Bolt looseness detection device and method

Abstract

The invention provides a bolt looseness detection device and method, and relates to the technical field of part detection, the device comprises a conductive fixing ring, the conductive fixing ring sleeves the outer side of a bolt, and the conductive fixing ring is provided with a contact boss; the rotating cap is arranged on a nut or a bolt column head, a conductive reed is arranged on the rotating cap, the conductive reed is in contact with the contact boss to form a detection circuit, and the detection circuit is used for being electrically connected with a detection assembly. A rotary cover and a conductive reed are arranged on a bolt column head / nut, and a conductive fixing ring is arranged on a fastened piece, so that a closed detection circuit can be formed by the conductive reed and the conductive fixing ring when a bolt is fastened; once the bolt is loosened, the conductive reed is driven to be separated from the conductive fixing ring, the detection circuit is immediately switched off, and the loosening condition of the bolt can be detected by monitoring the on-off state of the detection circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of parts detection, and in particular to a bolt loosening detection device and method. Background Art

[0002] Bolt connection is the most widely used connection method in engineering practice. Bolts will suffer fatigue damage and loosening under the action of cyclic load and forced vibration. Once the bolts are loose, the failure of the fastening effect may cause serious consequences. Therefore, it is very necessary to detect the looseness of the bolts in engineering.

[0003] Existing bolt loosening detection mainly includes methods such as using piezoelectric sensors, electromagnetic waves / ultrasonic waves, optical principles, and electromagnetic induction coils. However, these existing detection methods have defects such as high power consumption, susceptibility to environmental interference, or restrictions on the size and shape of the bolts. Therefore, it is urgent to propose a new bolt loosening detection scheme to solve the problems of the existing technology. Summary of the invention

[0004] The purpose of the present invention is to provide a bolt loosening detection device and method to improve the above problem. In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0005] In a first aspect, the present application provides a bolt loosening detection device, comprising:

[0006] A conductive fixing ring, which is sleeved on the outer side of the bolt and has a contact boss;

[0007] A rotating cap is arranged on the nut or bolt stud, and a conductive spring is arranged on the rotating cap. The conductive spring contacts the contact boss to form a detection circuit, and the detection circuit is used to be electrically connected to the detection component.

[0008] Optionally, the conductive fixing ring includes a first wedge-shaped gasket and a second wedge-shaped gasket;

[0009] The first wedge-shaped gasket is fixed to the bolt stud or the nut, and the second wedge-shaped gasket is fixed to a fastener, wherein the fastener is an object fixed by the bolt;

[0010] The first wedge-shaped gasket is provided with a first wedge-shaped tooth, the second wedge-shaped gasket is provided with a second wedge-shaped tooth, and the first wedge-shaped tooth and the second wedge-shaped tooth are engaged with each other;

[0011] The included angles between the first wedge-shaped teeth and the second wedge-shaped teeth and the plane of the conductive fixing ring are greater than the thread angle of the bolt.

[0012] Optionally, the first wedge-shaped gasket is provided with first fine teeth on a surface facing the bolt stud or nut;

[0013] The second wedge-shaped gasket is provided with second fine teeth on a surface facing the fastened member.

[0014] Optionally, the device further comprises a fixing cap, and the rotating cap is arranged on the stud of the nut or bolt through the fixing cap;

[0015] The fixing cap is provided with a fixing groove, and the nut or bolt stud is fixed in the fixing groove;

[0016] The rotating cap is buckled on the fixed cap, a first constraint structure is provided on the outer side of the fixed cap, and a second constraint structure is provided on the inner side of the rotating cap. The second constraint structure limits the first structure through structural limitation or friction limitation, so that the rotational resistance between the second constraint structure and the first structure is greater than the rotational resistance between the conductive spring sheet and the contact boss.

[0017] Optionally, one end of the fixing cap in contact with the rotating cap is provided with a chamfer or a rounded corner.

[0018] Optionally, the detection component includes a power supply, a processing circuit and an alarm module;

[0019] The power supply is connected to the detection circuit to form a power-on loop;

[0020] The processing circuit is connected to the power-on circuit, and the processing circuit is configured to obtain an on / off signal of the power-on circuit;

[0021] The alarm module is connected to the processing circuit.

[0022] Optionally, one end of the conductive spring is connected to the side of the rotating cap, and the other end is provided with a U-shaped slot, and the contact boss is snapped into the U-shaped slot;

[0023] The opening direction of the U-shaped slot is opposite to the loosening rotation direction of the screw rod or the nut.

[0024] Optionally, the fastened piece is made of a conductive material, and the conductive spring, the conductive fixing ring and the fastened piece are connected in sequence to form a detection circuit.

[0025] Optionally, the conductive reed includes a first conductive reed and a second conductive reed;

[0026] The contact boss comprises a first contact boss and a second contact boss;

[0027] The first conductive spring piece contacts the first contact boss, and the second conductive spring piece contacts the second contact boss.

[0028] Optionally, an insulating layer is provided on a side of the conductive fixing ring away from the rotating cap, and the first conductive reed, the conductive fixing ring and the second conductive reed are connected in sequence to form a detection circuit.

[0029] In a second aspect, the present application also provides a method for detecting bolt loosening, comprising the steps of:

[0030] The bolt loosening detection device based on the present application obtains the on-off signal of the detection circuit through the detection component;

[0031] According to the on-off signal, it is determined whether the bolt is loose, and if the bolt is loose, an alarm signal is sent to the monitoring device.

[0032] The beneficial effects of the present invention are:

[0033] The present application sets a rotating cover and a conductive spring on the bolt stud / nut, and sets a conductive fixing ring on the fastener, so that the conductive spring and the conductive fixing ring can form a closed detection circuit when the bolt is tightened; once the bolt is loosened, it will drive the conductive spring to separate from the conductive fixing ring, and the detection circuit will be disconnected immediately. The loosening of the bolt can be detected by monitoring the on-off state of the detection circuit. Compared with the existing bolt loosening detection device, the circuit of the present invention is simple, the wiring amount is low, the installation and use cost is low, and the application range is wide, and it is not easily affected by the external environment.

[0034] Other features and advantages of the present invention will be set forth in the following description, and in part will become apparent from the description, or may be understood by practicing embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0036] Figure 1 This is a schematic diagram of the structure of a bolt loosening detection device in an embodiment of the present application;

[0037] Figure 2 This is a schematic diagram of the structure of the first wedge-shaped gasket and the second wedge-shaped gasket in the embodiment of the present application;

[0038] Figure 3 This is a schematic diagram of the structure of the ring member in the embodiment of the present application;

[0039] Figure 4This is a schematic diagram of the structure of a rotating cap in the form of a clamp in an embodiment of the present application;

[0040] Figure 5 This is a schematic diagram of the U-shaped slot structure in an embodiment of the present application;

[0041] Figure 6 This is a schematic diagram of the structure of the spring sheet (side compression) in the embodiment of the present application;

[0042] Figure 7 This is a schematic diagram of the structure of the spring sheet (with the upper surface pressed tightly) in the embodiment of the present application;

[0043] Figure 8 This is a schematic diagram of the structure of the detection component in the embodiment of the present application;

[0044] Fig. 9 It is a schematic diagram of a detection circuit formed by a conductive spring, a conductive fixing ring and a fastened component in an embodiment of the present application;

[0045] Fig.10 This is a schematic diagram of the insulating layer arrangement in an embodiment of the present application.

[0046] Markings in the figure: 100, conductive fixing ring; 110, contact boss; 111, first contact boss; 112, second contact boss; 120, first wedge-shaped gasket; 130, second wedge-shaped gasket; 131, second wedge-shaped tooth; 140, ring member; 200, bolt; 210, bolt stud; 300, rotating cap; 310, flexible ratchet sheet; 320, locking member; 400, nut; 500, conductive spring; 510, U-shaped slot; 520, first conductive spring; 530, second conductive spring; 540, spring sheet; 600, fastener; 700, fixing cap; 710, ratchet tooth; 720, chamfer; 800, detection component; 810, power supply; 820, processing circuit; 821, wireless communication module; 830, alarm module; 900, insulating layer. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0048] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0049] The existing bolt loosening detection technologies on the market are mainly the following:

[0050] (1) Use color changes or mechanical signs to indicate the loosening status of the bolt (anti-loosening mark). The disadvantage of this technology is that it can only provide qualitative indications and requires regular manual inspections, and cannot achieve real-time monitoring.

[0051] (2) Use a resistance strain gauge or piezoelectric sensor to measure the tension or stress of the bolt, and determine whether the bolt is loose based on a preset threshold. The disadvantage of this technology is that the resistance strain gauge or piezoelectric sensor is easily affected by the environment, the signal is easily interfered, and the installation and maintenance costs are high, which is not suitable for large-scale use.

[0052] (3) Use electromagnetic waves or ultrasonic waves to generate excitation signals inside the bolts, and reflect the tightness of the bolts by receiving characteristic parameters of the signal such as amplitude, frequency, phase, etc. The disadvantage of this technology is that it requires special instruments and operators, and has restrictions on the size and shape of the bolts, and cannot be applied to all types of bolts.

[0053] (4) Use optical principles (similar to photoelectric mouse) to measure and calculate the bolt rotation angle, thereby calculating the bolt tension or stress to achieve bolt loosening monitoring. The advantages of this technology are lightness and easy installation; but the disadvantages are high energy consumption and high cost;

[0054] (5) The principle of frequency change caused by the relative position change of the electromagnetic induction coil is used to measure and calculate the bolt rotation angle, thereby inferring the tension or stress of the bolt to achieve bolt loosening monitoring. The disadvantages of this technology are also high energy consumption and high cost. For details, please refer to Chinese patent CN202410177794.

[0055] (6) Use memory metal strain switches to measure preload and then monitor bolt loosening. The advantage of this technology is its compact structure, but its disadvantages are difficult processing, high cost, and poor weather resistance.

[0056] Therefore, the existing bolt loosening monitoring devices on the market have certain limitations and cannot meet the needs of efficient, reliable and intelligent monitoring of bolt fasteners in modern industrial production.

[0057] Example 1

[0058] like Figure 1As shown, this embodiment provides a bolt 200 loosening detection device, including:

[0059] A conductive fixing ring 100, wherein the conductive fixing ring 100 is sleeved on the outer side of the bolt 200, and a contact boss 110 is provided on the conductive fixing ring 100;

[0060] The rotating cap 300 is arranged on the nut 400 or the bolt stud 210 . The rotating cap 300 is provided with a conductive spring 500 . The conductive spring 500 contacts the contact boss 110 to form a detection circuit. The detection circuit is used to be electrically connected to the detection component 800 .

[0061] The conductive spring 500 and the contact boss 110 have a certain contact stroke, that is, the conductive spring 500 and the contact boss 110 can move relative to each other for a certain distance, and the two can maintain contact within the distance range, thereby maintaining the detection circuit closed, and the detection component 800 can continuously detect the circuit closed signal. When the bolt 200 is loose, the rotating cap 300 rotates a certain angle following the nut 400 or the bolt stud 210, and the conductive spring 500 also rotates, which will cause the conductive spring 500 to separate from the contact boss 110 and the detection circuit to be disconnected. At this time, the detection component 800 detects the circuit disconnection signal, which can determine that the bolt 200 is loose.

[0062] like Figure 2 As shown, as an optional implementation of the present application, the conductive fixing ring 100 includes a first wedge-shaped gasket 120 and a second wedge-shaped gasket 130;

[0063] The first wedge-shaped washer 120 is fixed to the bolt stud 210 or the nut 400, and the second wedge-shaped washer 130 is fixed to the fastener 600 acted upon by the bolt 200;

[0064] The first wedge-shaped gasket 120 is fixed to the bolt stud 210 or the nut 400, and the second wedge-shaped gasket 130 is fixed to the fastener 600, and the fastener 600 is an object fixed by the bolt 200;

[0065] The first wedge-shaped gasket 120 is provided with a first wedge-shaped tooth, and the second wedge-shaped gasket 130 is provided with a second wedge-shaped tooth 131, and the first wedge-shaped tooth and the second wedge-shaped tooth 131 are engaged with each other;

[0066] That is, the first wedge-shaped gasket 120 and the second wedge-shaped gasket 130 are overlapped and embedded to form a conductive fixing ring 100 , and the upper and lower surfaces of the conductive fixing ring 100 are fixed to the bolt stud 210 / nut 400 and the fastener 600 respectively.

[0067] The angle α between the first wedge-shaped tooth and the second wedge-shaped tooth 131 and the plane of the conductive fixing ring 100 is greater than the thread angle β of the bolt 200. When the bolt 200 tends to rotate and loosen, since the thread angle β is less than the wedge-shaped tooth angle α, the bolt 200 needs to overcome greater resistance to rotate and loosen. Specifically, a single wedge-shaped gasket is used as the force analysis object:

[0068] When the nut 400 (the same applies to the bolt 200) tends to loosen due to rotation, the external force (vibration, etc.) causing the loosening tendency is transmitted from the nut 400 (or the fastener 600, the bolt stud 210) material to the wedge-shaped tooth structure; because the angle α of the wedge-shaped tooth is greater than the thread angle β, there is an angle difference, and the circumferential rotation will cause axial displacement. At this time, the bolt 200 itself cannot move axially, so the force that needs to be overcome for the bolt 200 to loosen is the stress caused by the elongation of the bolt 200 itself (caused by the axial displacement tendency). Therefore, by using the conductive fixing ring 100 composed of such wedge-shaped gaskets, an additional enhanced anti-loosening effect can be obtained.

[0069] Specifically, the first wedge-shaped gasket 120 and the second wedge-shaped gasket 130 may be fixed to the fastener 600, the bolt stud 210 / the nut 400 by bonding, welding or biting. The principle is to ensure that when there is a loosening tendency caused by external force (vibration, etc.), the connection between the wedge-shaped gasket and the nut 400 (or the fastener 600, the bolt stud 210) will not be displaced or deformed.

[0070] As an optional embodiment, the first wedge-shaped gasket 120 is provided with first fine teeth on the surface facing the bolt stud 210 or the nut 400, and the first fine teeth are engaged with the bolt stud 210 or the nut 400 to maintain relative fixation;

[0071] The second wedge-shaped gasket 130 is provided with second fine teeth on the surface facing the fastened member 600 , and the second fine teeth are engaged with the fastened member 600 to maintain relative fixation.

[0072] The hardness of the first fine teeth and the second fine teeth needs to be greater than the hardness of the nut 400 (or the fastened part 600, the bolt stud 210). When installing the wedge-shaped gasket, the fine teeth can be embedded by applying pressure (such as tightening the bolt 200 / nut 400), and the surface of the bolt stud 210 / nut 400 / fastened part 600 will be deformed accordingly. Under the action of loosening external force, the material (of the fastened part 600, bolt 200, nut 400) at the bite of the fine teeth will not be deformed, and no relative displacement will occur.

[0073] The first wedge-shaped gasket 120 and the second wedge-shaped gasket 130 are preferably installed on both sides of the fastener 600, that is, the overlapping order is the bolt stud 210, the conductive fixing ring 100, the fastener 600, the conductive fixing ring 100, and the nut 400. At the same time, it can be foreseen that the bolt 200 and the nut 400 need to be removed before installing the first wedge-shaped gasket 120 and the second wedge-shaped gasket 130, so this solution is suitable for the case where the bolt 200 is removable, or the detection device of the present application is installed when the bolt 200 is installed.

[0074] like Figure 3 As shown, in another embodiment, the conductive fixing ring 100 can use a simple ring 140, the inner diameter of the ring 140 is larger than the outer diameter of the bolt stud 210 / nut 400, so that the ring 140 can be directly inserted from the bolt stud 210 / nut 400 and then fixed to the fastener 600; the fixing method of the ring 140 can be specifically bonding, welding, riveting or interlocking. The solution of the ring 140 is suitable for equipment where the bolt 200 has been installed and cannot be removed, and the detection device of the present application can be installed without removing the bolt 200.

[0075] If the ring 140 is fixed by bonding, it is preferred to open a plurality of axial holes on the ring 140, which can effectively increase the circumferential strength between the cured adhesive and the ring 140.

[0076] As an optional implementation, Figure 2 and Figure 3 As shown, the device further includes a fixing cap 700, and the rotating cap 300 is arranged on the nut 400 or the bolt stud 210 through the fixing cap 700;

[0077] The fixing cap 700 is provided with a fixing groove, and the nut 400 or the bolt stud 210 is fixed in the fixing groove; the shape and size of the fixing groove match the nut 400 or the bolt stud 210, and the fixing groove and the nut 400 or the bolt stud 210 are fixed circumferentially and axially by interference fit, bonding or riveting.

[0078] The rotating cap 300 is buckled on the fixed cap 700, and a first constraint structure is provided on the outer side of the fixed cap 700, and a second constraint structure is provided on the inner side of the rotating cap 300. The second constraint structure limits the first structure through structural limitation or friction limitation, so that the rotational resistance between the second constraint structure and the first structure is greater than the rotational resistance between the conductive spring 500 and the contact boss 110.

[0079] Specifically, in this embodiment, the first constraint structure is a ratchet tooth 710 disposed on the outside of the fixed cap 700, and the second constraint structure is a flexible ratchet piece 310 disposed on the inside of the rotating cap 300. Figure 4 and Figure 5 As shown, the tooth shape direction of the ratchet teeth 710 is opposite to the extension direction of the flexible ratchet piece 310;

[0080] The tooth profile direction of the ratchet teeth 710 is the same as the loosening rotation direction of the screw or nut 400 .

[0081] After the rotating cap 300 is installed on the fixed cap 700, the flexible ratchet piece 310 is inserted into the gap of the ratchet teeth 710. When the rotating cap 300 tends to rotate in the direction of the tooth shape of the ratchet teeth 710, it will be resisted by the flexible ratchet piece 310 and the rotation will be restricted. When the rotating cap 300 tends to rotate in the opposite direction of the tooth shape of the ratchet teeth 710, the rotation is along the extension direction of the flexible ratchet piece 310, so the rotation will not be restricted. It can be seen that by providing the ratchet teeth 710 and the flexible ratchet piece 310, the unidirectional rotation of the rotating cap 300 relative to the fixed cap 700 is achieved. When the rotating cap 300 is installed, the rotating cap 300 can be adjusted by unidirectional rotation so that the conductive spring piece 500 on the rotating cap 300 is properly in contact with the contact boss 110. When the bolt 200 is loosened, the fixing cap 700 rotates. Since the fixing cap 700 abuts against the flexible ratchet plate 310, and the abutting resistance is greater than the friction between the conductive spring 500 and the contact boss 110, the fixing cap 700 will simultaneously drive the rotating cap 300 to rotate, and the conductive spring 500 will be displaced until it is separated from the contact boss 110, and the detection circuit is disconnected.

[0082] like Figure 2 and Figure 3 As shown, in order to facilitate the installation of the rotating cap 300, a chamfer 720 is provided at one end of the fixed cap 700 that contacts the rotating cap 300. During installation, the flexible ratchet piece 310 is compressed and deformed under the guidance of the chamfer 720, so that the rotating cap 300 can be quickly buckled on the fixed cap 700. The outer diameter of the largest part (bottom surface) of the chamfer 720 structure is greater than or equal to the outer diameter of the ratchet teeth 710. When the flexible ratchet piece 310 is inserted into the gap of the ratchet teeth 710, the flexible ratchet piece 310 is limited by the bottom surface of the chamfer 720 structure, thereby limiting the separation of the rotating cap 300 in the axial direction.

[0083] In other embodiments, the first constraint structure may be a common tooth-shaped structure, and the second constraint structure may be a limit plate with elasticity, the limit plate is inserted into the gap of the tooth-shaped structure, when the bolt loosens and the external force is transmitted to the limit plate, it is not enough to cause the limit plate to be significantly deformed, and the limit plate has resistance to the tooth-shaped structure, so the rotation of the fixed cap 700 will cause the rotating cap 300 to rotate synchronously; when the rotating cap 300 is manually installed, the force applied manually is enough to cause the limit plate to be significantly deformed under the pressure of the tooth-shaped structure, that is, the applied force is greater than the resistance of the limit plate to the tooth-shaped structure, so the rotating cap 300 and the fixed cap 700 can rotate relative to each other, so that the rotating cap 300 can be adjusted to make the conductive spring 500 and the contact boss 110 properly contact. Alternatively, the first constraint structure and the second constraint structure may be two friction surfaces, and the friction resistance between the friction surfaces is greater than the friction resistance between the conductive spring 500 and the contact boss 110, which can also achieve the above-mentioned technical effects.

[0084] like Figure 4 As shown, the rotating cap 300 of the present application can also be designed in the form of a clamp, that is, the side of the rotating cap 300 surrounds the bolt stud 210 / nut 400 and is locked and fixed with a locking member 320. A conductive spring 500 is arranged on the locking member 320 or the rotating cap 300 so that the conductive spring 500 contacts the contact boss 110 to form a detection circuit.

[0085] The number of the conductive spring 500 and the contact boss 110 can be one or more.

[0086] As an implementation mode, one conductive spring 500 and one contact boss 110 are respectively provided, one end of the conductive spring 500 is connected to the side of the rotating cap 300, and the other end is provided with a U-shaped slot 510, and the contact boss 110 is snapped into the U-shaped slot 510;

[0087] The opening direction of the U-shaped slot 510 is opposite to the loosening rotation direction of the screw or nut 400 .

[0088] The structure of the U-shaped slot 510 is as follows Figure 5 As shown, the U-shaped slot 510 has a certain elasticity and can clamp the contact boss 110. When the screw or nut 400 rotates, the U-shaped slot 510 rotates, and the contact boss 110 gradually disengages from the opening of the U-shaped slot 510 until it is completely separated.

[0089] like Figure 6 and Figure 7As shown, in addition to the U-shaped slot 510, the contact between the conductive spring 500 and the contact boss 110 can also be in a single-sided compression form, that is, a spring piece 540 is set at the lower end of the conductive spring 500, and the spring piece 540 is in contact with one side or upper surface of the contact boss 110. Due to the elastic deformation of the spring piece 540, a certain pressure is generated on the contact boss 110 to ensure that the two will not separate under external interference (such as vibration).

[0090] like Figure 8 As shown, as an optional implementation of the present application, the detection component 800 includes a power supply 810, a processing circuit 820 and an alarm module 830;

[0091] The power supply 810 is connected to the detection circuit to form a power-on loop;

[0092] The processing circuit 820 is connected to the power-on circuit, and the processing circuit 820 is configured to obtain an on / off signal of the power-on circuit; the on / off signal may be obtained by measuring the current or voltage of the power-on circuit, and the on / off signal may be output in a wired manner.

[0093] The processing circuit 820 may be a simple logic circuit or a more complex circuit, including an integrated circuit (chip) or a transistor.

[0094] The processing circuit 820 is used to control the overall operation of the detection assembly 800 to complete all or part of the steps in the above-mentioned bolt 200 loosening detection method.

[0095] Preferably, the processing circuit 820 includes a wireless communication module 821, which can send an alarm control signal to a remote device via wireless communication.

[0096] The alarm module 830 is connected to the processing circuit 820. When the processing circuit 820 determines that the power circuit is disconnected according to the obtained on-off signal, an alarm control signal is sent to the alarm module 830 to remind the staff that the bolt 200 is loose. The alarm module 830 is preferably set on a remote monitoring device and is wirelessly connected to the processing circuit 820.

[0097] As an optional implementation of the present application, the detection component 800 can also use radio frequency identification technology (RFID). The RFID tag is connected to the power-on circuit, and the chip of the RFID tag can detect the on-off of the circuit. The power supply 810 can specifically use the RFID antenna rectification and filtering module. A reader is set at the remote end to read the tag in real time. When the RFID tag receives the electromagnetic wave emitted by the reader, it can use the energy of the radio wave to rectify and filter and then provide power, so that the chip can obtain the on-off state of the detection circuit, and then feed back the obtained circuit on-off information to the reader through radio waves to realize the monitoring of the circuit on-off state. The energy consumption of RFID is very low, and compared with the existing technology, it can significantly reduce the use cost of the bolt loosening detection device.

[0098] The design of the detection circuit can be divided into two cases:

[0099] like Fig. 9 As shown, if the fastened part 600 is made of conductive material and is grounded, and powering on will not affect the use of the fastened part 600, the conductive spring 500, the conductive fixing ring 100 and the fastened part 600 can be connected in sequence to form a detection circuit.

[0100] like Fig.10 As shown, in general, the conductive spring 500 can be designed to include a first conductive spring 520 and a second conductive spring 530; the contact boss 110 includes a first contact boss 111 and a second contact boss 112; the first conductive spring 520 contacts the first contact boss 111, and the second conductive spring 530 contacts the second contact boss 112, so that the first conductive spring 520, the conductive fixing ring 100 and the second conductive spring 530 are connected in sequence to form a detection circuit; optionally, if the power-on will affect the use of the fastener 600, an insulating layer 900 can be provided on the side of the conductive fixing ring 100 away from the rotating cap 300 to prevent the fastener 600 from being powered on.

[0101] The detection device of the present application converts the displacement caused by the loosening of the bolt 200 into an on-off signal of the circuit. Compared with the sensing technology using electromagnetic induction coils, electromagnetic waves or optical principles, it can effectively avoid the deviation and false alarm caused by sensor conversion and calculation; by adjusting the contact stroke between the conductive spring 500 and the contact boss 110, the threshold for judging the loosening of the bolt 200 can be set. The circuit of the device of the present application is simple, the wiring amount is low, the installation cost is low, and the application range is wide.

[0102] Example 2

[0103] The present application also provides a method for detecting a loose bolt 200, comprising the steps of:

[0104] S1. Based on the bolt loosening detection device 200 of the present application, the bolt loosening detection device 200 is installed, and the processing circuit 820 in the detection assembly 800 continuously obtains the on-off signal of the detection circuit;

[0105] S2. According to the on-off signal, determine whether the bolt 200 is loose. When the bolt 200 is loose, the conductive spring 500 is separated from the contact boss 110. The processing circuit 820 determines that the bolt 200 is loose according to the on-off signal, and sends an alarm signal to the monitoring device.

[0106] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0107] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A bolt loosening detection device, characterized in that: include: A conductive fixing ring (100), wherein the conductive fixing ring (100) is sleeved on the outer side of the bolt (200), and a contact boss (110) is provided on the conductive fixing ring (100); A rotating cap (300) is arranged on a nut (400) or a bolt stud (210), and a conductive spring (500) is arranged on the rotating cap (300). The conductive spring (500) contacts the contact boss (110) to form a detection circuit, and the detection circuit is used to be electrically connected to a detection component (800).

2. A bolt loosening detection device according to claim 1, characterized in that: The conductive fixing ring (100) comprises a first wedge-shaped gasket (120) and a second wedge-shaped gasket (130); The first wedge-shaped gasket (120) is fixed to the bolt stud (210) or the nut (400), and the second wedge-shaped gasket (130) is fixed to a fastener (600), wherein the fastener (600) is an object fixed by the bolt (200); The first wedge-shaped gasket (120) is provided with a first wedge-shaped tooth, and the second wedge-shaped gasket (130) is provided with a second wedge-shaped tooth (131), and the first wedge-shaped tooth and the second wedge-shaped tooth (131) are engaged with each other; The included angle between the first wedge-shaped tooth and the second wedge-shaped tooth (131) and the plane of the conductive fixing ring (100) is greater than the thread angle of the bolt (200).

3. A bolt loosening detection device according to claim 2, characterized in that: The first wedge-shaped gasket (120) is provided with first fine teeth on a surface facing the bolt stud (210) or the nut (400); The second wedge-shaped gasket (130) is provided with second fine teeth on the surface facing the fastened member (600).

4. A bolt loosening detection device according to claim 1, characterized in that: The device further comprises a fixing cap (700), and the rotating cap (300) is arranged on the nut (400) or the bolt stud (210) through the fixing cap (700); The fixing cap (700) is provided with a fixing groove, and the nut (400) or the bolt stud (210) is fixed in the fixing groove; The rotating cap (300) is buckled onto the fixed cap (700), a first constraint structure is provided on the outer side of the fixed cap (700), and a second constraint structure is provided on the inner side of the rotating cap (300), the second constraint structure limits the first structure by structural limitation or friction limitation, so that the rotational resistance between the second constraint structure and the first structure is greater than the rotational resistance between the conductive spring sheet (500) and the contact boss (110).

5. A bolt loosening detection device according to claim 4, characterized in that: One end of the fixing cap (700) that contacts the rotating cap (300) is provided with a chamfer (720) or a rounded corner.

6. A bolt loosening detection device according to claim 1, characterized in that: The detection component (800) includes a power supply (810), a processing circuit (820) and an alarm module (830); The power supply (810) is connected to the detection circuit to form a power-on loop; The processing circuit (820) is connected to the power-on circuit, and the processing circuit (820) is configured to obtain an on / off signal of the power-on circuit; The alarm module (830) is connected to the processing circuit (820).

7. A bolt loosening detection device according to claim 1, characterized in that: One end of the conductive spring sheet (500) is connected to the side of the rotating cap (300), and the other end is provided with a U-shaped slot (510), and the contact boss (110) is snap-fitted into the U-shaped slot (510); The opening direction of the U-shaped slot (510) is opposite to the loosening rotation direction of the screw rod or nut (400).

8. A bolt loosening detection device according to claim 2, characterized in that: The fastened part (600) is made of a conductive material, and the conductive spring sheet (500), the conductive fixing ring (100) and the fastened part (600) are connected in sequence to form a detection circuit.

9. A bolt loosening detection device according to claim 1, characterized in that: The conductive reed (500) comprises a first conductive reed (520) and a second conductive reed (530); The contact boss (110) comprises a first contact boss (111) and a second contact boss (112); The first conductive spring piece (520) contacts the first contact boss (111), and the second conductive spring piece (530) contacts the second contact boss (112).

10. A bolt loosening detection device according to claim 9, characterized in that: An insulating layer is provided on a side of the conductive fixing ring (100) away from the rotating cap (300), and the first conductive reed (520), the conductive fixing ring (100) and the second conductive reed (530) are connected in sequence to form a detection circuit.

11. A method for detecting bolt loosening, characterized in that: include: Based on the bolt loosening detection device according to any one of claims 1 to 10, an on-off signal of a detection circuit is obtained through a detection component (800); According to the on-off signal, it is determined whether the bolt (200) is loose, and if the bolt (200) is loose, an alarm signal is sent to the monitoring device.

Images