfaces). The system is then repeatedly tested until the noise and vibration parameters meet the standards. This iterative "detection-feedback-correction" mechanism significantly improves the repairability and utilization rate of high-value rotary hook 200s.

[0064] Furthermore, compared to the traditional passive approach of "discovering problems after assembly and then reworking," this calibration method moves quality control forward to the individual testing stage of the rotary hook 200. This not only significantly reduces the defect rate and rework costs after the entire machine is assembled, but also provides quantifiable basis for improving the manufacturing process.

[0065] In detail, noise and vibration parameters include noise sound pressure level, noise sharpness, noise loudness, noise vibration, noise roughness, and root mean square value of vibration. The preset conditions are that any one of the following: noise sound pressure level, noise sharpness, noise loudness, noise vibration, noise roughness, and root mean square value of vibration is within its respective standard reference range.

[0066] Thus, the noise vibration parameters used in this embodiment not only include traditional noise sound pressure level (used to measure overall noise intensity) and root mean square (RMS) vibration values ​​(reflecting the magnitude of vibration energy), but also introduce higher-order perceptual indices based on psychoacoustic models: noise sharpness, loudness, fluctuation strength, and roughness. These parameters comprehensively characterize the "auditory quality" of the rotary hook 200's operating noise from the perspectives of human ear perception of the sound spectrum centroid, subjective loudness, low-frequency modulation fluctuations, and mid-to-high-frequency periodic instability. For example, even if two rotary hook 200s have similar sound pressure levels, if their sharpness or roughness is higher, they may still be perceived as "harsh" or "chaotic" by the operator, affecting user comfort. Therefore, relying solely on a single physical quantity is insufficient to meet the requirements of high-end sewing equipment for quiet operation.

[0067] By setting standard reference ranges for each parameter (which can be derived from statistical analysis of a large amount of qualified whole machine test data) and using "any parameter exceeding the limit is deemed unqualified" as a preset condition, this method achieves multi-dimensional, high-precision, and human-centered quality control of the rotary hook 200's dynamic performance. This "one-vote veto" criterion ensures that any defects that may cause unpleasant user experience (such as high-frequency howling, periodic clicking sounds, oil film flutter, etc.) can be effectively intercepted.

[0068] During the calibration process, if a parameter exceeds the limit, technicians can combine the characteristics of each parameter to diagnose the root cause of the problem, for example: If the sharpness is high, it may indicate that the gap between the inner and outer shuttles is too small, resulting in high-frequency friction. Abnormal roughness or vibration may reflect periodic impacts caused by eccentricity of the rotary hook 200 or uneven lubrication. If the vibration RMS is significantly higher than normal, it may be due to misalignment during assembly or loose structure.

[0069] Based on this, targeted gap adjustments are made (such as fine-tuning the outer shuttle clamping force, replacing washers of different thicknesses, and repairing the inner shuttle track), and then retesting and verifying to form a closed-loop optimization process of "perception-diagnosis-correction-confirmation".

[0070] Of course, it is understandable that noise and vibration parameters are not limited to the aforementioned noise sound pressure level, noise sharpness, noise loudness, noise jitter, noise roughness, and root mean square vibration value; depending on the actual testing objectives, product positioning, or user needs, more evaluation parameters can be introduced, such as: Peak Value: Used to capture instantaneous impacts or abnormal vibrations that may occur during the operation of the rotary hook 200. It is highly sensitive to identifying defects such as loose assembly and local bumps. Vibration kurtosis: reflects the intensity of the pulse component in the vibration signal, which helps to detect unsteady faults such as bearing micro-damage or gap abrupt changes at an early stage; Spectral characteristic parameters (such as dominant frequency amplitude, harmonic components, and harmonic energy ratio): Through Fast Fourier Transform (FFT) analysis, resonance or interference sources related to the natural frequency or rotation frequency of the Spinner 200 structure can be identified. A-weighted / C-weighted sound pressure level (dBA / dBC): Simulates the frequency response characteristics of the human ear under different sound intensities, which is closer to the actual listening experience; Total Harmonic Distortion (THD): Used to quantify the nonlinear distortion component in noise signals, and to help determine whether there is mechanical interference or lubrication failure; Sound Power Level: Reflects the overall radiation capability of the rotary shuttle 200 as a noise source, and is suitable for performance comparison between different test environments; Order Analysis: The vibration or noise signal is decomposed according to the speed-related order to accurately locate the fault characteristics directly related to rotating parts (such as the impact generated by the inner shuttle frame every revolution). Comprehensive psychoacoustic indicators (such as annoyance level and pleasure level): Based on a multi-dimensional perception model, multiple psychoacoustic parameters are integrated to provide a comprehensive evaluation that is closer to the subjective experience of end users.

[0071] In summary, this embodiment has at least the following advantages compared to the prior art: 1. Compared with the traditional method of testing the noise and vibration of the rotary hook 200 on a sewing machine, this method can effectively reduce the error in measuring the noise of the rotary hook 200 caused by the operation of other parts of the sewing machine; 2. A microphone is placed 450mm above the rotary hook 200 to collect noise, which can effectively simulate the position of the operator's ear, making the measurement results closer to the actual hearing of the operator. 3. The noise and vibration level of the rotary shuttle 200 is described by measuring multiple parameters, which is more complete than the traditional method of measuring sound pressure level. This allows the noise and vibration of the rotary shuttle 200 to be parameterized, eliminating the need to rely on traditional human hearing to judge the noise of the rotary shuttle 200 and standardizing the measurement. 4. Using a rotary hook 200 noise and vibration testing device to test the noise and vibration of the rotary hook 200 before it is installed on the sewing machine and to adjust the gap of the rotary hook 200 can effectively avoid the noise and vibration problems of the whole machine caused by the large noise and vibration of the rotary hook 200. It can also significantly reduce rework and waste in the sewing machine assembly process and improve production efficiency.

[0072] Finally, 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.

[0073] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A noise and vibration testing apparatus, characterized by comprising: The device comprises a base plate (110), a driving device (120), a rotating hook shaft base (130), a rotating hook shaft (140), a rotating hook positioning device (150) and a noise and vibration detector (160); The driving device (120) and the rotating hook shaft base (130) are both mounted on the base plate (110); The rotating hook shaft (140) is rotatable and penetrates through the rotating hook shaft base (130), one end of the rotating hook shaft (140) is connected with the driving device (120), and the other end of the rotating hook shaft (140) is used for mounting the rotating hook (200) to be tested; The driving device (120) is used for driving the rotating hook shaft (140) to rotate; The rotating hook positioning device (150) is mounted on the rotating hook shaft base (130) and is used for keeping the outer hook frame of the rotating hook (200) to be tested fixed relative to the rotating hook shaft base (130); The noise and vibration detector (160) is used for detecting the noise and vibration parameters of the rotating hook (200) to be tested.

2. The noise and vibration testing apparatus of claim 1, wherein, The noise and vibration detector (160) comprises a microphone and a vibration sensor (163); The microphone is used for detecting the noise parameters of the rotating hook (200) to be tested; The vibration sensor (163) is arranged on the rotating hook shaft base (130) and is used for detecting the vibration parameters of the rotating hook (200) to be tested.

3. The noise and vibration test apparatus according to claim 2, wherein The microphone comprises a first microphone (161) and a second microphone (162); The first microphone (161) is arranged opposite to one end of the rotating hook shaft (140) used for mounting the rotating hook (200) to be tested; The second microphone (162) is arranged at a preset included angle with the rotating hook shaft (140) and faces one end of the rotating hook shaft (140) used for mounting the rotating hook (200) to be tested.

4. The noise and vibration test apparatus according to claim 3, wherein The distance between the first microphone (161) and the rotating hook (200) to be tested is 300 mm; The distance between the second microphone (162) and the rotating hook (200) to be tested is 450 mm; The preset included angle is 45°.

5. The noise and vibration test apparatus according to claim 2, wherein The rotating hook shaft base (130) comprises a base (131), a front bearing base (132) and a rear bearing base (133) arranged on the base (131); The base (131) is mounted on the base plate (110); The rotating hook shaft (140) penetrates through the front bearing base (132) and the rear bearing base (133), one end of the rotating hook shaft (140) extending out of the front bearing base away from the side of the rear bearing base (133) is used for mounting the rotating hook (200) to be tested; The vibration sensor (163) is mounted on the front bearing base (132).

6. The noise and vibration test apparatus according to claim 1, wherein The rotating hook positioning device (150) comprises a mounting base (151) and a positioning hook (152) mounted on the mounting base (151), the mounting base (151) is mounted on the rotating hook shaft base (130), and the positioning hook (152) is used for abutting against the outer hook frame of the rotating hook (200) to be tested.

7. The noise and vibration test apparatus according to claim 1, wherein The noise and vibration testing device further comprises a lubricating device (180), which comprises an oil tank (181) and an adjusting valve (182) connected to the oil tank (181); The oil tank (181) is installed on the base plate (110), and the adjusting valve (182) is connected to the rotating hook shaft seat (130) and used for adjusting the oil supply amount provided to the rotating hook (200) to be tested.

8. The noise and vibration test apparatus according to claim 1, wherein The noise and vibration testing device further comprises a speed sensor (170) installed on the base plate (110) and used for detecting the rotating speed of the rotating hook shaft (140) in real time.

9. A method of calibrating a rotary hook (200) based on the noise and vibration testing apparatus of any one of claims 1 to 8, characterized in that, The method comprises: acquiring noise and vibration parameters from the noise and vibration detector (160); judging whether the noise and vibration parameters meet preset conditions; if yes, confirming that the rotating hook (200) to be tested is qualified; if no, adjusting the gap of the rotating hook (200) to be tested until the noise and vibration parameters meet the preset conditions.

10. The method of bobbin (200) calibration of claim 9, wherein, The noise and vibration parameters comprise noise sound pressure level, noise sharpness, noise loudness, noise jitter, noise roughness and vibration root mean square value; The preset conditions are that any one of the noise sound pressure level, the noise sharpness, the noise loudness, the noise jitter, the noise roughness and the vibration root mean square value is within a respective standard reference range.

Images