A nail detection device

Abstract

The utility model discloses a nail detection device belongs to the field of household appliance automation assembly, solves the problem of the detection accuracy of prior art is poorer, the technical scheme of solving this problem includes detection base, nail feeding mechanism and laser detection mechanism, the laser detection mechanism includes the laser transmitter and laser acceptor of opposite setting on the detection base, the nail feeding mechanism is used for conveying the nail of detection to the detection position on the detection base, the detection position is located the detection laser path between the laser transmitter and laser acceptor, the detection base still is equipped with two light -shields of opposite and interval arrangement, two the light -shields enclose and form the laser channel for laser to pass through, the laser channel is used to accommodate the rod part of the nail of detection. The utility model is used for improving the detection accuracy, reduces the misjudgment.

Description

Technical Field

[0001] This utility model relates to the field of automated assembly of household appliances, and in particular to a nail detection device. Background Technology

[0002] In the field of automated washing machine assembly, nails are critical connecting components. Whether their length meets standards and whether their heads are intact directly affects the reliability of the entire machine assembly and its subsequent performance. Therefore, rapid and accurate defect detection of nails is crucial during the nail supply or production process.

[0003] In existing technologies, photoelectric non-contact detection methods are commonly used: laser emitters and laser receivers are set opposite each other on both sides of the nail feeding track to form a detection optical path; when a nail is fed into this optical path, if its length is insufficient or its head is missing, it cannot completely block the laser beam, and the laser receiver outputs an abnormal signal accordingly, thereby realizing the identification of defects such as short nails and missing nails.

[0004] To suppress interference from stray light from workshop lighting and equipment reflections, existing devices typically use light shields or baffles around the optical path. However, such light-shielding structures only block external light sources and do not effectively constrain the propagation range of the laser beam itself. Because the laser beam emitted by the laser emitter has a certain divergence angle or a large initial emission area, the spot size formed when it reaches the laser receiver is much larger than the cross-section of the nail. In this case, even if the nail is intact, it can only block a very small area in the center of the spot, and the laser receiver still receives most of the laser energy. When the nail has slight defects (such as missing nail tips or slightly shorter length), the change in transmitted light intensity is extremely weak. This slight signal difference not only significantly increases the difficulty of signal processing but is also highly susceptible to electronic noise or threshold drift, leading to misjudgment. Utility Model Content

[0005] The purpose of this invention is to provide a nail detection device that solves the problem of poor detection accuracy in existing technologies, improves detection accuracy, and reduces misjudgments.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a nail detection device, comprising a detection base, a nail feeding mechanism, and a laser detection mechanism. The laser detection mechanism includes a laser emitter and a laser receiver disposed opposite to each other on the detection base. The nail feeding mechanism is used to transport the nail to be detected to a detection position on the detection base. The detection position is located on the detection laser path between the laser emitter and the laser receiver. The detection base is also provided with two light-shielding members disposed opposite to each other and spaced apart. The two light-shielding members enclose a laser channel for the laser to pass through. The laser channel is used to accommodate the shaft of the nail to be detected.

[0007] By adopting the above technical solution, this utility model has the following advantages: The laser channel formed by two spaced-apart light-shielding components not only blocks stray light interference from workshop lighting, equipment reflections, and other environmental sources, preventing it from directly entering the laser receiver and significantly reducing external interference, but also achieves precise constraint on the laser beam propagation range, greatly reducing the spot size reaching the laser receiver and ensuring a good fit with the cross-section of the nail. Under this structure, when a complete nail is placed in the detection laser path, it can fully block the effective laser area, significantly reducing the laser energy received by the laser receiver. However, when the nail has minor defects such as missing tips or slightly shorter lengths, the proportion of unblocked laser light increases significantly, resulting in a clearly identifiable change in transmitted light intensity. Therefore, the signal difference between the qualified and defective states is significantly increased, ensuring not only reliable detection of obvious defects such as short nails and missing nails, but also achieving high-sensitivity identification of minute dimensional deviations, comprehensively improving the accuracy and stability of detection, and providing stronger assurance for the reliability and performance of washing machine assembly.

[0008] Furthermore, the light-shielding member has an arc-shaped concave surface on the side facing the nail, and the arc-shaped concave surface is adapted to a portion of the outer periphery of the nail to be tested in order to avoid the shaft of the nail to be tested.

[0009] By employing the aforementioned technical solution, the arc-shaped concave surface forms a near-surface contact or clearance fit with the cylindrical surface of the nail, providing flexible guidance and ample clearance space during the nail's descent. This significantly reduces the risk of mechanical interference and ensures that the nail passes through the inspection area smoothly and without damage. Simultaneously, because the arc-shaped concave surface closely conforms to the shape of the nail's shaft, there is no need to increase the width of the laser channel. This allows for precise control of the channel's lateral dimensions within a range matching the nail's outer diameter, while ensuring smooth transport. This maximizes the laser blocking effect and improves the signal difference between qualified and defective products.

[0010] Furthermore, the two light-shielding members extend along the direction of the detection laser path, and the inner sidewalls of the two light-shielding members each include an adapter section and a straight section. The adapter section is provided with the arc-shaped concave surface, and the straight section is provided at both ends of the adapter section.

[0011] By employing the aforementioned technical solution, functional zoning and collaborative optimization are achieved by dividing the relatively inner sidewalls of the light-shielding component into an adapting section and a straight section. The adapting section is located in the actual passage area of ​​the nail, and its arc-shaped concave surface matches the outer contour of the nail, ensuring smooth and interference-free passage of the nail while maintaining a good match between the channel width and the nail size. The straight section constitutes the main constraint area in the length direction of the laser channel, minimizing local diffusion or distortion of the light spot in the propagation direction due to irregularities in the light-shielding structure, and ensuring a more regular laser beam shape reaching the laser receiver, facilitating signal processing and difference recognition, and further improving... To improve detection accuracy, the straight sections at both ends and the arc-shaped concave surfaces inside the adapter section are smoothly connected, forming a continuous laser channel with a consistent width. This effectively suppresses the lateral diffusion of the laser beam during propagation. Especially when the adapter section is partially concave to avoid nails, the straight sections at both ends act as optical path guides. The straight sections at both ends and the adapter section form a continuous laser channel. Before entering the adapter section, the laser beam is calibrated by one straight section and then straightened by the other straight section when leaving, minimizing the refraction or scattering of the laser beam caused by the arc-shaped concave surfaces of the adapter section. This ensures that the laser beam acting on the laser receiver is stable and its energy is concentrated.

[0012] Furthermore, the straight sections of the two light-shielding components are parallel to each other and the distance between them is constant.

[0013] The above technical solution ensures that the constant and parallel spacing guarantees that the laser beam is stably confined within a narrow range that matches the outer diameter of the nail rod throughout the entire detection range, thus ensuring that the laser beam passes through in a straight line.

[0014] Furthermore, a positioning hole penetrating the detection base is provided at the detection position. The diameter of the positioning hole is adapted to the outer diameter of the nail rod to be detected. A tapered guide surface is provided at the entrance end of the positioning hole. The diameter of the tapered guide surface gradually decreases from the entrance end of the positioning hole into the positioning hole.

[0015] Using the aforementioned technical solution, the positioning hole provides a precise vertical path for the nail to fall, ensuring that it is always located in the center of the laser detection path, thereby guaranteeing a high degree of repeatability of the beam obstruction state during each detection. Secondly, the conical guide surface at the entrance end forms a flared guide structure, which can quickly correct the posture of the nail even if there is a slight deviation during the nail feeding, allowing it to enter the positioning hole more smoothly and avoiding nail jamming and material blockage as much as possible, thus improving detection efficiency.

[0016] Furthermore, the nail feeding mechanism includes a nail suction component and a conveying channel. The lower end of the conveying channel is connected to the inlet end of the positioning hole, and the upper end of the conveying channel is provided with an inlet for receiving nails. The nail suction component is disposed above the conveying channel and is used to release nails to the inlet of the conveying channel.

[0017] Through the above technical solution, a nail-feeding mechanism including a nail-collecting component and a vertical conveying channel is set up. The lower end of the conveying channel is directly connected to the inlet end of the positioning hole on the detection base, and the upper end is provided with an inlet for receiving nails. The nail-collecting component is set above the conveying channel, which can accurately pick up a single nail and release it to the inlet, realizing the active and controllable supply of single nails and minimizing the need for multiple nails or empty nails. Under the action of gravity, the nail falls stably along the vertical channel, and the inner wall of the channel forms a guiding constraint to ensure that it enters the detection area with a vertical axis and a horizontal cross-section. At the same time, the conveying channel is coaxially connected with the positioning hole, so that the nail can fall accurately into the center of the laser path without turning, ensuring the consistency of posture during detection.

[0018] Furthermore, the height of the light-shielding member is not less than the set detection length of the rod of the nail to be tested.

[0019] With the above technical solution, if the height of the light-shielding component is less than the set detection length of the nail to be tested, there will be a lack of effective light-shielding enclosure in the upper or lower area along the length of the nail. This will make the area susceptible to natural beam divergence, installation gaps, or edge diffraction, resulting in diffused transmitted light intensity distribution and unstable signal response, thus affecting the detection accuracy. By ensuring that the height of the light-shielding component is not less than the set detection length of the nail to be tested, it is possible to ensure that the entire area to be tested, from the nail tip to the nail tail, is within a continuous and closed laser channel formed by the two light-shielding components.

[0020] Furthermore, the nail feeding mechanism vertically transports the nail to the detection position, and the detection base is provided with a mounting notch for installing the laser emitter and laser receiver. The mounting notch has a horizontal opening, and the laser emitter and laser receiver are installed into the mounting notch horizontally through the horizontal opening.

[0021] By setting the installation direction to horizontal, the vertical feeding channel of the nails is avoided as much as possible. This ensures that the nails are not mechanically obstructed during the testing process, and allows for the rapid replacement or maintenance of laser devices without stopping the machine or disassembling the nail feeding mechanism or light-shielding components.

[0022] Furthermore, a stop wall is provided within the mounting notch, and the stop wall is located on the side of the mounting notch away from the lateral opening.

[0023] With the above technical solution, when the laser emitter and laser receiver are pushed into the installation notch through the horizontal opening in the horizontal direction, their front end faces can abut against the stop wall, thereby automatically limiting their installation position in the optical path direction. This avoids the device shifting back and forth due to inconsistent insertion depth or assembly errors, and ensures that the relative distance and optical axis alignment between the laser emitter and laser receiver remain highly consistent after each installation or replacement, significantly improving the repeatability and long-term stability of the detection system.

[0024] Furthermore, the stop wall is provided with through-holes for heat dissipation.

[0025] By using the above technical solution, a through-hole for heat dissipation is opened on the stop wall, which not only retains its core function as an axial positioning reference, but also forms an effective air convection channel or heat radiation outlet without compromising the overall structural rigidity, thus significantly improving the heat dissipation efficiency of the device. Attached Figure Description

[0026] The present invention will be further described below with reference to the accompanying drawings:

[0027] Figure 1 This is a partial structural schematic diagram of the nail detection device in this utility model;

[0028] Figure 2 This is a schematic diagram of the structure of the detection base in this utility model;

[0029] Figure 3 This is a structural schematic diagram of the detection base from another perspective in this utility model;

[0030] Figure 4 This is a cross-sectional view of the detection base in this utility model;

[0031] Figure 5 This is a structural schematic diagram of the detection base from another perspective in this utility model;

[0032] Figure 6 This is a schematic diagram of the nail detection device in this utility model;

[0033] Figure 7 This is a structural schematic diagram of the nail detection device of this utility model from another perspective;

[0034] Figure 8 This is a cross-sectional view of the nail detection device of this utility model;

[0035] Figure 9 This is a cross-sectional view of the nail detection device of this utility model from another perspective;

[0036] In the diagram, 10 is the detection base; 11 is the laser channel; 12 is the positioning hole; 13 is the tapered guide surface; 14 is the mounting notch; 15 is the transverse opening; 16 is the stop wall; 17 is the heat dissipation hole; 20 is the nail feeding mechanism; 21 is the nail suction component; 22 is the conveying channel; 30 is the laser detection mechanism; 31 is the laser emitter; 32 is the laser receiver; 40 is the nail; 50 is the light shield; 51 is the arc-shaped concave surface; 52 is the adapter section; 53 is the straight section; 60 is the support plate; and 61 is the screw. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments.

[0038] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein.

[0039] It should be understood that in the various embodiments of this utility model, the number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this utility model.

[0040] It should be understood that in this invention, "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product or device.

[0041] It should be understood that in this utility model, "multiple" refers to two or more. "And / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, X and / or Y can represent: X alone, X and Y simultaneously, or Y alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "Contains X, Y, and Z", "Contains X, Y, and Z" means that all three X, Y, and Z are contained; "Contains X, Y, or Z" means that one of X, Y, and Z is contained; "Contains X, Y, and / or Z" means that any one, two, or three of X, Y, and Z are contained.

[0042] The technical solution of this utility model will be described in detail below with specific embodiments. The following specific embodiments can be selected to be combined or substituted with each other according to the actual situation, and the same or similar concepts or processes may not be described again in some embodiments.

[0043] like Figures 1 to 9 As shown, this utility model provides a nail detection device, including a detection base 10, a nail feeding mechanism 20, and a laser detection mechanism 30. The laser detection mechanism 30 includes a laser emitter 31 and a laser receiver 32 disposed opposite to each other on the detection base 10. The nail feeding mechanism 20 is used to transport the nail 40 to be detected to the detection position on the detection base 10. The detection position is located on the detection laser path between the laser emitter 31 and the laser receiver 32. The detection base 10 is also provided with two light-shielding members 50 disposed opposite to each other and spaced apart. The two light-shielding members 50 enclose a laser channel 11 for the laser to pass through. The laser channel 11 is used to accommodate the rod part of the nail 40 to be detected.

[0044] The laser channel 11, formed by two spaced-apart light-shielding elements 50, not only blocks stray light interference from workshop lighting, equipment reflections, and other environmental sources, preventing it from directly entering the laser receiver 32 and significantly reducing external interference, but also precisely constrains the laser beam propagation range, greatly reducing the spot size reaching the laser receiver 32 and ensuring a good fit with the cross-section of the nail 40. With this structure, when the intact nail 40 is placed horizontally in the detection laser path, it effectively blocks the effective laser area, significantly reducing the laser energy received by the laser receiver 32. Conversely, when the nail 40 has minor defects such as missing tips or slightly shorter lengths, the proportion of unblocked laser light increases significantly, resulting in a clearly identifiable change in transmitted light intensity. As a result, the signal difference between the qualified and defective states is significantly increased, which not only ensures the reliable detection of obvious defects such as short nails and missing nails, but also achieves high-sensitivity identification of minute dimensional deviations. This comprehensively improves the accuracy and stability of the detection, and can be widely used in automated assembly lines for home appliances, automobiles, motors, etc. Especially in scenarios such as washing machine drum assembly where the integrity of fasteners is strictly required, it can effectively avoid assembly misalignment, abnormal operating noise, or structural failure caused by short nails and missing nails, providing strong protection for the reliability and performance of the whole machine.

[0045] It should be noted that the light-shielding components 50 are located on both sides of the detection position. The lateral width of the laser channel 11 is slightly larger than the outer diameter of the rod of the nail 40 to be detected. This ensures that when the nail 40 passes through the detection position, there is a small gap between the outer periphery of its rod and the light-shielding components 50 on both sides, which are set at intervals. This ensures that the nail 40 will not mechanically interfere with or scratch the light-shielding components 50 during its fall, thus ensuring smooth transport. On the other hand, by controlling the lateral width of the laser channel 11 to be only slightly larger than the outer diameter of the rod of the nail 40, the lateral diffusion of the laser beam can be effectively constrained, so that the spot size matches the height of the cross-section of the rod of the nail 40. This results in a significant change in transmitted light intensity when the nail 40 has defects, improving detection sensitivity and discrimination reliability.

[0046] It should be noted that the laser detection mechanism 30 operates based on the principle of light blocking: the laser emitter 31 continuously emits a horizontal laser beam, and the laser receiver 32 receives the laser beam in real time and outputs a corresponding light intensity signal. When no nail 40 is located at the detection position, the laser passes completely through the laser channel 11, and the laser receiver 32 outputs a high-level signal; when the nail 40 to be detected is transported to the detection position and placed horizontally in the laser path, the rod of the nail 40 will block part or all of the laser beam, causing the light intensity received by the laser receiver 32 to decrease, and the output signal to decrease accordingly. The control system compares the signal strength or change output by the laser receiver 32 with a preset threshold to determine whether the nail 40 has a rod, whether its length meets the standard, or whether it is defective. For example, when the nail 40 to be tested is a qualified product: its length reaches the set detection length, its rod completely covers the effective height range of the laser channel 11 in the vertical direction, the laser is fully blocked, and the laser receiver 32 outputs a stable low level. However, when the rod of the nail 40 is too short due to manufacturing defects or wear, its bottom end cannot reach the lower area of ​​the laser channel 11, causing the laser in that area to be directly transmitted to the laser receiver 32 without being blocked, resulting in a total light intensity that is significantly higher than that of the qualified state. By comparing the current signal with the preset threshold, the control system can accurately determine that the nail 40 is a short nail and trigger rejection or an alarm.

[0047] It should be noted that the light-shielding component 50 is integrally formed with the detection base 10, ensuring the long-term stability of the geometric dimensions of the laser channel 11 and effectively guaranteeing the detection accuracy.

[0048] If the side of the light-shielding member 50 facing the nail 40 is a flat or right-angled inner wall, then when the nail 40 falls vertically through the detection position, its rod will make point or line contact with the rigid straight surface of the light-shielding member 50. On the one hand, this rigid contact is very prone to jamming, scratching, or even rebounding due to slight deviations in the falling posture of the nail 40, surface burrs, or vibrations, especially under high-speed continuous nail feeding conditions, significantly increasing the conveying failure rate; on the other hand, to avoid nail jamming, designers are often forced to increase the spacing between the light-shielding members 50, making the width of the laser channel 11 much larger than the outer diameter of the nail 40, thereby reducing the proportion of the nail 40 blocking the laser beam and reducing the detection sensitivity. Therefore, in this application, the light-shielding member 50 has an arc-shaped concave surface 51 on the side facing the nail 40. The arc-shaped concave surface 51 is adapted to a portion of the outer periphery of the nail 40 to avoid the rod of the nail 40, providing flexible guidance and sufficient avoidance space during the falling process of the nail 40, significantly reducing the risk of mechanical interference, and ensuring that the nail 40 passes through the detection area smoothly and without damage as much as possible. At the same time, since the arc-shaped concave surface 51 can adapt to the shape of the rod of the nail 40, it is not necessary to increase the width of the laser channel 11 excessively. Under the premise of ensuring smooth delivery, the lateral dimension of the channel can be precisely controlled within a range that matches the outer diameter of the rod of the nail 40, thereby maximizing the laser blocking effect and improving the signal difference between qualified and defective products.

[0049] If the light-shielding member 50 uses an arc-shaped concave surface 51 throughout to avoid the nail 40, there is a lack of effective constraint on the laser beam outside the arc-shaped area, especially at the entrance and exit of the laser channel 11. The laser is prone to local widening at both ends of the laser channel 11 due to divergence or edge diffraction, resulting in uneven light spots and weakening the blocking contrast. Therefore, in this application, the two light-shielding members 50 extend along the direction of the detection laser path. The inner sidewalls of the light-shielding members 50 each include an adapter section 52 and a straight section 53. The adapter section 52 is provided with an arc-shaped concave surface 51. The straight sections 53 of the two light-shielding members 50 are parallel to each other and the spacing is constant, realizing functional zoning and collaborative optimization. The adapter section 52 is located at... The arc-shaped concave surface 51 of the area through which the nail 40 actually passes matches the outer contour of the nail 40. This ensures that the nail 40 passes smoothly and without interference while maintaining a good match between the channel width and the size of the nail 40. The straight section 53 constitutes the main constraint area in the length direction of the laser channel 11. Its constant and parallel spacing ensures that the laser beam is stably confined within a narrow range that matches the outer diameter of the nail 40 throughout the entire detection range. This minimizes the local diffusion or distortion of the light spot in the propagation direction due to the irregularity of the light-shielding structure, and ensures that the laser beam reaching the laser receiver 32 has a more regular shape, which facilitates signal processing and difference recognition, and further improves the detection accuracy.

[0050] Since the nail 40 only passes through the adapter section 52, while the laser beam needs to pass through the straight section 53 and the adapter section 52, if there is a lack of structural continuity before and after the adapter section 52, the laser beam is prone to local divergence or shift due to edge diffraction, structural abrupt changes or assembly gaps when entering or leaving the adapter area, resulting in the light spot expanding or deforming at the receiving end. Therefore, in this application, both ends of the adapter section 52 are provided with straight sections 53. The straight sections 53 at both ends are smoothly connected with the arc-shaped concave surface 51 on the inner side of the adapter section 52, forming a continuous laser channel 11 with consistent width. This effectively suppresses the lateral diffusion of the laser beam during propagation. Especially when the adapter section 52 is partially concave to avoid the nail 40, the straight sections 53 at both ends play a guiding role in the optical path. The straight sections 53 at both ends and the adapter section 52 form a continuous laser channel 11. Before entering the adapter section 52, the laser is calibrated by one end of the straight section 53 and straightened by the other end of the straight section 53 when leaving. This avoids the laser beam refraction or scattering caused by the arc-shaped concave surface 51 of the adapter section 52 as much as possible, and ensures that the laser beam acting on the laser receiver 32 is stable and the energy is concentrated.

[0051] Furthermore, the two straight segments 53 of the same light-shielding element 50 are collinearly arranged along the extension direction of the detection laser path, that is, the two straight segments 53 are located on the same straight line without any steps, offsets, or angular changes between them. This ensures that the laser channel 11 maintains a constant lateral width in the area covered by the straight segments 53, thereby forming a continuous and uniform constraint on the laser beam. This minimizes the risk of spot distortion or edge diffraction caused by abrupt changes in the contour of the laser channel 11, effectively guaranteeing the stability of the light intensity distribution and the repeatability of the detection signal.

[0052] If the height of the light-shielding member 50 is less than the set detection length of the rod of the nail 40 to be tested, there will be a lack of effective light-shielding in the upper or lower area along the length of the nail 40. This will make the area susceptible to natural beam divergence, installation gaps, or edge diffraction, resulting in diffused transmitted light intensity distribution and unstable signal response, which will affect the accuracy of the test. Therefore, in this application, the height of the light-shielding member 50 is not less than the set detection length of the rod of the nail 40 to be tested, so as to ensure that the entire area to be tested from the nail tip to the nail tail is within the continuous and closed laser channel 11 formed by the two light-shielding members 50.

[0053] Furthermore, a positioning hole 12 penetrating the detection base 10 is provided at the detection position. The diameter of the positioning hole 12 is adapted to the outer diameter of the rod of the nail 40 to be detected. The positioning hole 12 provides a precise vertical drop channel for the nail 40, ensuring that it is always located in the center area of ​​the laser detection path, i.e., the detection position, thereby ensuring a high degree of repeatability of the beam obstruction state during each detection. Secondly, a tapered guide surface 13 is provided at the entrance end of the positioning hole 12. The diameter of the tapered guide surface 13 gradually decreases from the entrance end of the positioning hole 12 into the positioning hole 12. Even if there is a slight deviation when the nail 40 is conveyed, the posture can be quickly corrected by the guiding effect of the tapered guide surface 13, and the nail can enter the positioning hole 12 more smoothly, avoiding nail jamming and material blockage as much as possible, and improving detection efficiency.

[0054] In existing technologies, nails 40 are often fed directly into the detection area via a vibratory feeder in conjunction with an inclined slide or an open hopper. This lacks active control and attitude constraint over individual nails 40. During the conveying process, nails 40 often roll, tilt, or even become inverted, causing their cross-section to be unable to be perpendicular to the laser path when they enter the detection position. This results in abnormal occlusion area, leading to misjudgment or missed detection. At the same time, high-speed nail feeding can easily lead to multiple nails stacking, jamming, or empty nails, making it difficult to ensure a stable supply of individual nails. Furthermore, if the conveying path and the detection and positioning structure are not precisely connected, there will be a lateral offset space during the falling of the nail 40, which will not be reliably centered on the laser beam. This will result in inconsistent occlusion states for each detection, poor signal repeatability, and serious impact on detection accuracy and system reliability. Therefore, in this application, the nail feeding mechanism 20 includes a nail suction component 21 and a conveying channel 22. The lower end of the conveying channel 22 is connected to the entrance end of the positioning hole 12, and the upper end of the conveying channel 22 is provided with an inlet for receiving the nail 40. The nail suction component 21 is located above the conveying channel 22 and is used to release the nail 40 to the inlet of the conveying channel 22. It can pick up a single nail 40 more accurately and release it to the inlet, realizing the active and controllable supply of a single nail 40 and avoiding multiple nails or empty nails as much as possible. The nail 40 falls steadily along the vertical channel under the action of gravity. The inner wall of the channel forms a guiding constraint on it, ensuring that it enters the detection area with a vertical axis and a horizontal cross-section. At the same time, the conveying channel 22 is coaxially connected with the positioning hole 12, so that the nail 40 can fall accurately into the center of the laser path without turning, ensuring the consistency of posture during detection.

[0055] It should be noted that, in one embodiment, the nail-collecting component 21 can be an electromagnetic suction head, which is mounted above the conveying channel 22 via a bracket and connected to a lifting cylinder. During operation, the electromagnetic suction head descends to the nail-supply position, is energized to attract the ferrous nail 40, then rises and moves horizontally above the conveying channel 22. After power is cut off, the nail 40 falls into the conveying channel 22 under gravity. In another embodiment, the nail-collecting component 21 can be a vacuum nozzle, connected to a vacuum generator via a negative pressure pipeline, suitable for picking up and releasing non-magnetic nails 40.

[0056] Furthermore, due to the relatively long length of the conveying channel 22, the nail 40 may still fail to accurately align with the positioning hole 12 during its descent under gravity alone due to tilting or slight wobbling, resulting in jamming or conveying failure. To improve the reliability of nail supply, the device can also be operated as follows: the nail suction component 21 is extended downward along the conveying channel 22 until the nail 40 it carries is accurately pushed to the entrance end of the positioning hole 12, and then the nail 40 is released so that it falls directly into the positioning hole 12.

[0057] The nail feeding mechanism 20 vertically transports the nail 40 to the detection position. The detection base 10 is provided with a mounting notch 14 for mounting the laser emitter 31 and the laser receiver 32. If the laser emitter 31 and the laser receiver 32 are mounted at the top or bottom, not only is there a high risk of structural interference, but the nail feeding process must be interrupted or even the nail feeding mechanism 20 must be disassembled during maintenance. Therefore, in this application, the mounting notch 14 is provided with a horizontal opening 15. The laser emitter 31 and the laser receiver 32 are installed into the mounting notch 14 horizontally through the horizontal opening 15, avoiding the vertical conveying channel 22 of the nail 40 as much as possible. This ensures that the nail 40 is not mechanically obstructed during the detection process and allows for quick replacement or maintenance of the laser device without stopping the machine or disassembling the nail feeding mechanism 20 or the light shield 50.

[0058] Furthermore, a stop wall 16 is provided within the mounting notch 14, located on the side of the mounting notch 14 away from the transverse opening 15. When the laser emitter 31 and the laser receiver 32 are pushed into the mounting notch 14 horizontally through the transverse opening 15, their front ends can abut against the stop wall 16, thereby automatically limiting their installation position in the optical path direction. This minimizes the risk of device misalignment due to inconsistent insertion depth or assembly errors, ensuring that the relative distance and optical axis alignment between the laser emitter 31 and the laser receiver 32 remain highly consistent after each installation or replacement, significantly improving the repeatability and long-term stability of the detection system.

[0059] It should be noted that the housing structure of the laser emitter 31 and the laser receiver 32 is set as an integral structure. When this integral structure is pushed into the mounting notch 14 horizontally from the transverse opening 15, its front end face abuts against the stop wall 16, achieving initial axial positioning. To further improve the installation stability and prevent the components from loosening due to vibration during equipment operation, a support plate 60 is provided below the integral structure. The support plate 60 is fixedly connected to the detection base 10 by screws 61, thereby reliably pressing and fixing the laser emitter 31 and the laser receiver 32 in the mounting notch 14. This structure facilitates quick assembly and disassembly, as the laser emitter 31 and the laser receiver 32 can be pulled out horizontally simply by loosening the screws 61, while also ensuring the positional stability of the laser emitter 31 and the laser receiver 32 during long-term operation.

[0060] Since the stop wall 16 is located at the inner end of the mounting notch 14, closely attached to the rear housing of the laser emitter 31 or laser receiver 32, a closed structure would hinder the conduction of heat from the device's interior to the outside of the base, leading to localized temperature rise. This temperature increase could not only cause laser wavelength drift and output power fluctuations, but also affect the dark current and sensitivity of the laser receiver 32, resulting in signal drift or even misjudgment. Therefore, in this application, the stop wall 16 is provided with a through-hole heat dissipation hole 17, which retains its core function as an axial positioning reference while forming an effective air convection channel or heat radiation outlet without compromising the overall structural rigidity, significantly improving the device's heat dissipation efficiency.

[0061] In addition to the preferred embodiments described above, there are other embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection claimed by this utility model.

Claims

1. A nail detection device, characterized in that, The device includes a detection base, a nail feeding mechanism, and a laser detection mechanism. The laser detection mechanism includes a laser emitter and a laser receiver disposed opposite to each other on the detection base. The nail feeding mechanism is used to transport the nail to be detected to a detection position on the detection base. The detection position is located on the detection laser path between the laser emitter and the laser receiver. The detection base is also provided with two light-shielding members disposed opposite to each other and spaced apart. The two light-shielding members enclose a laser channel for the laser to pass through. The laser channel is used to accommodate the shaft of the nail to be detected.

2. The nail detection device according to claim 1, characterized in that, The light-shielding component has an arc-shaped concave surface on the side facing the nail, and the arc-shaped concave surface is adapted to a portion of the outer periphery of the nail to be tested in order to avoid the shaft of the nail to be tested.

3. The nail detection device according to claim 2, characterized in that, The two light-shielding members extend along the direction of the detection laser path. The inner sidewalls of the two light-shielding members each include an adapter section and a straight section. The adapter section is provided with the arc-shaped concave surface, and the straight section is provided at both ends of the adapter section.

4. The nail detection device according to claim 3, characterized in that, The straight sections of the two light-shielding elements are parallel to each other and the distance between them is constant.

5. The nail detection device according to claim 1, characterized in that, The detection position is provided with a positioning hole that penetrates the detection base. The diameter of the positioning hole is adapted to the outer diameter of the nail rod to be detected. The entrance end of the positioning hole is provided with a tapered guide surface. The diameter of the tapered guide surface gradually decreases from the entrance end of the positioning hole into the positioning hole.

6. The nail detection device according to claim 5, characterized in that, The nail feeding mechanism includes a nail suction component and a conveying channel. The lower end of the conveying channel is connected to the inlet end of the positioning hole, and the upper end of the conveying channel is provided with an inlet for receiving nails. The nail suction component is disposed above the conveying channel and is used to release nails to the inlet of the conveying channel.

7. The nail detection device according to claim 1, characterized in that, The height of the light-shielding component is not less than the set detection length of the rod of the nail to be tested.

8. The nail detection device according to claim 1, characterized in that, The nail feeding mechanism vertically transports the nail to the detection position. The detection base is provided with a mounting notch for installing the laser emitter and laser receiver. The mounting notch has a horizontal opening, and the laser emitter and laser receiver are installed into the mounting notch horizontally through the horizontal opening.

9. The nail detection device according to claim 8, characterized in that, A stop wall is provided within the mounting notch, and the stop wall is located on the side of the mounting notch away from the lateral opening.

10. The nail detection device according to claim 9, characterized in that, The stop wall is provided with through-holes for heat dissipation.

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