A device for detecting the air tightness of a screw sleeve

Abstract

The application belongs to the field of fastener quality inspection, and particularly relates to a sleeve air tightness detection device, which comprises a rack, a linear reciprocating mechanism and an air tightness detection mechanism; wherein the rack is provided with a positioning base for placing one end of a workpiece to be detected with a plug; the execution end of the linear reciprocating mechanism is provided with a gas supply pressure head for plugging the end of the workpiece to be detected away from the plug; the air tightness detection mechanism comprises a controller, a pressure controller connected to a corresponding pipeline, a pressure switch and an electromagnetic valve, and the pressure controller, the pressure switch and the electromagnetic valve are in communication connection with the controller. The sleeve air tightness detection device can replace the traditional manual detection mode, significantly improve the detection quantity per unit time, adopt a standardized detection process and a high-precision sensor, avoid misjudgment or missed detection caused by inconsistent human judgment, reliably detect the sleeve with air leakage defects, and prevent defective products from flowing into subsequent processes or causing faults in field use.

Description

Technical Field

[0001] This application belongs to the field of fastener quality inspection, specifically relating to a device for testing the airtightness of threaded sleeves. Background Technology

[0002] A plug is installed at one end of the threaded sleeve used in wind turbine installations, and resin glue is injected into the sleeve to fill the tiny gaps between the threads, making the connection between the bolt and the sleeve tighter and more secure, and achieving a sealing and corrosion-proof effect. After the plug is installed at one end of the threaded sleeve, an airtightness test is required to prevent glue leakage during use.

[0003] Currently, most inspections are done manually, which is inefficient and prone to errors, and does not meet current production needs. Summary of the Invention

[0004] The technical problem to be solved by this application is to provide a screw sleeve airtightness testing device that can standardize the testing, reduce the error rate, and improve the testing efficiency.

[0005] This application provides a device for testing the airtightness of threaded sleeves, comprising:

[0006] The frame is equipped with a positioning base, which is used to place the end of the workpiece to be tested with the plug.

[0007] A linear reciprocating mechanism, wherein the actuator end of the linear reciprocating mechanism is provided with an air supply head for sealing the end of the workpiece to be tested away from the plug;

[0008] An airtightness testing mechanism includes a controller, a pressure controller, a pressure switch, and a solenoid valve connected to corresponding pipelines. The pressure controller, pressure switch, and solenoid valve are communicatively connected to the controller, and the solenoid valve is connected to an external air supply pipeline or an exhaust pipeline connected to a vacuum pump.

[0009] Optionally, the air supply head includes a sleeve for connecting the actuator end of the linear reciprocating mechanism and a connector connected to the sleeve. The connector has a vent hole, and the two ends of the vent hole are used to connect the pipeline of the airtightness testing mechanism and the inner hole of the workpiece to be tested, respectively. The connector has an annular stepped structure that is inserted into the inner hole of the workpiece to be tested, and the annular stepped structure is fitted with a sealing ring for sealing between the connector and the workpiece to be tested.

[0010] Optionally, the portion of the connector used for insertion into the inner hole of the workpiece to be tested is conical in shape.

[0011] Optionally, the linear reciprocating mechanism includes a support frame and a linear actuator mounted on the support frame, with the air supply head connected to the actuator end of the linear actuator.

[0012] Optionally, the linear actuator is an electric cylinder or an electric push rod.

[0013] Optionally, the bracket is disposed on the top of the frame, and the execution direction of the linear actuator is perpendicular to the vertical direction of the positioning base.

[0014] Optionally, the positioning base is a magnetic field generator that stabilizes the workpiece under test through magnetic force.

[0015] Optionally, the positioning base has a positioning groove that engages with the end of the workpiece to be measured.

[0016] Optionally, the magnetic field generator is a permanent magnet.

[0017] Optionally, the threaded sleeve airtightness testing device further includes a positioning frame assembly disposed on one side of the positioning base. The positioning frame assembly includes a fixed base and a limiting member disposed on the fixed base. The limiting member has a symmetrical curved surface that contacts the side wall of the workpiece to be tested.

[0018] Optionally, the fixed base is provided with limit plates on both sides, and the limit member is located between the limit plates on both sides and is clearance-fitted. The limit member has a waist-shaped hole for connecting to the fixed base by fastening bolts and adjusting the extension amount according to the specifications of the workpiece to be tested.

[0019] The beneficial effects of this application are as follows: The end of the threaded sleeve to be tested, with the plug, is placed on the positioning base and kept stable. A linear reciprocating mechanism is activated, causing the air supply head to move to the other end of the threaded sleeve and make tight contact, achieving a seal at both ends. The controller, according to a preset program, controls the injection of gas at a certain pressure or the extraction of a vacuum into the threaded sleeve via a solenoid valve. The pressure or vacuum state is maintained for a set time. A pressure controller and pressure switch monitor whether the internal pressure drops. If the pressure remains stable, the seal is good; if the pressure drops, there may be a leak. The display screen or indicator light shows the test results for easy identification by the operator. After the test is completed, the solenoid valve releases the gas, the air supply head returns to its original position, and the operator removes the workpiece. This method can replace traditional manual inspection methods, significantly increasing the number of tests per unit time. By adopting a standardized inspection process and high-precision sensors, it avoids misjudgments or missed detections caused by inconsistent human judgment, reliably detecting threaded sleeves with leakage defects, and preventing defective products from flowing into subsequent processes or causing malfunctions during on-site use. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural schematic diagram of the screw sleeve airtightness testing device provided in the embodiments of this application;

[0021] Figure 2 This is a rear view of the threaded sleeve airtightness testing device provided in an embodiment of this application;

[0022] Figure 3 A three-dimensional structural schematic diagram of the air supply head provided in the embodiments of this application;

[0023] Figure 4 A longitudinal cross-sectional structural diagram of the air supply head provided in the embodiments of this application;

[0024] Figure 5 This is a three-dimensional structural diagram of the positioning frame assembly provided in the embodiments of this application;

[0025] Figure 6 This is an exploded structural diagram of the positioning frame assembly provided in an embodiment of this application.

[0026] In the diagram: 100, frame; 110, positioning base; 210, bracket; 220, linear actuator; 300, air supply head; 310, sleeve; 320, connector; 321, vent hole; 322, annular stepped structure; 330, sealing ring; 410, controller; 420, pressure controller; 430, pressure switch; 440, solenoid valve; 500, positioning frame assembly; 510, fixed seat; 511, limit plate; 520, limit component; 521, symmetrical curved surface; 522, waist-shaped hole. Detailed Implementation

[0027] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0028] As shown in Figures 1-6, the screw sleeve airtightness testing device provided in this application includes: a frame 100, a linear reciprocating mechanism, and an airtightness testing mechanism; wherein, the frame 100 is provided with a positioning base 110, which is used to place the end of the workpiece to be tested with a plug; the execution end of the linear reciprocating mechanism is provided with an air supply head 300, which is used to seal the end of the workpiece to be tested away from the plug; the airtightness testing mechanism includes a controller 410, a pressure controller 420, a pressure switch 430, and a solenoid valve 440 connected in corresponding pipelines, the pressure controller 420, the pressure switch 430, and the solenoid valve 440 being communicatively connected to the controller 410, and the solenoid valve 440 being connected to an external air supply pipeline or to an exhaust pipeline connected to a vacuum pump.

[0029] Compared with the prior art, the threaded sleeve airtightness testing device provided in this application places the end of the threaded sleeve to be tested with the plug on the positioning base 110 and keeps it stable. The linear reciprocating mechanism is activated to move the air supply head 300 to the other end of the threaded sleeve and make tight contact, thereby achieving a seal at both ends of the threaded sleeve. The controller 410 controls the injection of gas at a certain pressure or the extraction of vacuum into the threaded sleeve through the solenoid valve 440 according to the preset program. The pressure or vacuum state is maintained for a set time. The pressure controller 420 and the pressure switch 430 monitor whether the internal pressure drops. If the pressure remains stable, it indicates that the seal is good; if the pressure drops, there may be an air leakage. The display screen or indicator light shows the test results for easy identification by the operator. After the test is completed, the solenoid valve 440 exhausts the gas, the air supply head 300 returns to its original position, and the operator removes the workpiece. This allows it to replace traditional manual inspection methods, significantly increasing the number of inspections per unit time. By adopting standardized inspection procedures and high-precision sensors, it avoids misjudgments or missed inspections caused by inconsistent human judgments, reliably detecting threaded sleeves with air leakage defects, and preventing defective products from flowing into subsequent processes or causing malfunctions during on-site use.

[0030] It should be noted that the pressure controller 420 is directly connected to the gas pipeline to monitor the internal pressure level of the system and adjust the working state of the vacuum pump or gas supply equipment according to the set value. It can automatically adjust the pressure within the system to ensure that it is maintained within a specific range. The pressure switch 430 is also installed in the gas pipeline. It can be mechanical or electronic and is mainly used to trigger an action when the pressure within the system reaches the preset high or low limit value. The solenoid valve 440 is installed at the location where the gas flow direction needs to be controlled, such as the pipeline between the vacuum pump and the object under test or the gas supply pipeline directly connected to the object under test. It opens or closes the valve by receiving electrical signals from the control system, thereby controlling the entry or exit of gas to maintain the required test conditions. The control system (such as PLC, microcontroller, etc.) is connected to the pressure controller 420, pressure switch 430, and solenoid valve 440. It is responsible for receiving data from the sensors and sending control commands to the solenoid valve 440 according to the program logic.

[0031] In one possible implementation, such as Figure 3As shown, the air supply head 300 includes a sleeve 310 for connecting to the actuator of the linear reciprocating mechanism and a connector 320 connected to the sleeve 310. The connector 320 has a vent hole 321, the two ends of which are used to connect to the pipeline of the airtightness testing mechanism and the inner hole of the workpiece to be tested, respectively. The connector 320 has an annular stepped structure 322 inserted into the inner hole of the workpiece to be tested. A sealing ring 330 is fitted onto the annular stepped structure 322 for sealing between the connector 320 and the workpiece to be tested. Specifically, the sleeve 310 can be fixedly connected to the actuator of the linear reciprocating mechanism via a flange, thread, bolt, or quick-connect connector 320 to ensure that the air supply head 300 can move synchronously with the linear reciprocating mechanism to achieve sealing of the workpiece. The connection between the sleeve 310 and the connector 320 can be a threaded connection, a snap-fit ​​connection, welding, or a flange connection. The vent hole 321 is used for gas injection or vacuuming and is a key channel for pressure testing. The outer diameter of the annular stepped structure 322 is slightly smaller than the inner diameter of the threaded sleeve. After insertion, it provides guidance and positioning. A groove is provided at the step for installing the sealing ring 330, achieving a tight seal between the sealing ring 330 and the workpiece. The sealing ring 330 is made of elastic materials such as rubber or silicone to prevent gas leakage between the connector 320 and the workpiece, thus improving detection accuracy. Furthermore, the connector 320 is replaceable or adjustable, facilitating adaptation to threaded sleeves of different sizes and enhancing the versatility and flexibility of the equipment.

[0032] In one possible implementation, such as Figure 4 As shown, the portion of connector 320 used for insertion into the inner hole of the workpiece to be tested is conical. Specifically, the outlet of the vent 321 is located at the center of connector 320. The conical connector 320 mates with the inner hole of the workpiece, serving a guiding and positioning function.

[0033] In one possible implementation, such as Figure 2 As shown, the linear reciprocating mechanism includes a bracket 210, a linear actuator 220 mounted on the bracket 210, and an air supply head 300 connected to the actuating end of the linear actuator 220. Specifically, the bracket 210 can be fixed to the table of the frame 100 by welding, flange, and bolts. The linear actuator 220 is installed at a certain height, and the air supply head 300 is driven by the linear actuator 220 to reciprocate linearly, thereby achieving sealing and contact sealing of the end of the workpiece to be tested.

[0034] In one possible implementation, the linear actuator 220 is an electric cylinder or an electric actuator. Electric cylinders or actuators enable very precise position control, which is crucial for ensuring that the air supply head 300 accurately positions itself on the workpiece being tested. High-precision positioning avoids problems such as poor sealing or workpiece damage caused by mechanical errors. Furthermore, because the electric drive system is relatively simple and requires less maintenance, it reduces downtime due to repairs and maintenance.

[0035] In one possible implementation, the bracket 210 is positioned on top of the frame 100, and the linear actuator 220 operates in a vertical direction perpendicular to the positioning base 110. Specifically, when the test begins, the linear actuator 220 drives the air supply head 300 to move downwards vertically, precisely inserting it into the inner hole of the other end of the threaded sleeve to be tested. After insertion, the sealing ring 330 is compressed and tightly adheres to the inner wall of the threaded sleeve, forming a good sealing environment. Subsequently, air is injected or a vacuum is drawn into the threaded sleeve through the vent 321 for air tightness testing. After the test is completed, the linear actuator 220 drives the air supply head 300 to rise and reset, and the operator removes the workpiece. The vertical arrangement minimizes the horizontal space occupied by the equipment, which is beneficial for production line integration and space optimization. Furthermore, the vertical movement path facilitates high-precision guidance (which can be achieved with guide pillars, guide rails, etc.), avoiding skewing or jamming, ensuring that the air supply head 300 is accurately aligned with the inner hole of the threaded sleeve, improving the sealing success rate, and reducing false leak detections.

[0036] In one possible implementation, the positioning base 110 acts as a magnetic field generator, stabilizing the workpiece under test through magnetic force. Specifically, the positioning base 110 embeds an electromagnetic coil or permanent magnet array, forming a controllable or fixed magnetic field area. When the threaded sleeve to be tested (usually made of metal) is placed above this area, it is attracted and stabilized by the magnetic force. If an electromagnetic system is used, the magnetic force can be turned on and off by energizing it; if a permanent magnet system is used, the workpiece is attracted by the magnetic field generated by the permanent magnet. The magnetic field can be designed to be centralized or distributed at multiple points to accommodate threaded sleeves of different shapes and sizes. Utilizing magnetic attraction avoids the problems of offset and deformation caused by traditional mechanical clamps, enabling automatic centering and alignment of the workpiece with the positioning surface, ensuring complete alignment of the detection end face, eliminating grippers and friction, and preventing indentations or scratches on the workpiece surface. Threaded sleeves of different sizes can be adapted by adjusting the magnetic strength or replacing the magnetic attraction module, demonstrating strong adaptability and good versatility.

[0037] In one possible implementation, the positioning base 110 has a positioning groove that mates with the end of the workpiece to be tested. Specifically, a groove matching the shape of the end of the workpiece (such as a threaded sleeve) is machined on the surface of the positioning base 110. The groove can be designed as circular, conical, polygonal, or other irregular shapes to accommodate different types of threaded sleeve end shapes. When the workpiece is placed in the groove, its end is embedded within it; the groove serves to limit, guide, and center, preventing workpiece offset or tilting. It can be used alone or in combination with magnetic, pneumatic clamping, or other methods to enhance positioning stability. In use, the operator or robot vertically places the threaded sleeve with a plug into the groove of the positioning base 110, and the groove guides the workpiece to automatically center and stably position itself. Thus, the groove precisely mates with the end of the workpiece, achieving high repeatability and ensuring that the workpiece is in a consistent position during each test. This helps improve the success rate of the air supply head 300 docking and reduces sealing problems caused by misalignment. It also has the advantages of achieving stable positioning without relying on complex clamping mechanisms, simple structure, low manufacturing cost, and ease of maintenance and replacement.

[0038] In one possible implementation, such as Figure 5 As shown, the threaded sleeve airtightness testing device also includes a positioning frame assembly 500 disposed on one side of the positioning base 110. The positioning frame assembly 500 includes a fixed base 510 and a limiting member 520 disposed on the fixed base 510. The limiting member 520 has a symmetrical curved surface 521 that contacts the side wall of the workpiece to be tested. Specifically, the positioning frame assembly 500 is an auxiliary positioning structure. The positioning base 110 serves as the main support platform and is provided with a positioning groove or magnetic structure to achieve preliminary positioning of the workpiece. The fixed base 510 is installed on one side of the positioning base 110, providing support and fixation. The limiting member 520 is installed on the fixed base 510, and its surface is a symmetrical curved surface 521, used to conform to the outer side wall of the threaded sleeve to be tested. The curved surface shape is usually an arc or other curve adapted to the shape of the threaded sleeve. The symmetrical curved surface 521 limiting method can effectively restrict the degree of freedom of the threaded sleeve in the horizontal direction, ensuring that the workpiece axis and the air supply head 300 remain coaxial during each test, thereby improving the sealing success rate.

[0039] In one possible implementation, such as Figure 6As shown, the fixed base 510 has limit plates 511 on both sides, and a limiting member 520 is located between the two limit plates 511 with a clearance fit. The limiting member 520 has a slotted hole 522 for connecting to the fixed base 510 via a fastening bolt 530 and adjusting the extension amount according to the specifications of the workpiece to be measured. Specifically, the two limit plates 511 are fixed on the left and right sides of the fixed base 510, forming a clamping and guiding effect on the limiting member 520 to prevent it from shifting or shaking, and maintaining a certain clearance fit between them to facilitate the sliding or fine adjustment of the limiting member 520. The limiting member 520 is installed between the two limit plates 511, with a symmetrical curved surface 521 that fits against the outer wall of the threaded sleeve to be measured. It has a slotted hole 522 (elongated hole) on it, which is connected to the fixed base 510 via a fastening bolt 530 and moves along the hole direction to adjust the extension distance. In use, after loosening the fastening bolt 530 on the limiting member 520, the limiting member 520 can be slid back and forth within the range of the oblong hole 522. Adjust the position of the limiting member 520 according to the diameter of the threaded sleeve to be tested, so that it just contacts the outer wall of the threaded sleeve. After adjustment, tighten the fastening bolt 530 to complete the positioning of the limiting member 520. In this way, the extension of the limiting member 520 can be quickly adjusted according to threaded sleeves of different diameters, realizing the testing needs of multiple models of products with one device, improving the utilization rate of the equipment. The limiting member 520 can accurately fit the side wall of the threaded sleeve to prevent the workpiece from tilting or shifting. With the groove or magnetic structure of the positioning base 110, more comprehensive spatial positioning control can be achieved.

[0040] The controller 410 can be a Panasonic PLC module FP-XH C40T expansion module. The pressure switch 430 can be an Airtac DPSN1B-10020 pressure sensor, which is an intelligent high-precision pressure control device integrating pressure measurement, display, and control.

[0041] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of protection of this application is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of one or more embodiments of this application as described above, which are not provided in detail for the sake of brevity.

[0042] One or more embodiments in this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments in this application should be included within the protection scope of this application.

Claims

1. A device for detecting the airtightness of threaded sleeves, characterized in that, include: The frame (100) is provided with a positioning base (110), which is used to place the end of the workpiece to be tested with a plug. A linear reciprocating mechanism, wherein the actuator end of the linear reciprocating mechanism is provided with an air supply head (300) for sealing the end of the workpiece to be tested away from the plug; The airtightness testing mechanism includes a controller (410), a pressure controller (420), a pressure switch (430), and a solenoid valve (440) connected to the corresponding pipeline. The pressure controller (420), pressure switch (430), and solenoid valve (440) are communicatively connected to the controller (410). The solenoid valve (440) is connected to an external air supply pipeline or an exhaust pipeline connected to a vacuum pump.

2. The threaded sleeve airtightness testing device according to claim 1, characterized in that, The air supply head (300) includes a sleeve (310) for connecting the actuator end of the linear reciprocating mechanism and a connector (320) connected to the sleeve (310). The connector (320) has a vent hole (321). The two ends of the vent hole (321) are used to connect the pipeline of the air tightness testing mechanism and the inner hole of the workpiece to be tested, respectively. The connector (320) has an annular stepped structure (322) inserted into the inner hole of the workpiece to be tested. The annular stepped structure (322) is fitted with a sealing ring (330) for sealing between the connector (320) and the workpiece to be tested.

3. The threaded sleeve airtightness testing device according to claim 2, characterized in that, The connector (320) is cone-shaped and is used to insert into the inner hole of the workpiece to be tested.

4. The threaded sleeve airtightness testing device according to claim 1, characterized in that, The linear reciprocating mechanism includes a bracket (210) and a linear actuator (220) mounted on the bracket (210). The air supply head (300) is connected to the execution end of the linear actuator (220).

5. The threaded sleeve airtightness testing device according to claim 4, characterized in that, The linear actuator (220) is an electric cylinder or an electric push rod.

6. The threaded sleeve airtightness testing device according to claim 5, characterized in that, The bracket (210) is located on the top of the frame (100), and the linear actuator (220) operates in a vertical direction perpendicular to the positioning base (110).

7. The threaded sleeve airtightness testing device according to any one of claims 1-6, characterized in that, The positioning base (110) is a magnetic field generator that stabilizes the workpiece under test through magnetic force; Alternatively, the positioning base (110) has a positioning groove that engages with the end of the workpiece to be tested.

8. The threaded sleeve airtightness testing device according to claim 7, characterized in that, The magnetic field generator is a permanent magnet.

9. The threaded sleeve airtightness testing device according to any one of claims 1-6, characterized in that, It also includes a positioning frame assembly (500) disposed on one side of the positioning base (110). The positioning frame assembly (500) includes a fixed base (510) and a limiting member (520) disposed on the fixed base (510). The limiting member (520) has a symmetrical curved surface (521) that contacts the side wall of the workpiece to be tested.

10. The threaded sleeve airtightness testing device according to claim 9, characterized in that, Limiting plates (511) are provided on both sides of the fixed base (510). The limiting member (520) is located between the limiting plates (511) on both sides and is clearance-fitted. The limiting member (520) has a waist-shaped hole (522) for connecting to the fixed base (510) by fastening bolts (530) and adjusting the extension amount according to the specifications of the workpiece to be tested.

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