Detection module for detecting fastening device and fastening system

Abstract

The present application relates to a detection module for detecting a fastening device, comprising: a gasket (2) configured to be clamped by a fastening device (1) with a predetermined fastening force; a fiber optic cable (20) extending transversely in the gasket, the fiber optic cable having a fiber bragg grating assigned to the gasket, the fiber bragg grating being stress-deformable in response to a clamping force applied to the gasket by the fastening means; and a control unit connected to the fiber optic cable, the control unit being able to receive and process a feedback light signal generated by means of the fiber bragg grating, the clamping force and / or clamping force variation applied by the fastening device (1) to the gasket (2) being ascertained by means of the feedback light signal. By means of the detection module, the fastening state of the fastening device can be permanently and reliably detected. The invention further relates to a fastening system comprising the detection module.

Description

Technical Field

[0001] The present application relates to a detection module for detecting a fastening device and a fastening system comprising such a detection module. Background Art

[0002] For example, in buildings, such as bridges or tunnels, or in large technical equipment such as wind power generation equipment, fastening devices, especially threaded fastening devices, can be used. These fastening devices need to maintain a stable fastening state for a long time to avoid work safety risks. The loosening of the fastening device may be caused by various reasons, such as aging of the concrete foundation receiving the fastening device, fatigue or material creep of the fastening device itself, intentional or unintentional loosening by humans, external vibration interference, etc. The fastening state of the fastening device can be manually detected in a known manner. However, such manual detection is consuming and cannot detect the fastening state of the fastening device in real time, so it may not be possible to eliminate the work safety risk in time.

[0003] A connecting bolt is known in German patent document DE102021211044A1, which includes an optical fiber cable with a fiber Bragg grating that penetrates the bolt in the axial direction. Here, the optical fiber cable and the connecting bolt are to be designed and provided together, and the connecting bolt needs to have structural measures that are difficult to process in order to accommodate the optical fiber cable. In addition, the optical fiber cable penetrates the connecting bolt, which significantly limits the application range of the detection system including the optical fiber cable. Summary of the invention

[0004] The purpose of the present application is to provide a detection module for detecting a fastening device, especially a threaded fastening device, and a fastening system, especially a threaded fastening system, comprising such a detection module, by means of which the fastening state of the fastening device can be reliably and timely detected, preferably in particular the loosening of the fastening device can be detected.

[0005] A first aspect of the present invention relates to a detection module for detecting a fastening device, in particular a threaded fastening device. The detection module comprises:

[0006] - a gasket configured to be clamped by a fastening device with a predetermined fastening force;

[0007] - an optical fiber cable extending transversely in the gasket, the optical fiber cable having a fiber Bragg grating (FBG) assigned to the gasket, the fiber Bragg grating being able to undergo stress deformation in response to a clamping force applied to the gasket by the fastening means; and

[0008] a control unit connected to the fiber optic cable, which is capable of receiving and processing a feedback optical signal generated by means of the fiber Bragg grating, wherein the clamping force and / or a change in the clamping force applied by the fastening device to the gasket can be ascertained by means of the feedback optical signal.

[0009] The detection module according to the present invention can work for a long time, reliably and at low cost. As an optical sensor, FBG can be free from electromagnetic interference and can be placed in an electromagnetic environment without the risk of interference and signal loss; it can be wrapped in a gasket and can withstand environmental influences, such as dust, moisture and other harsh environmental influences. In addition, FBG itself does not require power supply.

[0010] In particular, when the detection module is used in large structures such as tunnels or bridges, the detection module can be assigned to a large number of fastening devices, which can be detected and / or monitored by the same detection module, which can be particularly cost-effective.

[0011] In some embodiments, the fastening device may be a threaded fastening device, such as a screw without a nut, a bolt with a nut, a stud, an expansion bolt, or the like.

[0012] In some embodiments, the fastening device may be a fastening device without threads. One example is a push rivet device, which includes a sleeve and a push rivet that can be pushed into the sleeve under the application of axial force. In another example, a bolt element includes barbs that are consecutive to each other, and a locking element can be sleeved on the bolt element and pushed along the bolt element in one direction, but cannot be pulled out in the opposite direction, wherein the locking element is blocked by the barbs when being pulled out in the opposite direction.

[0013] In some embodiments, the control unit is integrated with a light source or connected to a light source, and the control unit is capable of controlling the light source to output a detection light signal to the optical fiber cable.

[0014] The control unit is integrated with an alarm device or connected to the alarm device, and the control unit can control the alarm device to output alarm information when a clamping force change corresponding to a predetermined looseness degree of the fastening device is found.

[0015] In some embodiments, the control unit is integrated with a display device or connected to a display device, and the display device can display the detection performed by the detection module.

[0016] In some embodiments, the detection module includes a plurality of gaskets, which are connected in series via a common optical fiber cable, each gasket is assigned to a corresponding fastening device and is equipped with a corresponding FBG, wherein each FBG of each gasket has a different central wavelength of the reflection spectrum, and the control unit is capable of ascertaining the clamping force and / or clamping force change applied by the assigned fastening device to the assigned gasket based on the feedback optical signal generated by means of each FBG.

[0017] In some embodiments, the number of the spacers may be ≥3, such as ≥5, such as ≥10, or ≥15, or ≥20.

[0018] In some embodiments, the number of the shims may be ≤1000, such as ≤500 or 200 or 100, such as ≤80, such as ≤60, or ≤40, or ≤20.

[0019] In some embodiments, the detection module includes two or more (eg, three or four) parallel fiber optic cables, the two or more fiber optic cables are connected to a common control unit, and each fiber optic cable connects the plurality of gaskets in series.

[0020] In some embodiments, one of the optical fiber cables is operatively connected to the control unit, and the remaining optical fiber cables are configured as redundant optical fiber cables and can be switched to be operatively connected to the control unit, respectively.

[0021] In some embodiments, each optical fiber cable can be operatively connected to the control unit in sequence in a detection cycle, so that multiple detection results can be obtained for the same gasket or the same fastening device through multiple FBGs, and these detection results can be used for averaging or otherwise used jointly.

[0022] In some embodiments, the detection module has a temperature compensation structure for FBG.

[0023] In some embodiments, the temperature compensation structure includes a first member of the gasket and a second member of the optical fiber cable having a FBG.

[0024] In some embodiments, the first component and the second component are made of materials with different thermal expansion coefficients, and the first component can resist the influence of temperature changes on the second component.

[0025] In some embodiments, the first component is a recess, preferably a bore, of the gasket, and the second component is a fiber inlay, preferably a cylinder, of the optical fiber cable having an FBG, the fiber inlay being accommodated in the recess, and the thermal expansion coefficient of the material of the gasket is greater than the thermal expansion coefficient of the material of the fiber inlay.

[0026] In some embodiments, the thermal expansion coefficient of the material of the gasket is 1.5 to 2.5 times, particularly 1.8 to 2.2 times, preferably 1.9 to 2.1 times, such as about 2, of the thermal expansion coefficient of the material of the optical fiber inlay.

[0027] In some embodiments, the gasket is made of a metal material, such as a steel material or an aluminum material, and / or the optical fiber cable is made of glass fibers.

[0028] In some embodiments, the gasket has two surfaces facing each other.

[0029] In some embodiments, at least one of the two surfaces is uneven, preferably with embossing. The uneven surface can promote that the clamping force applied to the gasket by the fastening device causes stress deformation of the fiber optic cable section received in the gasket.

[0030] In some embodiments, one of the first surfaces is flat and the other surface has embossments configured such that a clamping force applied to the gasket by a fastening device induces stress deformation of a fiber optic cable segment received in the gasket via the embossments.

[0031] In some embodiments, the fiber optic cable section received in the gasket extends in a plane orthogonal to the through hole of the gasket in an unloaded initial state of the gasket, for example, linearly or curvilinearly.

[0032] In principle, the fiber-optic cable section of the fiber-optic cable received in the gasket can extend arbitrarily in the base body of the gasket, for example in the form of a three-dimensional curve.

[0033] In some embodiments, the gasket is constructed in two pieces, including two gasket parts connected to each other.

[0034] In some embodiments, a wire groove for receiving the optical fiber cable is formed in the side of one of the gasket components facing the other gasket component, or each gasket component forms a half of a wire groove in the side thereof facing the corresponding other gasket component.

[0035] In some embodiments, the wire groove has a V-shaped cross section, or a half of the wire groove has a V-shaped cross section.

[0036] In some embodiments, the optical fiber cable is fixed in the cable groove of the gasket for receiving the optical fiber cable in a material-locked manner, in particular, in an adhesive manner.

[0037] In some embodiments, the gasket has a through hole for passing the fastening device.

[0038] A second aspect of the present invention relates to a fastening system, which comprises a fastening device and a detection module for detecting the fastening device according to the first aspect of the present invention.

[0039] It goes without saying that any one or more of the optional features of the detection module according to the first aspect of the present invention can form optional features of the threaded fastening system.

[0040] In some embodiments, the fastening device is a threaded fastening device, such as a bolt connection device or an expansion bolt.

[0041] In some embodiments, the fastening system includes a plurality of fastening devices, each fastening device is equipped with a corresponding gasket, and the detection module includes each gasket. The number of fastening devices may correspond to the number of gaskets mentioned above. For example, in a tunnel of several kilometers, a fastening device may be arranged at a certain distance (e.g., 50 meters).

[0042] In some embodiments, each fastening device may be constructed identically. Alternatively, each fastening device may be constructed differently.

[0043] The technical features mentioned above, the technical features to be mentioned below, and the technical features shown separately in the drawings can be combined with each other arbitrarily, as long as the combined technical features are not contradictory. All feasible feature combinations are technical contents clearly recorded in this article. Any of the multiple sub-features contained in the same sentence can be applied independently, and does not have to be applied together with other sub-features. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The invention will now be explained in more detail by means of illustrative, non-limiting embodiments with reference to the accompanying schematic drawings.

[0045] Figure 1 1 is a schematic diagram of a fastening system according to an embodiment of the present invention.

[0046] Figure 2 yes Figure 1 A schematic partial view of a fastening system of FIG. 1 in an exemplary installed state with respect to a single fastening device.

[0047] Figure 3 and Figure 4 yes Figure 1 Detailed front and side views of a fastening system of FIG. 1 in an exemplary mounted state with respect to a single fastening device.

[0048] Figure 5It is a schematic diagram used to describe the temperature compensation measures of the detection module. DETAILED DESCRIPTION

[0049] The following will describe exemplary embodiments of the present application with reference to the accompanying drawings. However, it should be understood that the present application can be presented in a variety of different ways and is not limited to the embodiments described below. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide more additional embodiments. In all drawings, the same reference numerals may represent the same or functionally identical elements.

[0050] Figure 1 1 is a schematic diagram of a fastening system according to an exemplary embodiment of the present invention. The fastening system comprises an optical fiber cable 20 having a certain number n of fiber Bragg gratings (FBGs) 18 spaced apart from one another. In principle, the number n of FBGs 18 can be arbitrary, for example n=1, 2, 3, 4, 5 or 6, for example n≥10 or 15 or 20. Preferably, n≤1000 or 500 or 100 or 50. Figure 1 In the example of FIG. 2 , two FBGs 18 are described. In the case of having multiple FBGs 18 on the same optical fiber cable, they may have different characteristic reflection spectrum center wavelengths. Each FBG 18 may be provided to a Figure 1 With the aid of the FBG 18, an associated fastening device, in particular a fastening force and / or a change in the fastening force of the associated fastening device, can be detected.

[0051] The optical fiber cable 20 is connected to the control unit 10, and the control unit 10 can determine the tightening force and / or tightening force change of the tightening device according to the feedback optical signal 19 obtained by means of the FBG 18. The control unit can be integrated with the light source 11, or connected to a separate light source. The light source 11 can emit a detection optical signal 14 to the optical fiber cable 20, and each FBG 18 on the optical fiber cable 20 generates a corresponding feedback optical signal 19, especially a reflected optical signal after being incident by the detection optical signal 14, and the reflected optical signal has a predetermined reflection spectrum center wavelength. The control unit 20 may include a device for receiving and analyzing the reflected optical signal, and the device may include a Fabry-Perot interferometer 12. When a tightening device has a predetermined tightening force, the FBG 18 assigned to the tightening device generates a reflected optical signal with a predetermined reflection spectrum center wavelength. When the tightening force of the tightening device changes, the reflected optical signal of the FBG 18 assigned to the tightening device changes accordingly. Therefore, when the change degree of the reflected light signal reaches or exceeds the threshold value, it can be inferred that the change of the fastening force of the associated fastening device exceeds the tolerable degree, for example, the fastening device has reached a loose state.

[0052] Additionally, the control unit 10 can cause the generation of an alarm message. To this end, the control unit 10 can be integrated with an alarm device or connected to a separate alarm device. The alarm message can be in the form of, for example: a text or graphic warning on the display screen 13, and / or an acoustic alarm, and / or an optical alarm.

[0053] In an exemplary application of the fastening system in a tunnel, a fastening device, especially a threaded fastening device, is arranged at regular intervals on the wall of a tunnel several kilometers long, and these fastening devices are connected to a common control unit 10 via a common optical fiber cable 20. These fastening devices can be used to fix various loads, such as cables or lighting devices. In addition to the control unit 10, the detection module of the fastening system does not require power or other energy sources, is not subject to electromagnetic interference, and can stably detect or monitor the fastening force and / or fastening force changes of each fastening device for a long time. In particular, when any fastening device is loose, the loosening of the fastening device can be promptly notified so that countermeasures can be taken in time to eliminate safety risks in time.

[0054] It goes without saying that the fastening devices associated with one and the same optical fiber cable 20 can be constructed identically, or differently, for example they can be of the same type but with different dimensions or other parameters, or for example they can be of different types.

[0055] Figure 2 yes Figure 1 Schematic diagram of a detail of a fastening system of FIG. 1 in an exemplary installed state with respect to a single fastening device 1 . Figure 3 and Figure 4 yes Figure 1 1 and 2 show a front view and a side view of a detail of a fastening system in an exemplary installed state with respect to a single fastening device 1 .

[0056] The fastening device 1 is configured as a threaded fastening device, more specifically as a screw, which is mounted on a concrete wall 3, and a gasket 2 is clamped between the head of the fastening device 1 and the concrete wall 3. The concrete wall 3 may be provided with a mounting base 22 and a mounting hole 21 for receiving the rod of the fastening device 1. The fastening device 1 passes through the through hole 4 of the gasket 2 and extends into the concrete wall 3. When the fastening device 1 is mounted on the concrete wall 3 with a predetermined fastening force, the gasket 2 is clamped with a predetermined clamping force. The optical fiber cable 20 extends transversely in the gasket 2. The optical fiber cable 20 has an FBG 18 assigned to the gasket, and the FBG 18 is configured to detect the clamping force and / or clamping force change applied to the gasket 2 by the fastening device 1. As an alternative to a screw without a nut, the fastening device 1 can be a bolt connection device with a nut, an expansion bolt or a similar threaded fastening device, or it can also be a fastening device without threads, such as a push rivet device or a fastening device with a barb structure.

[0057] Figure 3 and Figure 4 and Figure 2 Describe the details of the detection module in more detail.

[0058] The gasket 2 can be constructed in two parts, including two gasket parts 5 and 6 connected to each other, wherein the wire groove 15 for receiving the optical fiber cable 20 can be constructed only in one of the first gasket parts, and the other second gasket part closes the wire groove when it is connected to the first gasket part. The wire groove 15 can have a V-shaped cross section. Alternatively, each gasket part 5, 6 can form a half of the wire groove 15 in its side facing the corresponding other gasket part. Each half can have a V-shaped cross section. The wire groove 15 or the wire groove half with a V-shaped cross section can be easily processed when manufacturing the gasket 2. The two gasket parts 5, 6 can be bonded to each other or connected to each other in other suitable ways, such as soldering, press-fit connection, etc.

[0059] The fiber optic cable section of the fiber optic cable 20 received in the gasket 2 can extend transversely, for example, straightly or curvilinearly, in the gasket 2 in the unloaded initial state of the gasket 2. The fiber optic cable 20 can be fixed in the cable groove 15 of the gasket 2 for receiving the fiber optic cable 20 in a material-locked manner, especially by glue in an adhesive manner.

[0060] The first gasket component 5 can have a first surface 8 of the gasket 2 , which can be a flat surface and can be pressed against the concrete wall 3 or the mounting base 22 by the head of the fastening device 1 in the installed state of the gasket 2 .

[0061] The second gasket component 6 may have a second surface 9 of the gasket 2, which may be uneven, for example, may have embossing 7. The second surface 9 may face the installation base, for example, the concrete wall 3 or the installation base 22 in the installed state of the gasket 2. The embossing 7 may be configured so that the clamping force applied to the gasket 2 by the fastening device 1 causes stress deformation of the optical fiber cable section received in the gasket 2 via the embossing 7. The stress deformation may cause a change in the central wavelength of the reflection spectrum of the FBG 18. Therefore, by detecting the reflected light signal by the control unit 10, the stress deformation can be detected, and / or the degree of change of the stress deformation can be detected, and thus the clamping force and / or the clamping force change of the gasket 2 can be detected, and finally the fastening force and / or the fastening force change of the fastening device 1 can be detected, for example, the loosening of the fastening device 1 can be detected.

[0062] like Figure 5 As shown, as an improvement measure, the detection module may have a temperature compensation structure for FBG 18, and the temperature compensation structure may include a first component of the gasket 2 and a second component of the optical fiber cable 20 having FBG 18, the first component and the second component are made of materials with different thermal expansion coefficients, and the first component can resist the influence of temperature changes on the second component. Figure 5 In the embodiment shown, the first component is a recess 16, preferably a bore, of the gasket 2, and the second component is a fiber inlay 17, preferably a cylinder, having an FBG 18 of the optical fiber cable 20. The optical fiber inlay 17 is accommodated in the recess 16 and fixed in the recess 16 by gluing. The thermal expansion coefficient of the material of the gasket 2 is greater than the thermal expansion coefficient of the material of the optical fiber inlay 17. It is conceivable that the thermal expansion coefficient of the material of the gasket 2 is 1.5 to 2.5 times, in particular 1.8 to 2.2 times, preferably 1.9 to 2.1 times, for example approximately 2 times, of the thermal expansion coefficient of the material of the optical fiber inlay 17. According to an advantageous material combination, the gasket 2 is made of a steel material, and the optical fiber cable (including the optical fiber inlay 17) is made of glass fiber. The thermal expansion coefficient of the steel material can be approximately 12×10 -6 / K, the thermal expansion coefficient of the glass fiber can be about 6×10 -6 / K.

[0063] When the temperature rises, the optical fiber inlay 17 undergoes thermal expansion; the gasket 2 also undergoes thermal expansion, causing the diameter of the recess 16 to decrease, and thereby compressing the optical fiber inlay 17 accommodated in the recess 16. The compression of the optical fiber inlay 17 by the gasket 2 can at least partially offset the thermal expansion of the optical fiber inlay 17, and thereby at least partially - and ideally completely - eliminate the effect of temperature changes on the performance of the FBG 18. When the temperature drops, the temperature compensation structure can function similarly.

[0064] In addition, if Figure 3 and Figure 5 As shown, the detection module may include two parallel fiber optic cables 20, the two fiber optic cables 20 are connected to the common control unit 10, each fiber optic cable 20 connects the multiple gaskets 2 in series, extends transversely in each gasket 2 and has a FBG 18 assigned to the gasket 2. One of the fiber optic cables 20 is effectively connected to the control unit 10, and the other fiber optic cable 20 is configured as a redundant fiber optic cable and can be switched to be effectively connected to the control unit. When one of the fiber optic cables fails, the other fiber optic cable can be switched from a standby state to an effective state. Compared with only setting a single fiber optic cable 20, setting two parallel fiber optic cables 20 or setting more parallel fiber optic cables can improve the reliability and service life of the detection module.

[0065] In a particularly advantageous embodiment, in the unloaded initial state of the gasket 2, the optical fiber cable section of the optical fiber cable 20 in the gasket 2 extends straight, and the FBG 18 has a first reflection spectrum center wavelength. In this case, in the installed state, the fastening device 1 applies a predetermined clamping force to the gasket 2, and the clamping force squeezes the embossing 7 of the gasket 2, so that the optical fiber cable section undergoes stress bending, and the FBG 18 has a second reflection spectrum center wavelength that is changed relative to the first reflection spectrum center wavelength. If the fastening device 1 is completely loosened, the clamping force applied to the gasket 2 by the fastening device 1 is removed, the gasket 2 returns to the unloaded initial state, and the FBG 18 has the first reflection spectrum center wavelength again. The state of the fastening device 1 can be ascertained by the change in the reflection spectrum center wavelength of the feedback optical signal generated by the FBG 18.

[0066] In an alternative embodiment, in the unloaded initial state of the gasket 2, the optical fiber cable section of the optical fiber cable 20 in the gasket 2 extends in a curved manner, and the FBG 18 has a first reflection spectrum center wavelength. In this case, in the installed state, the fastening device 1 applies a predetermined clamping force to the gasket 2, and the clamping force presses the embossing 7 of the gasket 2, so that the optical fiber cable section undergoes stress bending, and the stress bending offsets the initial bending of the optical fiber cable section under no load, and the FBG 18 has a second reflection spectrum center wavelength that is changed relative to the first reflection spectrum center wavelength. If the fastening device 1 is completely loosened, the clamping force applied to the gasket 2 by the fastening device 1 is removed, the gasket 2 returns to the unloaded initial state, the optical fiber cable section has the initial bending again, and the FBG 18 has the first reflection spectrum center wavelength again. The state of the fastening device 1 can be ascertained by the change in the reflection spectrum center wavelength of the feedback optical signal generated by the FBG 18.

[0067] It should be noted that the terms used herein are for the purpose of illustrating specific aspects only and are not intended to limit the disclosure. As used herein, the singular forms "a" and "the one" shall include the plural forms unless the context clearly states otherwise. It is understood that the terms "include" and "comprises" and other similar terms, when used in the application documents, specify the existence of the stated operations, elements and / or parts, without excluding the existence or addition of one or more other operations, elements, parts and / or combinations thereof. As used herein, the term "and / or" includes all arbitrary combinations of one or more related enumerated items. In the description of the drawings, similar reference numerals always represent similar elements.

[0068] The thickness of the elements in the accompanying drawings can be exaggerated for the sake of clarity. It is also understood that if an element is referred to as being on another element, coupled to another element or connected to another element, then the element can be directly formed on the other element, coupled to it or connected to it, or one or more intervening elements can be arranged between them. On the contrary, if the expressions "directly on...", "directly coupled to..." and "directly connected to..." are used herein, then there is no intervening element. Other words used to illustrate the relationship between elements should be similarly interpreted, such as "between..." and "directly between...", "attachment" and "direct attachment", "adjacent" and "directly adjacent", etc.

[0069] Terms such as "top," "bottom," "above," "below," "above," "below," etc. are used herein to describe the relationship of one element, layer or region to another element, layer or region as illustrated in the drawings. It will be understood that these terms are intended to encompass other orientations of the device in addition to the orientation depicted in the drawings.

[0070] It is to be understood that although the terms "first", "second", etc. may be used herein to describe different elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Therefore, the first element may be referred to as the second element without departing from the teachings of the present invention.

[0071] It is also conceivable that all exemplary embodiments disclosed herein can be combined with one another in any desired manner.

[0072] Finally, it should be pointed out that the above embodiments are only used to understand the present invention, and do not limit the protection scope of the present invention. For those skilled in the art, modifications can be made based on the above embodiments, and these modifications do not depart from the protection scope of the present invention.

Claims

1. A detection module for detecting a fastening device, especially a threaded fastening device, characterized in that: The detection module comprises: - a gasket (2) configured to be clamped by the fastening device (1) with a predetermined fastening force; - an optical fiber cable (20) extending transversely in the gasket, the optical fiber cable having a fiber Bragg grating (18) assigned to the gasket, the fiber Bragg grating being capable of stress deformation in response to a clamping force applied to the gasket by the fastening means; and - a control unit (10) connected to the optical fiber cable, which is capable of receiving and processing a feedback optical signal (19) generated by means of the fiber Bragg grating, wherein the clamping force and / or a change in the clamping force applied by the fastening device to the gasket can be ascertained by means of the feedback optical signal.

2. The detection module for detecting a fastening device according to claim 1, characterized in that: The control unit (10) is integrated with a light source (11) or is connected to the light source, and the control unit is capable of controlling the light source to output a detection light signal to the optical fiber cable; and / or The control unit (10) is integrated with an alarm device or connected to the alarm device, and the control unit can control the alarm device to output alarm information when a clamping force change corresponding to a predetermined looseness degree of the fastening device is detected; and / or The control unit (10) is integrated with a display device (13) or is connected to a display device, and the display device is capable of displaying the detection performed by the detection module.

3. The detection module for detecting a fastening device according to claim 1 or 2, characterized in that: The detection module comprises a plurality of gaskets (2), which are connected in series via a common optical fiber cable (20), each gasket being assigned to a corresponding fastening device (1) and being provided with a corresponding fiber Bragg grating (18), wherein each fiber Bragg grating of each gasket has a different central wavelength of a reflection spectrum, and the control unit (10) is capable of detecting the clamping force and / or clamping force change applied by the associated fastening device to the associated gasket based on a feedback optical signal generated by each fiber Bragg grating.

4. The detection module for detecting a fastening device according to claim 3, characterized in that: The detection module includes two or more parallel optical fiber cables (20), which are connected to the common control unit (10), each optical fiber cable connects the multiple gaskets in series, one of the optical fiber cables is effectively connected to the control unit, and the remaining optical fiber cables are configured as redundant optical fiber cables and can be switched to be effectively connected to the control unit respectively.

5. The detection module for detecting a fastening device according to any one of claims 1 to 4, characterized in that: The detection module has a temperature compensation structure for a fiber Bragg grating, and the temperature compensation structure includes a first component of the gasket and a second component of the optical fiber cable having the fiber Bragg grating, the first component and the second component are made of materials with different thermal expansion coefficients, and the first component can resist the influence of temperature changes on the second component.

6. The detection module for detecting a fastening device according to claim 5, characterized in that: The first component is a recess (16), preferably a drilled hole, of the gasket (2), the second component is a fiber inlay (17) of the optical fiber cable (20) having the fiber Bragg grating (18), the fiber inlay being accommodated in the recess, the thermal expansion coefficient of the material of the gasket being greater than the thermal expansion coefficient of the material of the fiber inlay.

7. The detection module for detecting a fastening device according to claim 5 or 6, characterized in that: The thermal expansion coefficient of the material of the gasket is 1.5 to 2.5 times, in particular 1.8 to 2.2 times, preferably 1.9 to 2.1 times, for example about 2, of the thermal expansion coefficient of the material of the optical fiber inlay.

8. The detection module for detecting a fastening device according to any one of claims 5 to 7, characterized in that: The spacer is composed of a steel material, and the optical fiber cable is composed of glass fibers.

9. The detection module for detecting a fastening device according to any one of claims 1 to 8, characterized in that: The gasket has two surfaces opposite to each other, wherein a first surface (8) is flat and the other second surface (9) has embossing (7), wherein the embossing is configured such that a clamping force applied to the gasket by a fastening device causes stress deformation of a section of the optical fiber cable received in the gasket via the embossing.

10. The detection module for detecting a fastening device according to any one of claims 1 to 9, characterized in that: The fiber optic cable section of the fiber optic cable received in the gasket extends in a plane orthogonal to the thickness of the gasket in an unloaded initial state of the gasket, for example in a straight line or in a curvilinear manner.

11. The detection module for detecting a fastening device according to any one of claims 1 to 10, characterized in that: The gasket is constructed in two parts, including two gasket components (5, 6) connected to each other, wherein a wire groove for accommodating an optical fiber cable is formed in the side of one of the gasket components facing the other gasket component, or each gasket component forms a half of a wire groove in its side facing the corresponding other gasket component.

12. The detection module for detecting a fastening device according to any one of claims 1 to 11, characterized in that: The optical fiber cable is fixed in a material-bonded manner, in particular, in an adhesively bonded manner, in a cable groove of the gasket for receiving the optical fiber cable.

13. The detection module for detecting a fastening device according to any one of claims 1 to 12, characterized in that: The gasket has a through hole for the fastening device to pass through.

14. A fastening system, comprising a fastening device, preferably a threaded fastening device, more preferably a bolt connection device or an expansion bolt, characterized in that: The fastening system further comprises a detection module for detecting the fastening device according to any one of claims 1 to 13.

15. The threaded fastening system according to claim 14, characterized in that The fastening system includes a plurality of fastening devices, each fastening device is equipped with a corresponding gasket, and the detection module includes each gasket.

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