Surface coating quality detection system special for copper pipe drawing die

Abstract

The invention relates to the technical field of copper pipe forming, in particular to a surface coating quality detection system special for a copper pipe drawing die, which comprises a bottom base, a drawing die body, a detection integration part and a clamping tool, the clamping tool is used for clamping a drawing die body; a rotary driving part is arranged at the bottom of the clamping tool; an axial displacement module is arranged at the bottom of the detection integration part; the detection integration part comprises a test core rod; the diameter of the test core rod is matched with that of a sizing belt of the drawing die body; the outer side of the testing core rod is sleeved with a conical reducing head, and the conical reducing head is matched with the working conical area of the drawing die body; an inner penetrating eddy current probe is arranged at the head end of the testing core rod, one end of the testing core rod is fixedly connected with a fixing base, and a fixing plate is arranged at one end of the fixing base.

Description

Technical Field

[0001] This invention relates to the technical field of copper tube forming, and in particular to a surface coating quality inspection system specifically for copper tube drawing dies. Background Technology

[0002] Copper tube drawing dies are the core components of the copper tube forming process. The inner hole of the die core is an important structure for copper tube drawing and forming. It is divided into the inlet cone area, working cone area, sizing zone and outlet cone area along the axial direction. The working cone area is the area for plastic reduction of copper tube diameter, and the sizing zone is the area for dimensional calibration and surface forming. It usually needs to be coated with a wear-resistant and highly adhesive coating to extend its service life.

[0003] Currently, some manufacturers use copper tubes directly as the test medium in their drawing die coating testing process, resulting in high testing costs. Furthermore, the copper tubes cannot be reused after drawing tests, leading to poor practicality. Other manufacturers use mandrels for insertion testing, but this is often difficult to achieve comprehensive and uniform testing of the working cone area and sizing zone within a limited length. Using excessively long mandrels compromises coaxiality and can cause mandrel wobbling. Moreover, when testing the coating quality of the inner hole using a probe after the initial test, the inner hole center needs to be repositioned, which is cumbersome, inefficient, and prone to positioning errors, affecting testing accuracy.

[0004] Therefore, in order to ensure the reusability of the inspection structure, the comprehensiveness and coaxiality of the inspection of the working cone area and sizing zone of the mold, and to avoid problems such as secondary positioning probes, it is necessary to provide a surface coating quality inspection system specifically for copper tube drawing dies. Summary of the Invention

[0005] The purpose of this invention is to provide a surface coating quality inspection system specifically for copper tube drawing dies, which can detect the circumferential adhesion of the coating inside the die within a limited test stroke.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a surface coating quality inspection system for copper tube drawing dies, comprising a bottom base, a drawing die body, an inspection integration unit, and a clamping fixture; The clamping fixture is used to clamp the drawing die body; The bottom of the clamping fixture is provided with a rotary drive unit; An axial displacement module is provided at the bottom of the detection integration unit; The detection integration unit includes a test core rod; The diameter of the test mandrel is adapted to the sizing band of the drawing die body; A tapered variable diameter head is sleeved on the outside of the test mandrel, and the tapered variable diameter head is adapted to the working cone area of ​​the drawing die body; An internal eddy current probe is installed at the head end of the test mandrel.

[0007] As a preferred embodiment of the present invention, a fixed base is fixedly connected to one end of the test mandrel, a fixed plate is provided at one end of the fixed base, and a guide bracket is provided on one side of the fixed plate. The guide bracket is driven to move by an axial displacement module. A number of guide pins are fixedly connected to one side of the fixed plate. The guide pins pass through and are slidably fitted with guide sleeves. The guide sleeves pass through the vertical plate of the guide bracket and are fixedly connected to it. A pressure sensor and a spring assembly are installed between the fixed plate and the vertical plate of the guide bracket.

[0008] In a preferred embodiment of the present invention, the axial displacement module includes a slider assembly, which is disposed at the bottom of the guide bracket; The bottom of the slider assembly is slidably fitted with a guide rail, and a guide rail pad is provided at the bottom of the guide rail, and the guide rail pad is fixed to the upper surface of the bottom base. The bottom of the guide bracket is provided with a support base, the center of the support base is provided with a sleeve hole, a nut seat is provided in the sleeve hole, and a lead screw body is provided inside the nut seat. The lead screw body is provided with bearing seats at both ends, and the bearing seats are bolted to the bottom base.

[0009] As a preferred embodiment of the present invention, a photoelectric sensor group is provided on the upper surface of the bottom base, and the photoelectric sensor group is arranged along one side of the guide rail; At least one light-shielding plate is provided on one side of the guide bracket, and the light-shielding plate is adapted to the photoelectric sensor group.

[0010] As a preferred embodiment of the present invention, the clamping fixture includes a three-jaw chuck, one end of which is rotatably connected to a fixed support, and a base plate is fixedly connected to the bottom of the fixed support, the base plate being bolted to the bottom base; Both the three-jaw chuck and the fixed support have through holes at their centers to accommodate the test mandrel. One end of the three-jaw chuck is fixedly connected to a gear 1, and the bottom of the gear 1 is meshed with a gear 2, which is driven to rotate by a rotary drive unit.

[0011] In a preferred embodiment of the present invention, the rotary drive unit includes an extension shaft, which is connected to one end of the lead screw body near the clamping fixture, and one end of the extension shaft is connected to a gear.

[0012] As a preferred embodiment of the present invention, the rotary drive unit includes a motor assembly, the motor assembly is fixed to the bottom of the base, the output end of the motor assembly is provided with a pulley one, and a pulley two is connected to one side of the pulley one, the pulley two being connected to the lead screw body.

[0013] As a preferred embodiment of the present invention, the support base and the nut base are rotatably connected and an automatic locking mechanism is provided between them; The automatic locking mechanism includes an electromagnetic coil, a locking pin, and a lock hole; The electromagnetic coil is fixed to the bottom of the support base by an L-shaped bracket. The locking pin is installed inside the electromagnetic coil and moves axially under the action of electromagnetic force. The locking holes are evenly opened around the outer side wall of the nut seat. When the locking pin extends, it is inserted into the locking hole.

[0014] In a preferred embodiment of the present invention, the tapered variable diameter head is fixedly connected to the end of the test mandrel.

[0015] In a preferred embodiment of the present invention, the tapered variable diameter head is slidably fitted to the outside of the test mandrel, a retaining ring is fixedly connected to the end of the test mandrel, and a spring is sleeved on the outside of the test mandrel, with the two ends of the spring connected to the retaining ring and the tapered variable diameter head respectively. The test mandrel has straight keyways on both sides, and the tapered variable diameter head has a straight key axially arranged inside, which slides along the straight keyway.

[0016] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: The present invention uses a test mandrel and a tapered variable diameter head to replace the real copper tube as the test medium, which will not cause deformation damage, can be repeatedly recycled, avoids the high cost of copper tube consumables and the inability to be reused, improves the overall practicality and saves costs. By setting a tapered reducing head to fit the working cone area and a test mandrel to fit the sizing zone, the plastic forming process of copper tubes is simulated. Coating inspection is performed on areas such as the working cone area and the sizing zone. Combined with the combined motion of the rotation of the drawing die body and the axial feed of the test mandrel, the core working area can be uniformly covered within a limited test length. The inspection position is highly matched with the actual working state of the drawing die body, avoiding local missed inspections. Furthermore, the test mandrel has good coaxiality, avoiding wobbling and offset problems, further improving the stability and accuracy of the inspection. Attached Figure Description

[0017] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0018] In the attached diagram: Figure 1This is a schematic diagram of the overall structure of the coating quality inspection system of the present invention; Figure 2 This is a cross-sectional schematic diagram of the drawing die of the present invention; Figure 3 This is a schematic diagram of the tapered variable diameter head fixing of the present invention; Figure 4 This is a partial three-dimensional schematic diagram of the present invention; Figure 5 yes Figure 4 A magnified view of a portion of region A; Figure 6 This is a three-dimensional schematic diagram of the rotary drive unit of the present invention; Figure 7 This is a three-dimensional schematic diagram of the clamping fixture of the present invention; Figure 8 This is a schematic diagram of the sliding of the tapered variable diameter head of the present invention; Figure 9 This is a three-dimensional schematic diagram of the automatic locking mechanism of the present invention; In the diagram: 1. Detection integration unit; 101. Test mandrel; 102. Tapered reducing head; 103. Fixing base; 104. Fixing plate; 105. Guide bracket; 106. Guide pin; 107. Guide sleeve; 108. Retaining ring; 109. Spring component; 110. Straight keyway; 2. Axial displacement module; 201. Slider assembly; 202. Guide rail; 203. Guide rail pad; 204. Support seat; 205. Nut seat; 206. Lead screw body; 207. Bearing seat; 208. Extension shaft; 209. Bearing sleeve; 3. Clamping fixture; 301. Three-jaw chuck; 302. Fixed support; 303. Base plate; 304. Gear 1; 305. Gear 2; 4. Pressure sensor; 401. Electromagnetic coil; 402. Locking pin; 403. Locking hole; 404. L-shaped bracket; 5. Drawing die body; 501. Working cone area; 502. Sizing zone; 6. Internal eddy current probe; 7. Bottom base; 8. Motor assembly; 801. Pulley one; 802. Pulley two; 9. Photoelectric sensor assembly; 901. Light-shielding sheet. Detailed Implementation

[0019] The following disclosure provides many different embodiments or examples for implementing different structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0020] Please see Figure 1-9 The present invention provides a technical solution: a surface coating quality inspection system for copper tube drawing dies, comprising a bottom base 7, a drawing die body 5, an inspection integration part 1, and a clamping fixture 3; Clamping fixture 3 is used to clamp the drawing die body 5; The bottom of the clamping fixture 3 is provided with a rotary drive unit; An axial displacement module 2 is provided at the bottom of the detection integration unit 1; The detection integration unit 1 includes a test core 101; The diameter of the test mandrel 101 is adapted to the sizing band 502 of the drawing die body 5; A tapered variable diameter head 102 is sleeved on the outer side of the test mandrel 101, and the tapered variable diameter head 102 is adapted to the working cone area 501 of the drawing die body 5. An internal eddy current probe 6 is installed at the head end of the test mandrel 101.

[0021] Specifically, the operator inserts the drawing die body 5 into the clamping fixture 3, corresponding to the detection integration unit 1, to achieve coaxial clamping and positioning. Then, the axial displacement module 2 drives the detection integration unit 1 to feed axially, causing the test mandrel 101 to extend into the inner hole of the drawing die body 5. The test mandrel 101 contacts the sizing belt 502, and then the tapered reducing head 102 contacts the working cone area 501. At the same time, the rotation drive unit drives the drawing die body 5 to rotate, so that the test mandrel 101 and the inner hole of the die form a compound relative motion of axial feeding and circumferential rotation, thereby simultaneously detecting the working die body 5. The coating adhesion and wear resistance of the working cone area 501 and the sizing belt 502 are tested. After the test is completed, the axial displacement module 2 drives the test mandrel 101 to axially reset and exit. The inner eddy current probe 6 at the head end of the mandrel moves to the detection position of the working cone area 501 and the sizing belt 502 with the reset action. At this time, the drawing die body 5 remains in a rotating state. The inner eddy current probe 6 is activated to perform 360° full circumferential eddy current detection on the coating of the working cone area 501 and the sizing belt 502 in the inner hole of the die. The coating thickness, wear degree and peeling defects are obtained in real time, and the entire coating quality inspection process is completed. In this embodiment, the test mandrel 101 and the tapered reducing head 102 are used instead of the real copper tube as the test medium. This will not cause deformation or damage and can be repeatedly recycled, avoiding the high cost of copper tube consumables and the inability to reuse them. This improves the overall practicality and saves costs. Furthermore, by setting a tapered reducing head 102 to fit the working cone area 501 and a test mandrel 101 to fit the sizing band 502, the plastic forming process of the copper tube is simulated. Coating inspection is performed on areas such as the working cone area 501 and the sizing band 502. Combined with the combined motion of the rotation of the drawing die body 5 and the axial feed of the test mandrel 101, the core working area can be uniformly covered within a limited test length. The inspection position is highly matched with the actual working state of the drawing die body 5, avoiding local missed inspections. Moreover, the test mandrel 101 has good coaxiality, avoiding shaking and offset problems, further improving the stability and accuracy of the inspection. Furthermore, the internal eddy current probe 6 is integrated into the head end of the test mandrel 101. After the test is completed, it is reset and withdrawn with the test mandrel 101, and directly displaced to the detection point. There is no need to re-align the center of the inner hole, avoiding secondary positioning errors, simplifying the operation process, and improving detection efficiency and accuracy. Furthermore, by integrating the tapered variable diameter head 102, the internal eddy current probe 6, and the test mandrel 101 into one unit, there is no need to set up separate test components and detection probe installation structures, which further simplifies the overall system structure layout and reduces assembly steps and component wear. At the same time, through the integrated structure, the testing of the working cone area 501 and the sizing zone 502 can be realized simultaneously. With the rotation of the drawing die body 5, the full circumference coating inspection can be completed. The structural design is simple and reasonable, and the operation is efficient. Preferably, the bottom base 7 is made of steel as a reference for system installation, ensuring the installation flatness and coaxiality of the clamping fixture 3 and the axial displacement module 2, and having sufficient rigidity to offset vibrations during the detection process and avoid affecting the detection accuracy. Preferably, the outer diameter of the test mandrel 101 is adapted to the sizing belt 502, and the tapered reducing head 102 is coaxially sleeved on the outside of the test mandrel 101, and its tapered surface angle and size are adapted to the working tapered area 501. Preferably, the internal eddy current probe 6 is embedded in the head end of the test mandrel 101 and is coaxial with the mandrel. A wiring channel is reserved inside the test mandrel 101 for the signal transmission of the probe.

[0022] Based on the above embodiments, a fixed base 103 is fixedly connected to one end of the test mandrel 101, a fixed plate 104 is provided at one end of the fixed base 103, and a guide bracket 105 is provided on one side of the fixed plate 104. The guide bracket 105 is driven to move by the axial displacement module 2. A number of guide pins 106 are fixedly connected to one side of the fixed plate 104. The guide pins 106 pass through and are slidably fitted with guide sleeves 107. The guide sleeves 107 pass through the vertical plate of the guide bracket 105 and are fixedly connected to it. A pressure sensor 4 and a spring assembly are provided between the fixed plate 104 and the vertical plate of the guide bracket 105.

[0023] Specifically, when the test mandrel 101 and the tapered variable diameter head 102 successively contact the sizing belt 502 and the working cone area 501, the spring assembly is compressed, and the pressure sensor 4 monitors the axial reaction force in real time. During this process, the guide pin 106 slides linearly along the guide sleeve 107 to ensure the coaxiality of the test mandrel 101. In this embodiment, the spring assembly and pressure sensor 4 work together to form an elastic floating structure, which can monitor and stably control the frictional pressure between the test mandrel 101 and the inner hole of the mold in real time, avoiding damage to the coating due to excessive pressure or failure of detection due to insufficient pressure, achieving constant pressure and standardized testing, and improving the accuracy of the test results. Furthermore, the elastic floating structure can achieve micro-axial adaptive compensation, which is suitable for different dimensional tolerances and assembly deviations of the inner hole of the mold, avoids scratching of the mold coating or jamming of the test mandrel 101 caused by rigid insertion, improves the stability of equipment operation, and protects the drawing die body 5 and the inner eddy current probe 6. Preferably, the fixed base 103 and the guide bracket 105 are bolted together, which facilitates disassembly and assembly and makes it easier to replace, maintain and test the integrated unit 1 later. Preferably, the guide bracket 105 is an L-shaped vertical rigid bracket, the bottom of which is connected to the axial displacement module 2, and the axial displacement module 2 directly drives the whole to perform axial linear feed and reset movements. Preferably, the two ends of the spring assembly abut against the fixed plate 104 and the vertical plate of the guide bracket 105 respectively, providing pre-tightening elastic force; and the detection end face of the pressure sensor 4 is in contact with the fixed plate 104 to collect the transmitted axial pressure signal in real time.

[0024] Based on the above embodiments, the axial displacement module 2 includes a slider assembly 201, which is disposed at the bottom of the guide bracket 105; The bottom of the slider assembly 201 is slidably fitted with a guide rail 202, and a guide rail pad 203 is provided at the bottom of the guide rail 202. The guide rail pad 203 is fixed to the upper surface of the bottom base 7. The bottom of the guide bracket 105 is provided with a support base 204, the center of the support base 204 is provided with a sleeve hole, a nut seat 205 is provided in the sleeve hole, and a lead screw body 206 is provided inside the nut seat 205. The lead screw body 206 has bearing seats 207 at both ends, and the bearing seats 207 are bolted to the bottom base 7.

[0025] Specifically, the lead screw body 206 rotates, which drives the support seat 204 and guide bracket 105 to feed axially through the nut seat 205, and the slider assembly 201 slides synchronously linearly along the guide rail 202; In this embodiment, the combination of a lead screw and nut mechanism and a linear guide rail improves the axial feed and reset positioning accuracy, further ensuring that the inner eddy current probe 6 accurately stops at the working cone area 501 and the sizing zone 502 detection station; Furthermore, the slider assembly 201 and the guide rail 202 form a rigid linear guide pair, which restricts the linear movement of the guide bracket 105 throughout the entire process, avoiding deviation or up-and-down swaying, and further ensuring the coaxiality of the test mandrel 101 and the inner hole of the mold, resulting in more uniform testing. Preferably, the support base 204 is located at the center of the bottom of the guide bracket 105, and a coaxial sleeve hole is opened in the center of the support base 204. The nut seat 205 is installed in the sleeve hole. The lead screw body 206 is threadedly engaged with the nut seat 205. The two ends of the lead screw body 206 are rotatably supported by bearing seats 207. The bearing seats 207 are fixedly connected to the bottom base 7 by bolts to form a stable rotational support structure.

[0026] Based on the above embodiments, a photoelectric sensor group 9 is provided on the upper surface of the bottom base 7, and the photoelectric sensor group 9 is provided along one side of the guide rail 202; At least one light-shielding plate 901 is provided on one side of the guide bracket 105, and the light-shielding plate 901 is adapted to the photoelectric sensor group 9.

[0027] Specifically, the light-shielding plate 901 moves with the guide bracket 105. When the guide bracket 105 is fed to the test completion position, the light-shielding plate 901 blocks the photoelectric sensor group 9 at the feed limit position. The sensor triggers a signal, thereby stopping the feed. After the test is completed, the lead screw body 206 rotates in the opposite direction, driving the guide bracket 105 to return to its axial position. The light-shielding plate 901 returns to its position with the guide bracket 105. When the guide bracket 105 returns to the detection position, the light-shielding plate 901 blocks the photoelectric sensor at the detection positioning position. The sensor triggers a signal, stopping the axial displacement of the guide bracket 105. At this time, the internal eddy current probe 6 is precisely aligned with the working cone area 501 and the sizing belt 502 for detection. In this embodiment, the photoelectric sensor group 9 is set to cooperate with the light shield 901 to accurately limit the axial feed and reset limit positions of the guide bracket 105, so as to avoid excessive feed causing the test mandrel 101 to harden the mold, or excessive reset causing the inner eddy current probe 6 to deviate from the detection position, thereby achieving safe protection for equipment operation and improving operating accuracy. Furthermore, by triggering a photoelectric sensor signal, the test core 101 is automatically stopped at the testing station after being reset, avoiding errors caused by manual positioning and improving the level of automation in the testing process. Furthermore, the photoelectric sensor group 9 provides real-time feedback on the displacement status of the guide bracket 105, enabling status monitoring and data traceability of the entire detection process, which facilitates equipment debugging and fault diagnosis. Preferably, the light-shielding plate 901 is a thin metal light-shielding plate, which is fixed to one side of the guide bracket 105 by bolts and is precisely aligned with the photoelectric sensor group 9. It can move axially synchronously with the guide bracket 105. When the guide bracket 105 moves to the corresponding work position, the light-shielding plate 901 just blocks the corresponding photoelectric sensor and triggers the positioning signal.

[0028] Based on the above embodiments, the clamping fixture 3 includes a three-jaw chuck 301, one end of which is rotatably connected to a fixed support 302, and the bottom of the fixed support 302 is fixedly connected to a base plate 303, which is bolted to the bottom base 7. Both the three-jaw chuck 301 and the fixed support 302 have through holes for accommodating the test mandrel 101. One end of the three-jaw chuck 301 is fixedly connected to a gear 304, and the bottom of the gear 304 is meshed with a gear 305, which is driven to rotate by a rotary drive unit.

[0029] Specifically, the staff inserts the drawing die body 5 into the three-jaw chuck 301, and uses the three-jaw chuck 301 to center and clamp the die, ensuring that the die and the test mandrel 101 are coaxial. Then, the test mandrel 101 first passes through the inner hole of the drawing die body 5, and then passes through the inner through holes of the three-jaw chuck 301 and the fixed support 302 to complete the storage. During this process, the rotary drive unit drives the second gear 305 to rotate, and the second gear 305 meshes with the drive gear 1 304 to rotate, thereby driving the three-jaw chuck 301 and the drawing die body 5 to rotate at a uniform speed. In this embodiment, a three-jaw chuck 301 is set as a clamping component to achieve rapid centering and clamping of the drawing die body 5, ensuring that the inner hole of the die coincides with the axis of the test mandrel 101 and the internal eddy current probe 6, avoiding die clamping eccentricity, further ensuring the uniformity and accuracy of testing and coating detection, and is applicable to clamping operations of drawing die bodies 5 of different specifications, with good versatility. Furthermore, the power of the rotary drive unit is transmitted to the three-jaw chuck 301 through the meshing transmission of gear 1 304 and gear 2 305, thereby avoiding interference with the inner hole and the insertion test mandrel 101 caused by the coaxial driving of the drive mechanism to the three-jaw chuck 301. Preferably, the base plate 303 is a steel plate, which is fixed to the upper surface of the bottom base 7 by bolts and serves as the installation reference for the three-jaw chuck 301. The fixed support 302 is vertically fixed to the top surface of the base plate 303 and is equipped with an angular contact ball bearing. One end of the three-jaw chuck 301 is rotatably connected to the fixed support 302 through the bearing. Preferably, the three-jaw chuck 301 is an industrial-grade self-centering three-jaw chuck with a self-centering accuracy of ≤0.005mm. The jaws are made of hardened alloy steel, which is wear-resistant and has high clamping force, and is suitable for drawing die bodies 5 with different outer diameter specifications.

[0030] Based on the above embodiments, the rotary drive unit includes an extension shaft 208, which is connected to one end of the lead screw body 206 near the clamping fixture 3, and one end of the extension shaft 208 is connected to the gear 2 305.

[0031] Specifically, when the lead screw body 206 rotates, two sets of synchronous movements are performed simultaneously: the rotation of the lead screw body 206 drives the nut seat 205, support seat 204 and guide bracket 105 to make axial linear feed along the guide rail 202, and the rotation of the lead screw body 206 drives the end extension shaft 208 to rotate synchronously. The extension shaft 208 drives the gear 2 305 and gear 1 304 to mesh and rotate, thereby driving the three-jaw chuck 301 and the drawing die body 5 to rotate at a uniform speed, so as to realize that the axial feed of the test mandrel 101 and the rotation of the die are synchronized, forming a spiral compound friction on the inner hole of the die, further ensuring uniform testing throughout the entire area; In this embodiment, the lead screw body 206 directly drives the extension shaft 208 to rotate, so that the axial feeding of the test mandrel 101 is synchronized with the rotation of the three-jaw chuck 301 and the drawing die body 5, avoiding errors caused by asynchronous motion, ensuring consistent motion sequence during the test, and further improving the uniformity of coating stress and the consistency of detection. Furthermore, by setting the lead screw body 206, linear feed and rotary drive can be completed simultaneously, eliminating the need for an independent rotary motor and matching transmission structure, reducing the number of parts and transmission length, thereby reducing equipment failure rate and maintenance costs, and improving reliability; Furthermore, the rotational speed of the lead screw body 206 and the rotational speed of the drawing die body 5 form a fixed transmission ratio, and the feed speed and circumferential linear speed are matched with each other, so as to stably realize the spiral full-range test within a limited test stroke in this application, ensuring comprehensive detection. Furthermore, by setting the extension shaft 208 to coaxially connect the lead screw body 206 and the gear 305, no additional installation space is required, the overall size of the equipment is smaller, the layout is more reasonable, and the overall structure of the machine is more streamlined. Preferably, the extension shaft 208 and the lead screw body 206 are coaxially connected by a rigid coupling with a coaxiality error of ≤0.005mm, to avoid torsion and eccentricity and ensure rotational transmission accuracy; Preferably, a support bearing sleeve 209 is provided on the outer side of the extension shaft 208 and fixed on the bottom base 7 to reduce cantilever deflection and ensure smooth rotation.

[0032] Based on the above embodiments, the rotary drive unit includes a motor assembly 8, which is fixed to the bottom of the bottom base 7. The output end of the motor assembly 8 is provided with a pulley 801, and a pulley 802 is connected to one side of the pulley 801. The pulley 802 is connected to the lead screw body 206.

[0033] In this embodiment, the motor assembly 8 is set as the power source, and the lead screw body 206 is driven to rotate through the pulley transmission to realize the synchronous movement of the axial feed of the test mandrel 101 and the circumferential rotation of the drawing die body 5. The motor speed can be adjusted independently, which is suitable for testing requirements of molds of different specifications and coating types, thus improving versatility. Furthermore, a pulley drive is installed, which has a simple structure and high transmission efficiency. The motor assembly 8 is fixed below the bottom base 7, which does not occupy the space of the top detection area, making the top layout of the equipment more concise. Preferably, pulley 801 and pulley 802 are synchronous pulleys, which work with a synchronous belt to transmit power, avoid slippage and ensure transmission accuracy; and dust covers are provided on the outside of pulley 801 and pulley 802 to protect the transmission components and extend their service life. Preferably, the speed of transmission is adjusted by adjusting the gear ratio between gear 1 304 and gear 2 305, and the rotational drive speed of the three-jaw chuck 301 can be adjusted according to the test requirements.

[0034] Based on the above embodiments, the support base 204 and the nut base 205 are rotatably connected and an automatic locking mechanism is provided between them.

[0035] In this embodiment, an automatic locking mechanism is set to control the fixed and unlocked states of the support base 204 and the nut base 205, thereby flexibly switching between linkage mode and independent mode. When testing, it automatically locks, realizing synchronous linkage between the axial feeding of the test mandrel 101 and the rotation of the three-jaw chuck 301; when it is necessary to position the inner eddy current probe 6 for coating detection, it unlocks and cancels the linkage, thereby independently controlling the rotation of the mold to achieve full circumference detection, avoiding the problems of the original linkage being inseparable and the single application scenario, and providing good flexibility. Furthermore, during coating inspection, the automatic locking mechanism unlocks, keeping the test mandrel 101 stationary while the mold rotates independently. This avoids interference from the slight displacement of the mandrel on the detection of the internal eddy current probe 6, ensuring that the probe is always aligned with the working cone area 501 and the sizing zone 502, improving the accuracy and stability of coating quality inspection, and avoiding detection errors caused by the movement of the mandrel in the linkage state. Furthermore, setting a single drive source and an automatic locking mechanism simplifies the control logic and reduces the risk of failure. It avoids setting up independent motors and feed motors for separate control, which can lead to speed mismatch and asynchronous start-stop. In addition, long-term operation of dual motors will accumulate errors, resulting in uneven friction testing. This causes the friction trajectory between the test mandrel 101 and the inner hole of the mold to deviate, reducing the detection accuracy and making it impossible to accurately test the coating adhesion and wear resistance. Furthermore, there is no need to set up an independent motor and corresponding transmission components to occupy additional installation space, thereby further reducing the size of the equipment, avoiding more failure points, and eliminating the need for an independent motor to provide redundant power, thus avoiding the structural redundancy and cost waste caused by an independent motor. Preferably, a deep groove ball bearing is installed in the socket hole at the center of the support seat 204, and the nut seat 205 passes through the inner ring of the bearing to realize the rotational connection between the support seat 204 and the nut seat 205. When the automatic locking mechanism is in the unlocked state, the nut seat 205 rotates synchronously with the lead screw body 206, while the support seat 204 remains stationary. Preferably, the automatic locking mechanism adopts an electromagnetic locking system, including an electromagnetic coil 401, a locking pin 402, and a locking hole 403. The electromagnetic coil 401 is fixed to the bottom of the support base 204 by an L-shaped bracket 404 and is electrically connected to the equipment control system, which can receive control signals to realize power on and power off. The locking pin 402 is installed inside the electromagnetic coil 401 and can make axial extension and retraction movements under the action of electromagnetic force. The locking holes 403 are evenly opened around the outer side wall of the nut seat 205. When the locking pin 402 extends, it is inserted into the locking hole 403 to realize the relative fixation of the support base 204 and the nut seat 205. When the locking pin 402 retracts, it disengages from the locking hole 403 to unlock the two, and the nut seat 205 can rotate relative to the support base 204. Preferably, the locking pin 402 and the locking hole 403 are fitted with a tapered surface, which facilitates the quick insertion and positioning of the locking pin 402. Multiple locking holes 403 are evenly arranged along the circumference of the nut seat, which can realize multi-angle locking and improve the reliability of locking.

[0036] Based on the above embodiment, the tapered variable diameter head 102 is fixedly connected to the end of the test mandrel 101.

[0037] like Figure 3As shown, specifically, when the automatic locking mechanism is in the locked state, the nut seat 205 drives the support seat 204 and the guide bracket 105 to feed axially along the guide rail 202. At the same time, the three-jaw chuck 301 drives the drawing die body 5 to rotate at a constant speed, so that the head of the test mandrel 101 first extends into the inner hole of the die and contacts the sizing belt 502. Under the synchronous action of axial feeding and die rotation, the coating of the sizing belt 502 is tested. Until the tapered reducing head 102 at the end of the test mandrel 101 comes into contact with the working cone area 501, the pressure sensor 4 detects the pressure change and reaches the preset threshold, and sends a signal to the control module. The control module controls the automatic locking mechanism to disconnect the connection between the support seat 204 and the nut seat 205. At this time, the screw body 206 continues to rotate, only driving the three-jaw chuck 301 and the drawing die body 5 to rotate, so that the working cone Zone 501 undergoes a circumferential rotation test relative to the tapered reducing head 102. After the test, the control module receives a preset test completion signal and re-controls the automatic locking mechanism to re-fix the support 204 and nut seat 205. At this time, the motor assembly 8 starts in reverse, driving the lead screw body 206 to rotate in reverse, driving the guide bracket 105 and test mandrel 101 to axially reset. When the guide bracket 105 resets to the detection station, the light shield 901 blocks the photoelectric sensor at the detection positioning station, and the sensor sends a signal to the control module. The control module controls the automatic locking mechanism to disconnect the connection between the support 204 and nut seat 205. The lead screw body 206 continues to rotate, only driving the drawing die body 5 to rotate at a constant speed, so that the inner eddy current probe 6 is aligned with the working cone zone 501 and the sizing belt 502, completing the eddy current detection of the coating around the entire circumference of the die inner hole. In this embodiment, a tapered variable diameter head 102 is fixedly connected to the end of the test mandrel 101 to achieve phased testing of the sizing band 502 and the working cone area 501. First, the test mandrel 101 completes the testing of the coating of the sizing band 502, and then the tapered variable diameter head 102 tests the working cone area 501. This phased targeted testing conforms to the axial distribution of the working cone area 501 and the sizing band 502 in the mold hole, ensuring that both core coating areas can be covered and tested during testing. Furthermore, the locking and unlocking signals of the automatic locking mechanism are linked with the photoelectric sensor group 9. When the light-shielding sheet 901 triggers the corresponding position sensor, the system automatically controls the electromagnetic unlocking to achieve automated control without manual intervention. Preferably, the test mandrel 101 has a stepped shaft machined at its end, and the tapered variable diameter head 102 has a mounting hole at its center that matches the stepped shaft. The two are fitted with an interference fit to ensure connection rigidity and avoid relative rotation and axial movement.

[0038] like Figure 8As shown, in order to further simulate the axial force generated simultaneously by the working cone area 501 and the sizing belt 502 during the copper tube diameter reduction forming process, and to avoid the situation in the above embodiment where only the circumferential rotation detection of the working cone area 501 can be performed, this embodiment also provides a technical solution for the detection integration part 1: the tapered variable diameter head 102 is slidably fitted on the outside of the test mandrel 101, the end of the test mandrel 101 is fixedly connected to a retaining ring 108, and a spring member 109 is sleeved on the outside of the test mandrel 101. The two ends of the spring member 109 are respectively connected to the retaining ring 108 and the tapered variable diameter head 102. The test mandrel 101 has keyways 110 on both sides, and a straight key is axially arranged inside the tapered variable diameter head 102, which slides along the keyway 110.

[0039] Specifically, by axially feeding the test mandrel 101 and rotating the mold, the tapered reducing head 102 directly contacts the working cone area 501. As the feed goes deeper, it compresses the spring 109, generating an increasing axial thrust. At the same time, the test mandrel 101 is inserted into the sizing belt 502, realizing a dual-area synchronous force test, which truly simulates the process of gradual force on the copper tube as it shrinks in diameter. When the test is completed and the tube is reset to the inspection station, the automatic locking mechanism unlocks, and the mold rotates independently, allowing the eddy current probe 6 to perform full-circumference coating inspection on the working cone area 501 and the sizing belt 502. In this embodiment, the spring 109 achieves an increasing axial pushing force, forming a continuously increasing test pressure on the working cone area 501. This further simulates the load gradually experienced by the copper tube along the working cone area 501 during the diameter reduction forming process. Compared with a fixed cone head, this method further tests the adhesion and wear resistance of the coating under progressive deformation and continuous pressure conditions, solving the problem that traditional testing methods cannot simulate the real diameter reduction mechanical state. Furthermore, through the sliding guide cooperation between the straight keyway 110 and the straight key, and the elastic support of the spring component 109, the tapered reducing head 102 and the test mandrel 101 can simultaneously adhere to and act on the corresponding detection area. During the rotational friction process, the coating of the working cone area 501 and the sizing belt 502 is tested simultaneously, avoiding single circumferential rotational detection of the working cone area 501 in the core diameter reduction forming area, thus improving the comprehensiveness of the detection. Furthermore, a sliding fit between the straight key and the straight keyway 110 is set to ensure that the tapered variable diameter head 102 slides along the mandrel axis and avoids relative rotation in its circumference, ensuring uniform force and stable trajectory during rotation testing, avoiding detection errors caused by sliding misalignment, and a spring mechanical structure is set to achieve incremental thrust without the need to add independent drive components, making the structural design simple and reliable. Preferably, a tapered variable diameter head 102 is fitted onto the outside of the test mandrel 101 with a clearance fit and can slide axially. A retaining ring 108 is provided at the end of the mandrel to limit the maximum displacement distance. Preferably, the spring 109 is a rectangular cross-section compression spring with high elastic linearity. The axial force increases steadily with the amount of compression, and the elastic force range matches the actual force of the copper tube with reduced diameter. In addition, the end face of the spring is ground flat, so as to stably fit with the retaining ring 108 and the tapered reducing head 102.

[0040] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection, the internal communication between two components, or the interaction between two components. Those skilled in the art can understand the meaning of the above terms in this application according to the specific circumstances.

[0041] The above provides a detailed description of a surface coating quality inspection system for copper tube drawing dies provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the technical solutions and core ideas of this application. 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 of the technical features. These 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 surface coating quality inspection system specifically for copper tube drawing dies, characterized in that, It includes a bottom base, a drawing die body, an integrated detection unit, and a clamping fixture; The clamping fixture is used to clamp the drawing die body; The bottom of the clamping fixture is provided with a rotary drive unit; An axial displacement module is provided at the bottom of the detection integration unit; The detection integration unit includes a test core rod; The diameter of the test mandrel is adapted to the sizing band of the drawing die body; A tapered variable diameter head is sleeved on the outside of the test mandrel, and the tapered variable diameter head is adapted to the working cone area of ​​the drawing die body; An internal eddy current probe is installed at the head end of the test mandrel.

2. The surface coating quality inspection system for copper tube drawing dies according to claim 1, characterized in that, One end of the test mandrel is fixedly connected to a fixed base, one end of the fixed base is provided with a fixed plate, and one side of the fixed plate is provided with a guide bracket, which is driven to move by an axial displacement module. A number of guide pins are fixedly connected to one side of the fixed plate. The guide pins pass through and are slidably fitted with guide sleeves. The guide sleeves pass through the vertical plate of the guide bracket and are fixedly connected to it. A pressure sensor and a spring assembly are installed between the fixed plate and the vertical plate of the guide bracket.

3. The surface coating quality inspection system for copper tube drawing dies according to claim 2, characterized in that, The axial displacement module includes a slider assembly, which is disposed at the bottom of the guide bracket; The bottom of the slider assembly is slidably fitted with a guide rail, and a guide rail pad is provided at the bottom of the guide rail, and the guide rail pad is fixed to the upper surface of the bottom base. The bottom of the guide bracket is provided with a support base, the center of the support base is provided with a sleeve hole, a nut seat is provided in the sleeve hole, and a lead screw body is provided inside the nut seat. The lead screw body is provided with bearing seats at both ends, and the bearing seats are bolted to the bottom base.

4. The surface coating quality inspection system for copper tube drawing dies according to claim 3, characterized in that, A photoelectric sensor group is provided on the upper surface of the bottom base, and the photoelectric sensor group is arranged along one side of the guide rail; At least one light-shielding plate is provided on one side of the guide bracket, and the light-shielding plate is adapted to the photoelectric sensor group.

5. A surface coating quality inspection system for copper tube drawing dies according to claim 3, characterized in that, The clamping fixture includes a three-jaw chuck, one end of which is rotatably connected to a fixed support, and a base plate is fixedly connected to the bottom of the fixed support, the base plate being bolted to the bottom base; Both the three-jaw chuck and the fixed support have through holes at their centers to accommodate the test mandrel. One end of the three-jaw chuck is fixedly connected to a gear 1, and the bottom of the gear 1 is meshed with a gear 2, which is driven to rotate by a rotary drive unit.

6. A surface coating quality inspection system for copper tube drawing dies according to claim 5, characterized in that, The rotary drive unit includes an extension shaft, which is connected to one end of the lead screw body near the clamping fixture, and one end of the extension shaft is connected to a gear.

7. A surface coating quality inspection system for copper tube drawing dies according to claim 3 or 6, characterized in that, The rotary drive unit includes a motor assembly, which is fixed to the bottom of the base. The output end of the motor assembly is provided with a pulley one, and a pulley two is connected to one side of the pulley one. The pulley two is connected to the lead screw body.

8. A surface coating quality inspection system for copper tube drawing dies according to claim 6, characterized in that, The support base and the nut base are rotatably connected and an automatic locking mechanism is provided between them; The automatic locking mechanism includes an electromagnetic coil, a locking pin, and a lock hole; The electromagnetic coil is fixed to the bottom of the support base by an L-shaped bracket. The locking pin is installed inside the electromagnetic coil and moves axially under the action of electromagnetic force. The locking holes are evenly opened around the outer side wall of the nut seat. When the locking pin extends, it is inserted into the locking hole.

9. A surface coating quality inspection system for copper tube drawing dies according to claim 8, characterized in that, The tapered reducing head is fixedly connected to the end of the test mandrel.

10. A surface coating quality inspection system for copper tube drawing dies according to claim 8, characterized in that, The tapered variable diameter head is slidably fitted on the outside of the test mandrel. A retaining ring is fixedly connected to the end of the test mandrel. A spring is sleeved on the outside of the test mandrel. The two ends of the spring are respectively connected to the retaining ring and the tapered variable diameter head. The test mandrel has straight keyways on both sides, and the tapered variable diameter head has a straight key axially arranged inside, which slides along the straight keyway.

Images