CN220982186U - Bolt loosening angle sensor - Google Patents

Abstract

The utility model discloses a bolt loosening angle sensor which is used for monitoring the relative loosening condition between a screw and a nut, wherein the bolt loosening angle sensor comprises a screw fixing component and a nut fixing component; the screw rod fixing component is used for being fixed on the screw rod and comprises a base and a bipolar magnet, and the bipolar magnet is fixed on the base; the nut fixedly connected assembly is used for being fixed on the nut and comprises a shell and a monitoring module, wherein the monitoring module is fixed on the shell and used for monitoring the magnetic field direction change of the bipolar magnet so as to monitor the loosening angle between the screw fixedly connected assembly and the nut fixedly connected assembly through monitoring the magnetic field direction change of the bipolar magnet. Compared with the prior art, the bolt loosening angle sensor monitors the loosening angle between the screw rod fixedly-connected component and the nut fixedly-connected component by utilizing the monitoring module to monitor the magnetic field direction change of the bipolar magnet, has high testing precision, is simple to install and convenient to maintain, can effectively reduce the cost, and can rapidly position the loosening bolt.

Description

Bolt loosening angle sensor

Technical Field

The application relates to the technical field of mechanical structures, in particular to a bolt loosening angle sensor.

Background

Due to factors such as vibration, metal stress, external force load and the like caused by mechanical movement, severe use environment and complex working condition, the high-strength connecting bolt used by the wind turbine generator is comprehensively influenced by various loads such as vibration, torsion and shearing for a long time in the running process, so that the high-strength connecting bolt is loosened to different degrees. Once the bolts are loosened and cannot be found in time, the stress amplitude of the bolts and the surrounding bolts is increased, vicious circle with greatly shortened fatigue life is formed, the breakage of the bolts becomes necessary, the damage of the parts is caused by light weight, if the bolts are broken and fall down, secondary damage is caused, larger maintenance cost is generated, serious safety accidents are caused by heavy weight, and huge economic loss is caused.

Attempts have been made to fix the bolts by various methods without loosening the bolts when mounting the high-strength connecting bolts, but a solution which is applicable to various bolts and can completely prevent the bolts from loosening has not been found yet. Therefore, the problem of loosening of bolts cannot be fundamentally solved.

Regular inspection of bolt loosening and timely fastening are currently a common method in various industries, and the high-strength bolts of large wind power generation towers need manual detection with the sampling rate of 100% every 3-6 months. The manual method is large in workload and long in inspection time, and moreover, the loosening condition of each bolt is difficult to accurately know, so that potential safety hazards can be caused when inspection is omitted. In order to ensure safe and stable operation of the wind turbine generator, reduce operation and maintenance cost, avoid major safety accidents of the wind turbine generator, monitor loosening angles of high-strength connecting bolts of blades and towers of the wind turbine generator, and timely strengthen the loosening bolts to avoid the occurrence of the safety accidents is an urgent need of the industry.

In the aspect of relative looseness of the monitoring screw and the nut, the traditional method comprises a moment method and a line marking method, the two methods have large workload, the monitoring is not fine enough, and manual inspection or on-machine operation is needed.

In the aspect of monitoring the bolt pretightening force, the bolt pretightening force sensor arranged on the bolt measures and calculates the time difference between the transmitted and echo electric signals by transmitting and receiving ultrasonic pulse electric signals, and judges the magnitude of the bolt pretightening force by comparing the measured time changes of the screwed state and the un-screwed state, thereby obtaining the loosening condition of the bolt. The method is complex in actual operation, high in online monitoring cost, inconvenient to install, and difficult to apply to high-strength connecting bolts, and needs to be calibrated regularly.

In the aspect of monitoring the flange gap connected with the high-strength connecting bolts, the gap between the flange plates can be monitored by installing high-precision displacement sensors at a plurality of positions of the flange plates, and the loosening condition of the high-strength connecting bolts can be indirectly identified. The method is effective only when the flange has an opening distance due to stretching and loosening of the screw rod, and the high-strength bolts of the flange plate of the wind turbine generator set are large in number, and a small amount of bolts are loosened and usually cannot generate flange clearance displacement, so that the method cannot be used for monitoring the loosening condition of the bolts.

How to realize accurate monitoring bolt looseness, and the installation is simple, the maintenance is convenient, is the technical problem that the person skilled in the art needs to solve urgently.

Disclosure of utility model

In order to solve the technical problems, the utility model aims to provide the bolt loosening angle sensor which is high in testing precision, simple to install and convenient and fast to maintain.

The technical scheme provided by the utility model is as follows:

the bolt loosening angle sensor is used for monitoring the relative loosening condition between a screw and a nut, and comprises a screw fixing component and a nut fixing component; the screw rod fixing component is used for being fixed on the screw rod and comprises a base and a bipolar magnet, and the bipolar magnet is fixed on the base; the nut fixedly connected assembly is used for being fixed on the nut and comprises a shell and a monitoring module, wherein the monitoring module is fixed on the shell and used for monitoring the magnetic field direction change of the bipolar magnet so as to monitor the loosening angle between the screw fixedly connected assembly and the nut fixedly connected assembly through monitoring the magnetic field direction change of the bipolar magnet.

Preferably, the bipolar magnet is a bipolar magnetic column, the base comprises a bottom plate and a buckling structure which is positioned on the bottom plate and matched with the bipolar magnetic column, the bipolar magnetic column is fixed on the base through the buckling structure, and the axial direction of the bipolar magnetic column is kept perpendicular to the axis of the base.

Preferably, the buckling structure comprises four buckling columns, and the bipolar magnetic columns are clamped and fixed among the four buckling columns; or the buckling structure comprises two buckling pieces forming an arc-shaped enclasping structure, and the bipolar magnetic column is pressed and fixed between the two buckling pieces.

Preferably, the fastening structure is located on a side of the base bottom plate facing the screw or on a side of the base bottom plate facing away from the screw.

Preferably, the magnetic field identification device comprises a first group of magnetic field identifications corresponding to the magnetic poles of the bipolar magnet, wherein the first group of magnetic field identifications are positioned at the periphery of the base;

and/or a second set of magnetic field signatures, the second set of magnetic field signatures being located at the perimeter of the housing;

And/or a third group of magnetic field marks, wherein the third group of magnetic field marks are positioned on the base and are respectively arranged at two ends of the bipolar magnet.

Preferably, the base is fixed on the screw rod in a threaded connection or clamping manner.

Preferably, a space exists between the base and the shell in the axial direction of the screw rod so as to avoid the base from abutting against the shell after the bolt loosens.

Preferably, the housing comprises a mating housing and cover plate, the housing and cover plate forming a cavity to secure and encapsulate the monitoring module in the cavity.

Preferably, the housing includes a top plate and a fixing portion formed by the top plate extending downward to be fixed to the nut.

Preferably, the fixing part comprises a plurality of support bars, and the ends of the support bars are fixed to the nuts through the clamping bands.

Preferably, the clamp comprises a clamping ring for encircling the outer edge of the support bar and a clamping piece for tightening the clamping ring to fasten the support bar to the nut.

Preferably, a clip groove adapted to the clip for restricting the mounting position of the clip is provided on the outer side of each of the support bars.

Preferably, the fixing part is annular, a movable transverse end with elasticity is formed by the transverse slotting of the top half circle and the longitudinal slotting of the tail end of the fixing part, and the movable transverse end and the adjacent fixing end are locked by the cooperation of a latch.

Preferably, the latch teeth of the movable transverse end and the fixed end are respectively arranged inwards and outwards, and the inwards latch teeth of the movable transverse end are matched with the outwards latch teeth of the fixed end; or the movable transverse tail end and the fixed tail end are both arranged up and down, the first latch of the movable transverse tail end comprises two latch parts which are arranged in a back-to-back mode, the second latch of the fixed tail end comprises two latch parts which are arranged in a back-to-back mode, and the first latch is matched with the second latch.

Preferably, the fixing part comprises two semi-annular parts, a gap is reserved between side end parts of the two semi-annular parts, the bottom ends of two side end parts of each semi-annular part are provided with outwards protruding buckling clamping pieces, and the adjacent buckling clamping pieces of the two semi-annular parts are buckled and fixed through buckling fasteners.

Preferably, the inner wall of the fixing part is provided with a stop structure for preventing the nut fixedly connecting assembly from sliding relative to the nut.

Preferably, the monitoring module includes a circuit board fixed to the housing, a monitoring element mounted on the circuit board, and a connector electrically connected to the circuit board.

Preferably, the connector comprises a male head and a female head which are mutually matched and are used for being directly connected in series with an adjacent bolt loosening angle sensor; the monitoring module further comprises two cables, and the two ends of the two cables are respectively connected with the male connector or the female connector of the connector to the circuit board; the shell is equipped with first cable recess, second cable recess respectively with the apron meet the surface, and first cable recess, second cable recess are equipped with first clamping portion, the second clamping portion that is used for blocking the cable jacket respectively.

Preferably, the connector comprises two board-mounted connectors, the two board-mounted connectors are mounted on the circuit board, and the shell is correspondingly provided with mounting grooves for exposing the board-mounted connectors.

Preferably, the upper surface of the shell is provided with a circuit board groove matched with the circuit board, and the cover plate is covered on the upper surface of the shell to form a cavity for fixing the monitoring module; or the lower surface of the shell is provided with a circuit board groove matched with the circuit board, and the cover plate is covered on the lower surface of the shell to form a cavity for fixing the monitoring module.

Preferably, the cover plate is fixed by a screw or a buckle or a combination of a screw and a buckle.

Preferably, two ends of the circuit board are respectively provided with a lug, and the circuit board groove is provided with a side groove corresponding to the lug; each lug is provided with a screw mounting through hole respectively, and the shell is provided with a screw hole corresponding to the screw mounting through hole so as to be screwed in the screw hole through the screw penetrating through the screw mounting through hole.

Preferably, a notch serving as a direction mark is formed on one side of the circuit board.

Preferably, the cavity is filled with insulating glue for packaging the monitoring module.

Preferably, the monitoring element is a TMR sensitive chip capable of converting the sensed magnetic field direction into a resistance value.

Preferably, the circuit board further comprises a single chip microcomputer module, and sensor identity information is stored in the single chip microcomputer module.

Preferably, the monitoring module further comprises an indicator lamp and a zero setting device, wherein the indicator lamp is arranged on the circuit board and used for displaying the working state of the sensor, the zero setting device is used for carrying out initial angle signal zero setting on the sensor, and the indicator lamp and the zero setting device are exposed out of the shell; the cover plate is provided with a plurality of device through holes, and the device through holes are respectively corresponding to the zero device and the indicator lamp, so that the zero device and the indicator lamp are exposed, and a glue filling channel is provided.

Compared with the prior art, the bolt loosening angle sensor has the advantages that the bipolar magnet is arranged on the screw rod fixedly-connected component, the monitoring module for monitoring the magnetic field direction change of the bipolar magnet is arranged on the nut fixedly-connected component, the loosening angle between the screw rod fixedly-connected component and the nut fixedly-connected component is monitored by monitoring the magnetic field direction change of the bipolar magnet, the testing precision is high, the installation is simple, the maintenance is convenient and fast, the cost can be effectively reduced, and the loosening bolt position can be rapidly positioned.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings may be obtained according to the drawings without inventive effort to those skilled in the art.

FIG. 1 is an exploded perspective view of a bolt loosening angle sensor according to an embodiment of the present utility model;

FIG. 2 is a cross-sectional view of the bolt loosening angle sensor of FIG. 1;

FIG. 3 is a cross-sectional view of the bolt loosening angle sensor and the screw nut of FIG. 1 in use;

FIG. 4 is a cross-sectional view of a screw attachment assembly of the bolt loosening angle sensor of FIG. 1;

FIG. 5 is a perspective view of a base of the screw attachment assembly of FIG. 4;

FIG. 6 is a bottom view of the base of FIG. 5;

FIG. 7 is a top view of the base of FIG. 5;

FIG. 8 is a cross-sectional view of the base of FIG. 5;

FIG. 9 is a top view of another embodiment of a screw attachment assembly of the bolt loosening angle sensor of FIG. 1;

FIG. 10 is a cross-sectional view of the screw attachment assembly of FIG. 9;

FIG. 11 is a perspective view of a circuit board of a nut-securing assembly of the bolt-loosening angle sensor of FIG. 1;

FIG. 12 is a perspective view of a housing of the nut-securing assembly of the bolt-loosening angle sensor of FIG. 1;

FIG. 13 is another perspective view of the housing of FIG. 12;

FIG. 14 is a perspective view of a second embodiment of a housing of a nut-securing assembly of the bolt-loosening angle sensor of FIG. 1;

FIG. 15 is a perspective view of a third embodiment of a housing of a nut-securing assembly of the bolt-loosening angle sensor of FIG. 1;

FIG. 16 is a perspective view of a fourth embodiment of a housing of a nut-securing assembly of the bolt-loosening angle sensor of FIG. 1;

FIG. 17 is a perspective view of a cover plate of the nut-securing assembly of the bolt-loosening angle sensor of FIG. 1;

FIG. 18 is an exploded perspective view of a second embodiment of a nut-securing assembly of the bolt-loosening angle sensor of FIG. 1;

FIG. 19 is a perspective assembly view of the nut stem assembly of FIG. 18;

FIG. 20 is an exploded perspective view of a third embodiment of a nut-securing assembly of the bolt-loosening angle sensor of FIG. 1;

FIG. 21 is an exploded perspective view of a fourth embodiment of a nut-securing assembly of the bolt loosening angle sensor of FIG. 1;

FIG. 22 is a perspective assembly view of the nut stem assembly of FIG. 21;

Fig. 23 is a perspective view of another angle of the nut runner assembly of fig. 21.

Detailed Description

In order to enable those skilled in the art to better understand the technical solutions of the present application, the technical solutions of the embodiments of the present application will be clearly and completely described below, and it is obvious that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or be indirectly on the other element; when an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are merely for convenience in describing and simplifying the description based on the orientation or positional relationship shown in the drawings, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" or "a number" means two or more, unless specifically defined otherwise.

It should be understood that the structures, proportions, sizes, etc. shown in the drawings are for illustration purposes only and should not be construed as limiting the application to the extent that it can be practiced, since modifications, changes in the proportions, or adjustments of the sizes, which are otherwise, used in the practice of the application, are included in the spirit and scope of the application which is otherwise, without departing from the spirit or scope thereof.

As shown in the figure, the embodiment of the utility model provides a bolt loosening angle sensor which is used for monitoring the relative loosening condition between a screw rod and a nut, and particularly can be arranged on a plurality of bolts in a high-strength connecting bolt loosening fault easily-occurring area of a wind turbine generator. The bolt loosening angle sensor comprises a screw rod fixedly connected component 1 and a nut fixedly connected component 2.

As shown in fig. 3 to 8, the screw fixing assembly 1 is used for fixing to the screw 3, and includes a base 11 and a bipolar magnet fixed to the base 11.

The bipolar magnet has a pole N and S, and is a bipolar pole 12 having a cylindrical shape in this embodiment.

The base 11 includes a circular base plate 111 and a circular base sidewall 112 formed by extending downward from the periphery of the base plate 111. The bottom plate 111 has a fastening structure (not shown) on its lower surface, which is adapted to the bipolar magnetic pole 12, and a third set of magnetic field markers 1111 located at both ends of the bipolar magnetic pole 12. The clamping structure is used for fixing the bipolar magnetic column 12 on the base 11, and the axial direction of the bipolar magnetic column 12 is kept perpendicular to the axis of the base 11. When the bipolar magnetic pole 12 is installed, the axial direction of the bipolar magnetic pole 12 is adjusted to be vertical to the axis of the base, and structural adhesive is coated at the joint of the buckling structure of the bipolar magnetic pole 12 and the base 11 for reinforcement. The third set of magnetic field marks 1111 are in the form of "N" or "S" and are used for accurately mounting the bipolar magnetic pole 12, and are located on the base 11 and are separately located at two ends of the bipolar magnetic pole 12.

In this embodiment, the fastening structure includes four fastening posts 1112 disposed on the lower surface of the base plate 111. The bipolar magnetic posts 12 are clamped between the four snap posts 1112. The ends of each buckling column 1112 are provided with guide chamfers to facilitate the buckling of the bipolar magnetic column 12. Because the bipolar magnetic pole 12 is fixed to the lower surface of the base plate 111 (i.e., the side facing the screw) by a snap-fit structure, structural adhesive may be applied to the screw prior to assembly. Thus, a closed space is formed, and the bipolar magnetic column is insulated from air and is not easy to rust. In other embodiments, the fastening structure may have other shapes, as shown in fig. 9 and 10, and the fastening structure includes two fastening members 1113 forming an arc-shaped fastening structure, and the bipolar magnetic pillar 12 is pressed and fixed between the two fastening members 1113. The two fastening members 1113 are located on the upper surface of the bottom plate, and the lower edge of the side wall is provided with a protruding structure 1114 for being fastened with the screw rod. The ends of each fastener 1113 are provided with guide chamfers to facilitate the insertion of the bipolar magnet post 12. The bottom plate adopts the fretwork design all around to lighten weight.

The periphery of the base side wall 112 is provided with a first group of magnetic field marks 1121 corresponding to the magnetic poles of the bipolar magnetic column 12, the first group of magnetic field marks 1121 are pentagonal grooves with directional arrows and are provided with an N or S shape, the directions of the magnetic fields are marked by means of the directions of the arrows, and meanwhile, the marking structure can be used as a base to be installed and detached to provide clamping positions. The bottom of the base side wall 112 is provided with an internal thread 1122, the cut-off position of the internal thread 1122 is flush with the top of the buckle structure, and the distance from the end face of the high-strength connecting bolt screw 3 to the top of the base after installation is consistent, so that the consistency of the influence of the screw 3 on the magnetic field is ensured.

As shown in fig. 1 to 3, the nut fixing assembly 2 is used for fixing to a nut 4, and mainly includes a housing 21 and a monitoring module (not shown). The monitoring module is fixed on the shell 21 and is used for monitoring the magnetic field direction change of the bipolar magnet so as to monitor the loosening angle between the screw fixing component 1 and the nut fixing component 2 by monitoring the magnetic field direction change of the bipolar magnet.

The monitoring module comprises a circuit board 22, a monitoring element (not shown), a connector (not shown), a cable 25, two indicator lights 26 and a zero device 27. The monitoring element, the two cables 25, the indicator lights 26 and the zero setting device 27 are arranged on the circuit board 22. The monitoring element is the main element for monitoring the magnetic field variation. Two indicator lights 26 are used to indicate the operating status of the sensor. The zeroing device 27 is used for zeroing the sensor for initial angle signals. As shown in fig. 11, in the present embodiment, the circuit board 22 has a circular plate shape with two symmetrical lugs, and screw mounting through holes 221 are respectively provided on the two lugs. The circuit board 22 also has a notch 222 on one side for use as a direction indicator. One end of the middle part of the circuit board 22 is provided with a device interface 223 for welding the indicator lamp 26 and the zero device 27, and two sides are provided with cable interfaces 224 for welding the cable 25.

In this embodiment, the monitoring element is a TMR (Tunnel MAGNET RESISTANCE) sensitive chip, which converts the sensed magnetic field direction into a resistance value. The sensor main body is fixed on the bolt through the nut fixedly connected part, the other part is a magnet installation component, the sensor main body is driven to rotate through the screw rod fixedly connected part when the bolt rotates, the PCB board containing the TMR sensitive chip is also rotated along with the rotation, the magnet is fixed on the screw rod and does not rotate, the TMR sensitive chip and the magnet rotate relatively in the horizontal direction, the magnetic field direction monitored by the TMR sensitive chip changes, and therefore the loosening angle of the bolt is monitored.

The circuit board can also be provided with a communication unit (such as 485 circuit), a power supply circuit, a power supply control circuit and a singlechip module, and the circuits/elements are electrically connected through the circuit. The single chip microcomputer module can store sensor identity information, and each sensor can be remotely monitored by the communication unit so as to rapidly position the loose bolt.

The connector is connected to the monitoring element by a circuit board 22 to power the monitoring element and transmit signals. In this embodiment, the connector includes a male head 241 and a female head 242 that are mutually matched, and may be a six-core waterproof connector. The two ends of the two cables 25 respectively connect the male 241 and the female 242 of the connector to the circuit board 22, so that the male 241 and the female 242 are connected to the circuit board 22 through the cables 25. Therefore, when adjacent sensors are required to be connected in series, the male head of one sensor is directly connected with the female head of the adjacent sensor in an inserting mode. In other embodiments, the connector may also be mounted directly to the circuit board. As shown in fig. 20, in other embodiments, the on-board connector 243 may be directly welded and fixed on the circuit board 22', and the mounting groove 2111' is provided in the housing 211' to expose the on-board connector 243, so that signal output can be achieved without using a cable, and sealing and waterproofing of the circuit board are easier to achieve. The board-mounted connector 243 may be two identical five-pin connector female sockets, and the cover plate 212' is used to assist in fixing the board-mounted connector by screw connection or snap connection. The board-mounted connector is not limited in shape, but is preferably rectangular or circular. Therefore, when adjacent sensors need to be connected in series, a cable with a connector male head at two ends can be inserted into the connector female seat.

The housing 21 includes a housing 211 and a cover 212 that cooperate to form a cavity with the housing 211 and the cover 212 to secure and encapsulate the monitoring module in the cavity. The cavity is filled with insulating glue for packaging the monitoring module after assembly.

The housing 211 is mainly used as a housing package for the sensor, protecting the internal components. As shown in fig. 12 and 13, in the present embodiment, the housing 211 includes a top plate 2111 and a fixing portion (not shown) formed by the top plate 2111 extending downward for fixing to the nut 4.

The top plate 2111 has a board groove 2112 in the middle of its upper surface for receiving the circuit board 22 to avoid components on the circuit board. The circuit board groove is provided with a side groove corresponding to the lug of the circuit board. Two screw mounting interfaces 2113 are provided in the circuit board recess 2112, and the screw mounting interfaces 2113 may be blind or threaded holes to secure the circuit board 22 in the circuit board recess 2112 by screws 28 through screw mounting through holes 221 in the circuit board. The two sides of the upper surface of the top plate 2111 are respectively provided with a first cable groove 2114 penetrating through the circuit board groove and the outside, the size of the middle part of the first cable groove 2114 is smaller than that of the two sides to form a first clamping part 2115 so as to clamp the cable 25 by the middle part after installation, and if a gap exists between the first cable groove 2114 and the cable 25 between the first clamping part 2115 and the outside, the gap can be covered by coating structural adhesive. Four snap grooves 2116 are provided at the upper peripheral edge of the top plate 2111 for snap-fitting with the cover plate 212. The periphery of the top plate 2111 is also provided with a second set of magnetic field identifiers 2117 corresponding to the first set of magnetic field identifiers 1121.

In this embodiment, the fixing portion includes six support bars 2118, and the ends of the support bars 2118 are fixed to the nut 4 by the clip 29. The support bar 2118 is provided with a serrated protrusion 2119 on the inside thereof as a stop for increasing friction between the nut securing assembly and the nut during installation, preventing the nut securing assembly from sliding relative to the nut. The serrations may also be provided in other shapes such as waves, bars, blocks, etc. that prevent relative sliding of the nut securing assembly. The support bar 2118 outside is provided with the clamp recess 21181 with the clamp adaptation, restricts clamp 29 mounted position, receives external force influence after preventing that clamp 29 from installing and drops, guarantees that the clamp installation back nut links firmly the subassembly and the nut combines the position atress even, has reduced the nut and has linked firmly the space dimension after the subassembly is installed. The clamp comprises a clamping ring which is used for encircling the outer edge of the supporting strip and a clamping piece which is used for tightly adjusting the clamping ring to enable the supporting strip to be fastened on the nut.

In other embodiments, the fixing portion may have other shapes. As shown in fig. 14 and 15, the fixing portion is in a ring shape, the first half circle of the fixing portion is connected with the top plate, the second half circle is transversely slotted, and the tail end of the second half circle is longitudinally slotted to enable the second half circle to have elasticity, and the tail end of the longitudinal slot forms a movable transverse tail end. The movable transverse end and the adjacent fixed end are locked by the latch in a matching way. In the embodiment shown in fig. 14, the latch is disposed on the inner and outer sides of the fixed portion, that is, the latch of the movable transverse end and the latch of the fixed end are disposed inward and outward, respectively, and the inward latch of the movable transverse end mates with the outward latch 2118' of the fixed end. In the embodiment shown in fig. 15, the latch is disposed on the upper and lower sides of the fixing portion, that is, the movable transverse end and the latch of the fixing end are disposed up and down, the first latch 2118″ of the movable transverse end includes two latch portions disposed opposite to each other, the second latch 2119″ of the fixing end includes two latch portions disposed opposite to each other, and the first latch 2118″ of the movable transverse end is engaged with the second latch 2119″ of the fixing end. As shown in fig. 16, the fixing portion may further include two semi-annular portions 2118 '", a gap is formed between two semi-annular portion side end portions 2118'", the bottom ends of two side end portions of each semi-annular portion 2118 '"are provided with outwardly protruding fastening clips 21181'", and two adjacent fastening clips 21181 '"of the semi-annular portions are fastened and fixed by fastening fasteners 2119'".

As shown in fig. 17, in the present embodiment, the cover 212 has a substantially circular plate shape, and four fastening protrusions 2121 are formed on the lower surface of the cover to cooperate with the fastening grooves 2116 of the housing to fasten the cover 212 to the housing 211. The lower surface of the cover plate 212 is provided with two second cable grooves 2122 corresponding to the first cable grooves 2114, the middle part of the second cable grooves 2122 is smaller than the two sides to form a second clamping part 2123, so that the cable 25 is clamped by the middle part after installation, and if a gap exists between the second cable grooves 2122 and the cable 25 between the second clamping part 2123 and the outside, the gap can be covered by coating structural adhesive. The cover 212 is further provided with a first device through hole 2124 and two second device through holes 2125, which respectively correspond to the zero device 27 and the two indicator lamps 26, so that the zero device 27 and the two indicator lamps 26 are exposed, and a glue filling channel is provided. The second device through hole 2125 may be chamfered to accommodate the shape of the indicator light. In other embodiments, as shown in fig. 21 to 23, the circuit board groove 2112 '"may be disposed inside the housing 211'", the first device through hole 2124 '"and the two second device through holes 2125'" are disposed on the upper surface of the housing 211 '"and exposed, the cover 212'" is disposed inside the housing 211 '"and the screws 213'" are used for fixing the circuit board and the cover.

In other embodiments, the housing and the cover plate may be fixed by other methods, as shown in fig. 18 and 19, the housing 211 "and the cover plate 212" may be fixed by screws, the housing is provided with threaded holes, and the cover plate is provided with countersunk holes, and the countersunk screws 213 "are used for fixing. In addition, a combination mode of buckles and screws can be used, so that the connection strength is enhanced, and the cover plate falling off possibly caused by loosening of the screws can be prevented.

In the embodiment, the shell, the cover plate, the base and the male/female connector are made of weather-resistant engineering plastics, the bolts and the clamp are made of stainless steel, the bipolar magnetic columns are made of permanent magnet materials, and the bipolar magnetic columns are integrally assembled together, so that the sensor has good toughness. The stainless steel clamp, the plastic shell and the high-strength structural steel nut are matched, the stress of the shell is uniform, and the connection reliability between the shell and the nut can be ensured.

The assembly process of the screw rod fixedly connected component comprises the following steps: the bipolar magnet is fastened and fixed on the base.

The assembly process of the nut fastening assembly is described as follows:

The circuit board is horizontally placed in a circuit board groove arranged in the shell, and two screws are screwed into the shell along screw mounting through holes arranged on the circuit board, so that the circuit board and the shell are fixedly connected;

Welding and fixing the cable at a corresponding welding position of the circuit board, coating structural adhesive in a cable groove formed in the shell, and placing the cable in the cable groove to limit the cable;

Coating structural adhesive on the upper surface of the shell (the surface contacted with the cover plate), and pressing the buckling protrusion of the cover plate into the buckling groove of the shell in an aligned manner to realize the fixed connection between the shell and the cover plate and the cable fixation;

filling sealant through a device through hole arranged on the cover plate, and fully covering the welding positions of the circuit board and the cable to realize the sealing and insulation of the sensor;

the male and female heads of the connector are respectively arranged at two ends of the cable;

The clamp is installed in a clamp groove formed in the shell, and the clamp is screwed down to keep falling off after the clamp is installed on the nut.

The installation process of the bolt loosening angle sensor and the bolt is as follows:

The screw rod fixing component is screwed and fixed on the screw rod;

The nut fixedly connecting assembly is fixed on the nut from the upper part of the screw fixedly connecting assembly, and the shell supporting piece is fastened on the outer edge of the nut through the clamp. After installation, the base and the shell are spaced in the axial direction of the screw rod, so that the base and the shell are prevented from being abutted against each other after the bolts are loosened, mutual friction is formed, and the base or the shell is caused to shift to influence the monitoring effect of the sensor.

Compared with the prior art, the bolt loosening angle sensor has the following advantages: the sensor has high test precision, simple installation and convenient maintenance, can effectively reduce cost and can rapidly position the loose bolt. The sensor is provided with two complementary connectors, meets the loosening detection requirement of the high-strength connecting bolt group of the annularly distributed wind turbine tower or hub, and reduces the wiring length. The sensor is divided into two components, and for loose high-strength connecting bolt maintenance, when the condition that a bolt is loose is found through monitoring of the sensor, the loose bolt can be screwed only by disassembling the nut fixing component installed on the loose nut. After the sensor is screwed, the nut fixing component of the sensor can be fixed on the nut again, and the monitoring of the loosening condition of the bolt is continued, so that the sensor can be used for a second time. The sensor exposes the pilot lamp and the zero setting device, the working state of the sensor can be judged through the pilot lamp, and the initial angle signal zero setting is carried out on the reinstalled sensor through the zero setting device. The sensor can adapt to the limited bolt group in installation space, to a plurality of sensors that link up in series, the whereabouts of single sensor receive the cable constraint, and the sensor can not cause great influence to wind turbine generator system, and the security is higher. The sensor is mainly made of plastic materials, can withstand severe environmental humidity and salt fog, ensures that the sensor works stably in various environments, and has a long service life.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present utility model. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the utility model. Thus, the present utility model is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (27)

1. The bolt loosening angle sensor is used for monitoring the relative loosening condition between a screw and a nut and is characterized by comprising a screw fixing component and a nut fixing component; the screw rod fixing component is used for being fixed on the screw rod and comprises a base and a bipolar magnet, and the bipolar magnet is fixed on the base; the nut fixedly connected assembly is used for being fixed on the nut and comprises a shell and a monitoring module, wherein the monitoring module is fixed on the shell and used for monitoring the magnetic field direction change of the bipolar magnet so as to monitor the loosening angle between the screw fixedly connected assembly and the nut fixedly connected assembly through monitoring the magnetic field direction change of the bipolar magnet.

2. The bolt looseness angle sensor of claim 1, wherein the bipolar magnet is a bipolar magnetic column, the base comprises a bottom plate and a clamping structure which is positioned on the bottom plate and matched with the bipolar magnetic column, the bipolar magnetic column is fixed on the base through the clamping structure, and the axial direction of the bipolar magnetic column is kept perpendicular to the axis of the base.

3. The bolt looseness angle sensor of claim 2, wherein the snap structure comprises four snap posts, the bipolar magnetic posts being clamped between the four snap posts; or the buckling structure comprises two buckling pieces forming an arc-shaped enclasping structure, and the bipolar magnetic column is pressed and fixed between the two buckling pieces.

4. A bolt loosening angle sensor as claimed in claim 3, wherein the catch formation is located on a side of the base floor facing the screw or on a side remote from the screw.

5. The bolt loosening angle sensor as claimed in claim 1, comprising a first set of magnetic field markers each corresponding to a bipolar magnet pole, the first set of magnetic field markers being located at a periphery of the base;

and/or a second set of magnetic field signatures, the second set of magnetic field signatures being located at the perimeter of the housing;

And/or a third group of magnetic field marks, wherein the third group of magnetic field marks are positioned on the base and are respectively arranged at two ends of the bipolar magnet.

6. The bolt looseness angle sensor of claim 1, wherein the base is fixed to the screw by a threaded connection or a snap-fit.

7. The bolt looseness angle sensor of claim 1, wherein the base is spaced from the housing in the axial direction of the screw to avoid abutment of the base with the housing after looseness of the bolt.

8. The bolt looseness angle sensor of claim 1, wherein the housing includes a mating housing and cover plate, the housing and cover plate forming a cavity to secure and encapsulate the monitoring module in the cavity.

9. The bolt looseness angle sensor of claim 8, wherein the housing includes a top plate and a fixing portion formed by the top plate extending downward to be fixed to the nut.

10. The bolt loosening angle sensor of claim 9, wherein the fixing portion comprises a plurality of support bars, and the ends of the support bars are fixed to the nut by clips.

11. The bolt looseness angle sensor of claim 10, wherein the clip comprises a snap ring for encircling the outer edge of the support bar and a clamp for tightening the snap ring to secure the support bar to the nut.

12. The bolt loosening angle sensor of claim 11, wherein each of the support bars is provided on an outer side with a clip groove adapted to the clip to limit a mounting position of the clip.

13. The bolt loosening angle sensor as claimed in claim 9, wherein the fixing portion is in a ring shape, and the movable transverse end having elasticity is formed by a top half-turn transverse slit and a distal end longitudinal slit thereof, and is locked with the adjacent fixing end by a latch fit.

14. The bolt looseness angle sensor of claim 13, wherein the movable transverse end and fixed end latches are disposed inwardly and outwardly, respectively, and the movable transverse end inwardly facing latches mate with fixed end outwardly facing latches; or the movable transverse tail end and the fixed tail end are both arranged up and down, the first latch of the movable transverse tail end comprises two latch parts which are arranged in a back-to-back mode, the second latch of the fixed tail end comprises two latch parts which are arranged in a back-to-back mode, and the first latch is matched with the second latch.

15. The bolt loosening angle sensor as claimed in claim 9, wherein the fixing portion includes two semi-annular portions, a gap is provided between side ends of the two semi-annular portions, the bottom ends of both side ends of each semi-annular portion are provided with outwardly protruding snap fasteners, and adjacent snap fasteners of the two semi-annular portions are fastened and fixed by the snap fasteners.

16. The bolt looseness angle sensor of claim 9, wherein the fixed portion inner wall is provided with a stop structure preventing the nut-securing assembly from sliding relative to the nut.

17. The bolt looseness angle sensor of claim 8, wherein the monitoring module comprises a circuit board secured to the housing, a monitoring element mounted on the circuit board, and a connector electrically connected to the circuit board.

18. The bolt looseness angle sensor of claim 17, wherein the connector comprises a male head and a female head that are mutually adapted for direct tandem connection with an adjacent bolt looseness angle sensor; the monitoring module further comprises two cables, and the two ends of the two cables are respectively connected with the male connector or the female connector of the connector to the circuit board; the shell is equipped with first cable recess, second cable recess respectively with the apron meet the surface, and first cable recess, second cable recess are equipped with first clamping portion, the second clamping portion that is used for blocking the cable jacket respectively.

19. The bolt looseness angle sensor of claim 17, wherein the connector comprises two board connectors mounted on a circuit board, and the housing is correspondingly provided with mounting slots for exposing the board connectors.

20. The bolt looseness angle sensor of claim 17, wherein the upper surface of the housing is provided with a circuit board groove matched with the circuit board, and the cover plate covers the upper surface of the housing to form a cavity for fixing the monitoring module; or the lower surface of the shell is provided with a circuit board groove matched with the circuit board, and the cover plate is covered on the lower surface of the shell to form a cavity for fixing the monitoring module.

21. The bolt looseness angle sensor of claim 20, wherein the cover plate is fixed by screws or snaps or a combination of screws plus snaps.

22. The bolt looseness angle sensor of claim 20, wherein the two ends of the circuit board are respectively provided with lugs, and the circuit board groove is provided with side grooves corresponding to the lugs; each lug is provided with a screw mounting through hole respectively, and the shell is provided with a screw hole corresponding to the screw mounting through hole so as to be screwed in the screw hole through the screw penetrating through the screw mounting through hole.

23. The bolt loosening angle sensor as claimed in claim 17, wherein one side of the circuit board is provided with a notch as a direction indicator.

24. The bolt looseness angle sensor of claim 17 in which the cavity is filled with an insulating gel for encapsulating the monitoring module.

25. The bolt looseness angle sensor of claim 17, wherein the monitoring element is a TMR sensitive chip capable of converting a sensed magnetic field direction into a resistance value.

26. The bolt looseness angle sensor of claim 17, wherein the circuit board further comprises a single-chip microcomputer module, and wherein the single-chip microcomputer module stores sensor identity information.

27. The bolt looseness angle sensor of claim 17, wherein the monitoring module further comprises an indicator light mounted on the circuit board for displaying the working state of the sensor and a zero device for zeroing the sensor initial angle signal, the indicator light and the zero device being exposed to the housing; the cover plate is provided with a plurality of device through holes, and the device through holes are respectively corresponding to the zero device and the indicator lamp, so that the zero device and the indicator lamp are exposed, and a glue filling channel is provided.