Pre-tightening force monitoring device
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TECH INFORMATION CENT SPIC HENAN ELECTRIC POWER CO LTD
- Filing Date
- 2025-06-19
- Publication Date
- 2026-05-26
AI Technical Summary
In the existing technology, the preload monitoring devices for fasteners from different batches have low accuracy in preload calibration in bolted connections, which cannot effectively solve assembly problems.
By employing a radio frequency strain coil and chip in the patent, a monitoring device is constructed, including a lower connector, an upper connector, and a test component. During monitoring, the lower and upper connectors are first connected using a fastener from an older batch to be tested, creating pressure within the required range. The fastener is then tightened, and the echo information from the radio frequency strain coil is acquired. A new batch of fasteners is then used, and gradually tightened. The test component deforms, and the radio frequency strain coil simultaneously deforms and emits echo information. This echo information is acquired in real time. When the current echo information is close to the previous one, the current number of tightening turns is identified as the number of tightening turns in the newly calibrated assembly tightening step, thus improving the accuracy of preload monitoring and preload calibration.
This improved the accuracy of preload monitoring and preload calibration, ensuring the reliability and consistency of assembly.
Smart Images
Figure CN224286204U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of preload testing technology, and in particular to a preload monitoring device. Background Technology
[0002] In the manufacturing process of electromechanical products, bolted connections are the most common and important assembly connection method. Besides the principle design, the assembly process design also determines product quality; the design of the assembly process determines whether the principle design can be reliably conveyed to the product.
[0003] In some critical mechanical products, such as automotive internal combustion engine systems, the tightening force of each bolt must meet design requirements to ensure reliable assembly. When there are few bolts or the requirements are not high, a torque wrench can be used to record the tightening torque of each bolt tightened. However, for products with high assembly requirements, especially when multiple bolts need to be tightened together, simply recording the tightening force of a single bolt cannot accurately determine the actual preload generated on the assembly. Furthermore, for fasteners from the same batch, it is usually necessary to accurately measure the actual preload after all fasteners are assembled once when they are first put into use, and record the number of turns of the screw thread used in the assembly to achieve a standardized and uniform assembly effect. However, when a fastener batch is changed, the differences in the material, processing level, and quality level of the new fasteners often result in fluctuations or differences in the stiffness coefficient within the standard allowable range. Therefore, the standardized number of turns of tightening recorded for the previous batch is no longer accurate.
[0004] Therefore, there is an urgent need for a preload monitoring device to solve the above-mentioned technical problems. Utility Model Content
[0005] The purpose of this invention is to provide a preload monitoring device, which aims to solve the problem of low accuracy of preload calibration for different batches of fasteners in the prior art. This preload monitoring device can improve the accuracy of preload monitoring and preload calibration.
[0006] To achieve this objective, the present invention adopts the following technical solution:
[0007] Preload monitoring device, including:
[0008] The lower connector has a flange protruding from its outer peripheral surface;
[0009] The upper connector is connected to the lower connector via a fastener to be tested, and the outer peripheral surface of the upper connector is provided with a locking step;
[0010] The test component is fitted and conforms to the outer periphery of the lower connector and the upper connector, and clamped between the support edge and the engagement step; wherein,
[0011] The outer peripheral surface of the lower connector is equipped with a radio frequency strain coil forming a radio frequency transmitting antenna and a chip containing identification information that is communicatively connected to the radio frequency strain coil. The radio frequency strain coil can synchronously generate deformation when the test component deforms and emit echo information.
[0012] In some possible implementations, the test component includes a lower test piece and an upper test piece, the lower test piece being fitted onto the lower connector, the upper test piece being fitted onto the upper connector, and the lower test piece and the upper test piece abutting against each other.
[0013] In some possible implementations, both the lower test piece and the upper test piece are configured as annular cylindrical structures.
[0014] In some possible implementations, both the lower test piece and the upper test piece are made of non-metallic material.
[0015] In some possible implementations, the lower connector has a first receiving groove, the upper connector has a second receiving groove, the first receiving groove and the second receiving groove together form a receiving space, and a counterweight is disposed in the receiving space.
[0016] In some possible implementations, the counterweight is detachably connected to the lower connector.
[0017] In some possible implementations, the counterweight is connected to the lower connector by fasteners, at least two of which are evenly distributed along the circumference of the lower connector.
[0018] In some possible implementations, the radio frequency strain coils are provided in multiple sets, and the multiple sets of radio frequency strain coils are evenly distributed along the circumference of the lower connector.
[0019] In some possible implementations, at least two fasteners to be tested are provided, and the at least two fasteners to be tested are evenly distributed along the circumference of the upper connector.
[0020] In some possible implementations, three fasteners to be tested are provided, and the three fasteners to be tested are evenly distributed along the circumference of the upper connector.
[0021] The beneficial effects of this utility model are as follows: The preload monitoring device provided by this utility model sets a test component between the lower connector and the upper connector, and installs an RF strain coil and a chip on the outer peripheral surface of the lower connector. During monitoring, the lower connector and the upper connector are first connected by the old batch of fasteners to be tested and form pressure within the required range. The fasteners to be tested are tightened and the echo information of the current RF strain coil is obtained. The new batch of fasteners to be tested is replaced and gradually tightened. The test component deforms, and the RF strain coil deforms synchronously and emits echo information. The echo information is obtained in real time. When the current echo information is close to the previous echo information, the current number of tightening turns is determined to be the number of tightening turns in the newly calibrated assembly tightening step, thereby improving the accuracy of preload monitoring and preload calibration. Attached Figure Description
[0022] Figure 1 This is a front view of the preload monitoring device provided in this embodiment of the utility model;
[0023] Figure 2 yes Figure 1 Sectional view at point AA;
[0024] Figure 3 This is an exploded view of the preload monitoring device provided in one embodiment of the present invention;
[0025] Figure 4 This is an exploded view of the preload monitoring device from another perspective provided in this embodiment of the utility model;
[0026] Figure 5 This is an assembly diagram of the lower test piece, lower connecting piece, and fastener provided in an embodiment of this utility model;
[0027] Figure 6 This is a schematic diagram showing the positional relationship between the lower test piece, the lower connecting piece, the upper test piece, and the upper connecting piece provided in this embodiment of the utility model;
[0028] Figure 7 This is a perspective view of the lower connector provided in an embodiment of this utility model.
[0029] In the picture:
[0030] 100 Lower connector; 110 Support flange; 120 First receiving groove; 200 Upper connector; 210 Engaging step; 220 Second receiving groove; 300 Fastener to be tested; 410 Lower test piece; 420 Upper test piece; 500 Radio frequency strain coil; 600 Chip; 700 Counterweight; 800 Locking component. Detailed Implementation
[0031] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.
[0032] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0033] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0034] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.
[0035] like Figures 1 to 7As shown, this embodiment provides a preload monitoring device, including a lower connector 100, an upper connector 200, and a test assembly. The lower connector 100 has a protruding flange 110 on its outer peripheral surface; the upper connector 200 is connected to the lower connector 100 via a fastener 300 to be tested, and the upper connector 200 has a protruding engaging step 210 on its outer peripheral surface; the test assembly is fitted and adhered to the outer peripheral sides of the lower connector 100 and the upper connector 200, and clamped between the flange 110 and the engaging step 210; wherein, a radio frequency strain coil 500 forming a radio frequency transmitting antenna and a chip 600 storing identification information, which is communicatively connected to the radio frequency strain coil 500, are mounted on the outer peripheral surface of the lower connector 100. The radio frequency strain coil 500 can synchronously deform when the test assembly deforms and emit echo information.
[0036] The preload monitoring device provided in this embodiment sets a test component between the lower connector 100 and the upper connector 200, and installs an RF strain coil 500 and a chip 600 on the outer peripheral surface of the lower connector 100. During monitoring, the lower connector 100 and the upper connector 200 are first connected through the old batch of fasteners to be tested 300 and form a pressure within the required range. The fasteners to be tested 300 are tightened and the echo information of the current RF strain coil 500 is obtained. The new batch of fasteners to be tested 300 is replaced and gradually tightened. The test component deforms, and the RF strain coil 500 deforms synchronously and emits echo information. The echo information is obtained in real time. When the current echo information is close to the previous echo information, the current number of tightening turns is identified as the number of tightening turns in the newly calibrated assembly tightening step, thereby improving the accuracy of preload monitoring and preload calibration.
[0037] It should be noted that the RF strain coil 500 forming the RF transmitting antenna in this embodiment can be understood as a passive transmitting device. It is twisted into a coil shape, and the induced current generated when a reader approaches it causes an alternating change in the electric field, transmitting a response electromagnetic signal determined by its twisted shape, such as a resonant frequency shift. This allows the reader to read the information from the RF antenna without requiring a power supply or circuitry for the RF strain coil 500 itself. The structure is simple, convenient to apply, and reliable. For example, in the RF tags used in automatic checkout in unmanned supermarkets, a chip 600 containing product information and an RF transmitting antenna connected to the chip 600 are placed on the tag and attached to the product. When the tag is brought close to the reader at checkout, the product information can be read for payment. In this embodiment, the RF strain coil 500 forming the RF transmitting antenna is in the shape of a thin metal sheet. Because the signal it emits is related to its shape, it can also function as a strain gauge. The RF strain coil 500 deforms synchronously with the deformation of the test component, and its resonant frequency shifts accordingly. This resonant frequency shift can be read by the reader.
[0038] Optionally, the test assembly includes a lower test piece 410 and an upper test piece 420. The lower test piece 410 is fitted onto the lower connector 100, and the upper test piece 420 is fitted onto the upper connector 200, with the lower test piece 410 and the upper test piece 420 abutting against each other. During monitoring, the lower test piece 410 is fitted onto the lower connector 100, and the radio frequency strain coil 500 is mounted on the outer peripheral surface of the lower connector 100. When the lower test piece 410 deforms, the radio frequency strain coil 500 deforms synchronously under the compressive force of the lower test piece 410. Since the tightening force of the fastener 300 under test is positively correlated with the deformation of the lower test piece 410, the tightening force can be monitored equally by the deformation of the lower test piece 410.
[0039] See Figures 2 to 6 Both the lower test piece 410 and the upper test piece 420 can be configured as annular cylindrical structures. Annular cylindrical structures are relatively simple and have low manufacturing costs. In other embodiments, the lower test piece 410 and the upper test piece 420 can be configured as other shapes, such as blocks, as needed. Preferably, both the lower test piece 410 and the upper test piece 420 are made of non-metallic materials. Non-metallic materials are prone to deformation under external force, allowing the radio frequency strain coil 500 to more sensitively capture deformation information and undergo deformation, thus improving monitoring accuracy.
[0040] Optionally, the lower connector 100 has a first receiving groove 120, and the upper connector 200 has a second receiving groove 220. The first receiving groove 120 and the second receiving groove 220 together form a receiving space, and a counterweight 700 is disposed within the receiving space. By disposing of the counterweight 700, the overall weight of the entire device can be increased to maintain balance and stability.
[0041] Preferably, the counterweight 700 is detachably connected to the lower connector 100. This arrangement improves the ease of assembly and disassembly. Exemplarily, the counterweight 700 is connected to the lower connector 100 via locking members 800. At least two locking members 800 are provided, and these at least two locking members 800 are evenly distributed along the circumference of the lower connector 100. In this embodiment, the locking members 800 may be threaded members, and three threaded members are provided, with the three threaded members evenly distributed along the circumference of the lower connector 100.
[0042] Optionally, multiple sets of radio frequency strain coils 500 are provided, and these multiple sets of radio frequency strain coils 500 are evenly distributed along the circumference of the lower connector 100. Multiple sets of radio frequency strain coils 500 can synchronously and comprehensively generate deformation at multiple locations under compressive force. Multiple sets of radio frequency strain coils 500 emit multiple echo signals, and the signal change range, such as the range of resonant frequency shift, can be determined based on these multiple echo signals. The average value of the resonant frequency shift can be obtained, improving the accuracy of monitoring. In this embodiment, three sets of radio frequency strain coils 500 are provided, and these three sets of radio frequency strain coils 500 are evenly distributed along the circumference of the lower connector 100. In other embodiments, the radio frequency strain coils 500 can be set to four or five sets, or other quantities, as needed.
[0043] Optionally, at least two fasteners 300 to be tested are provided, and the at least two fasteners 300 to be tested are evenly distributed along the circumference of the upper connector 200. In this embodiment, three fasteners 300 to be tested are provided, and the three fasteners 300 to be tested are evenly distributed along the circumference of the upper connector 200. Optionally, the fasteners 300 to be tested are hexagonal head bolts.
[0044] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.
Claims
1. A preload monitoring device, characterized in that, include: The lower connector (100) has a flange (110) protruding from its outer peripheral surface; The upper connector (200) is connected to the lower connector (100) via the fastener to be tested (300), and the outer peripheral surface of the upper connector (200) is provided with a locking step (210); The test component is fitted and conforms to the outer periphery of the lower connector (100) and the upper connector (200), and is clamped between the support edge (110) and the engagement step (210); wherein, The outer peripheral surface of the lower connector (100) is equipped with a radio frequency strain coil (500) forming a radio frequency transmitting antenna and a chip (600) containing identification information that is communicatively connected to the radio frequency strain coil (500). The radio frequency strain coil (500) can synchronously generate deformation when the test component deforms and emit echo information.
2. The preload monitoring device according to claim 1, characterized in that, The test component includes a lower test piece (410) and an upper test piece (420). The lower test piece (410) is fitted onto the lower connector (100), and the upper test piece (420) is fitted onto the upper connector (200). The lower test piece (410) and the upper test piece (420) abut against each other.
3. The preload monitoring device according to claim 2, characterized in that, Both the lower test piece (410) and the upper test piece (420) are configured as annular cylindrical structures.
4. The preload monitoring device according to claim 2, characterized in that, Both the lower test piece (410) and the upper test piece (420) are made of non-metallic material.
5. The preload monitoring device according to claim 1, characterized in that, The lower connector (100) has a first receiving groove (120), and the upper connector (200) has a second receiving groove (220). The first receiving groove (120) and the second receiving groove (220) together form a receiving space, and a counterweight (700) is provided in the receiving space.
6. The preload monitoring device according to claim 5, characterized in that, The counterweight (700) is detachably connected to the lower connector (100).
7. The preload monitoring device according to claim 6, characterized in that, The counterweight (700) is connected to the lower connector (100) by a locking member (800). At least two locking members (800) are provided, and the at least two locking members (800) are evenly distributed along the circumference of the lower connector (100).
8. The preload monitoring device according to claim 1, characterized in that, The radio frequency strain coil (500) is provided in multiple sets, and the multiple sets of radio frequency strain coil (500) are evenly distributed along the circumference of the lower connector (100).
9. The preload monitoring device according to claim 1, characterized in that, At least two fasteners (300) are provided, and the at least two fasteners (300) are evenly distributed along the circumference of the upper connector (200).
10. The preload monitoring device according to claim 9, characterized in that, Three fasteners (300) are provided, and the three fasteners (300) are evenly distributed along the circumference of the upper connector (200).