CN214384521U - Magnetic force excitation bolted joint vibration failure experimental apparatus - Google Patents

Abstract

The utility model discloses a magnetic force excitation bolted joint vibration failure experimental device, which comprises a supporting base, an excitation device, a testing device and an acquisition and analysis device; the excitation device can drive the moving magnet to operate by the driving motor and generate periodic magnetic force to act on the tested bolt so as to enable the bolt joint to generate vibration failure; displacement, acceleration and strain sensors on the testing device can respectively obtain three response signals of displacement, acceleration and strain of the bolt joint; the acquisition and analysis device can research various failure conditions such as screw loosening, slippage of a connected piece, vibration fatigue and the like of the bolt joint through analyzing the obtained response signals. The utility model discloses a reasonable design has simulated various vibration excitations in the engineering effectively, has increased the variety of experiment and has compared the vibration inefficacy experiment effect of different connected modes through accurately controlling various variables, has important value to the research in aspects such as bolted joint vibration inefficacy dynamics reliability.

Description

Magnetic force excitation bolted joint vibration failure experimental apparatus

Technical Field

The utility model belongs to the technical field of mechanical vibration and equipment test, concretely relates to magnetic force excitation bolted joint vibration failure experimental apparatus.

Background

The bolt connecting structure is widely applied to various mechanical equipment and connecting fields due to the advantages of simple structure, convenience in disassembly and assembly, low cost and the like. With the development of modern mechanical equipment towards high speed, high temperature and high pressure, the bolt joints of most mechanical devices are inevitably subjected to vibration load, and even various vibration failures such as bolt loosening, slippage of connected parts, vibration fatigue and the like of a bolt connecting structure can be caused, so that the reliability of the bolt joints is seriously challenged.

The single lap joint and the double lap joint are two important assembling forms of bolt connection, and the force borne by the two important assembling forms is shearing force, so that under the action of vibration load, the number and the layout of the bolts, the gap between the bolts and holes, the pretightening force and the like can greatly influence the reliability of the bolt joint.

Researchers have now conducted extensive research around bolted joint vibration failure. In the research of failure forms, most research schemes only focus on a single failure form, and in practical application, most of the failures of the bolt joints are the result of mutual coupling of a plurality of failure forms instead of one failure form due to the fact that mechanical equipment is in a complicated and varied working environment; in the selection of the excitation mode, the excitation mode for the bolt joint vibration failure reliability test is almost a contact loading mode, and the contact loading mode not only can enable the vibration excitation device to be in direct contact with the tested object, but also can change the physical property and the stress mode of the tested object, so that the accuracy of the boundary condition cannot be controlled; in the study of the assembly form, the existing experimental device can only study one assembly form, and when the assembly form is changed, the stress environment of the bolt joint can be changed, so that the comparison experiment of different assembly forms of the bolt connecting structure cannot be carried out.

Therefore, the magnetic force excitation bolt joint vibration failure experimental device and the test method provided by the invention utilize non-contact magnetic force as the excitation force for applying vibration load, and simultaneously test multiple vibration failures of single and double-lap joint bolt connection structures in two different assembly forms, thereby having important application value for promoting the dynamic research progress of the vibration reliability of the bolt joint.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a can test simultaneously single, two overlap joint bolted joint multiple vibration inefficacy experimental apparatus under non-contact magnetic force excitation to study bolted joint vibration inefficacy problem under different environment.

In order to solve the technical problem, the utility model provides a magnetic force excitation bolted joint vibration failure experimental apparatus, which comprises a supporting base, an excitation device, a testing device and an acquisition and analysis device; the excitation device comprises a driving motor, a rotating disk and a movable magnet, the driving motor is arranged on one side of the middle part of the supporting base, the output end of the driving motor is connected with the rotating disk, a plurality of movable magnets are uniformly distributed on the rotating disk in the circumferential direction, and the N poles or the S poles of the plurality of movable magnets face outwards; a single-lap-joint bolt joint supporting seat and a double-lap-joint bolt joint supporting seat are respectively arranged at two ends of the supporting base; the testing device comprises a single lap-joint bolt joint connecting plate, a double lap-joint bolt joint connecting plate, a displacement sensor, a strain sensor, an acceleration sensor, a first fixed magnet and a second fixed magnet, wherein the single lap-joint bolt joint connecting plate is slidably arranged on the single lap-joint bolt joint supporting seat, the double lap-joint bolt joint connecting plate is detachably arranged on the double lap-joint bolt joint supporting seat, the first fixed magnet and the second fixed magnet are respectively and fixedly arranged at one ends, close to the rotating disc, of the single lap-joint bolt joint connecting plate and the double lap-joint bolt joint connecting plate, the displacement sensor and the acceleration sensor are respectively arranged on the single lap-joint bolt joint connecting plate and the double lap-joint bolt joint connecting plate, a plurality of thread through holes are respectively and correspondingly arranged on the single lap-joint bolt joint supporting seat, the double lap-joint bolt joint connecting plate and the double lap-joint bolt joint supporting seat, the threaded through holes are matched with the tested bolts, and the tested bolts are provided with the strain sensors; the acquisition and analysis device is respectively electrically connected with the displacement sensor, the strain sensor and the acceleration sensor.

The utility model discloses an adopt above technical scheme, usable driving motor drive rotary disk is rotatory, and it is rotatory in order to form rotating magnetic field to drive a plurality of moving magnets on the rotary disk, utilize repulsion force or appeal between moving magnet and fixed magnet simultaneously, provide and await measuring bolt non-contact's exciting force, utilize this exciting force can study the bolt that awaits measuring because of the screw thread that the vibration produced is not hard up, by multiple failure modes such as connecting piece slip and vibration fatigue, and can study the vibration failure mode of the bolt that awaits measuring under the different assembly modes simultaneously.

Furthermore, the N pole or the S pole of the first fixed magnet and the second fixed magnet is opposite to the N pole or the S pole of the movable magnet, so that attractive force or repulsive force can be generated between the first fixed magnet and the movable magnet and between the second fixed magnet and the movable magnet, namely the vibration excitation device can generate certain excitation force on the bolt to be tested.

Furthermore, 2-8 movable magnets are arranged, so that the vibration excitation frequency of the vibration excitation device on the bolt to be tested can be changed, namely the vibration frequency of the bolt to be tested is changed.

Furthermore, the driving motor is set as a speed regulating motor, so that the rotating speed of the rotating disk and the moving magnet can be regulated to change the excitation frequency between the moving magnet and the first fixed magnet and/or the second fixed magnet, namely, the vibration frequency of the bolt to be tested is changed.

Furthermore, the speed regulating motor is electrically connected with the acquisition and analysis device, so that the rotating speed of the speed regulating motor can be automatically regulated and controlled to change the vibration frequency of the bolt to be tested, and the accuracy of the test result of the vibration failure of the magnetic excitation bolt joint can be improved.

Furthermore, the excitation device further comprises a rotating shaft and a bearing seat, the bearing seat is arranged in the middle of the supporting base and is far away from the driving motor, one end of the rotating shaft is connected with the output end of the driving motor, the other end of the rotating shaft is supported on the bearing seat, the rotating disk is fixedly arranged on the rotating shaft and is arranged between the driving motor and the bearing seat, and therefore the excitation device can be stably installed on the supporting base to output stable excitation force.

Furthermore, the rotary disk comprises two rotary bodies and a connecting shaft arranged between the rotary bodies, wherein a plurality of mounting grooves are uniformly distributed in the circumferential direction on one side, opposite to the rotary bodies, of each rotary body correspondingly, the two ends of each movable magnet are correspondingly and respectively fixedly arranged in the mounting grooves, the two ends of each connecting shaft are respectively connected with the centers of the two rotary bodies, and the connecting shafts are fixedly sleeved on the rotary shafts, so that the movable magnets can be stably arranged on the rotary disk.

Furthermore, the bearing seat comprises an L-shaped bearing seat and a T-shaped bearing seat which are fixedly arranged on the supporting base, the L-shaped bearing seat and the T-shaped bearing seat are respectively arranged at two sides of the rotating disc, and the rotating shaft sequentially penetrates through the T-shaped bearing seat, the rotating disc and the L-shaped bearing seat, so that the vibration excitation device can be further stably arranged on the supporting base to output stable vibration excitation force.

Furthermore, a plurality of parallel T-shaped grooves are formed in the middle of the supporting base, and the bottom of the bearing seat is fixedly arranged on the T-shaped grooves through bolts, so that the bearing seat can be stably installed, and the distance between the excitation device and the first fixed magnet and/or the second fixed magnet can be adjusted.

Furthermore, the excitation device further comprises a motor base, the driving motor is fixedly arranged on the motor base, a plurality of motor base mounting holes are correspondingly formed in the supporting base relative to the T-shaped groove, the motor base is fixedly arranged on the supporting base through fixing bolts, and the axial lead of the driving motor is consistent with the axial lead of the bearing hole of the bearing base, so that the distance between the excitation device and the first fixed magnet and/or the second fixed magnet can be adjusted.

Furthermore, a plurality of first threaded through holes are formed in the single lap joint bolt joint support base, and a plurality of second threaded through holes are formed in the double lap joint bolt joint support base; it is a plurality of to correspond on the single overlap joint bolted joint connecting plate first threaded through-hole is equipped with a plurality of third threaded through-holes, it is a plurality of to correspond on the double overlap joint bolted joint connecting plate second threaded through-hole is equipped with a plurality of fourth threaded through-holes, can install the bolt that awaits measuring on single overlap joint bolted joint supporting seat and/or double overlap joint bolted joint supporting seat like this in order to carry out the vibration inefficacy experiment.

Furthermore, a plurality of first threaded through holes are arrayed on the single-lap-joint bolt joint support seat, a plurality of second threaded through holes are arrayed on the double-lap-joint bolt joint support seat, and therefore the bolts to be tested can be arrayed according to actual needs.

Furthermore, the two sides of the single lap joint bolt joint support base are symmetrically and fixedly provided with slide ways, the slide ways are all provided with slide blocks in a sliding mode, and the two sides of the single lap joint bolt joint connection plate are respectively and fixedly arranged on the slide blocks, so that the distance between the first fixed magnet and the excitation device can be adjusted to adjust the excitation force of the excitation device on the bolt to be tested.

Furthermore, the sliding block is electrically connected with the acquisition and analysis device, so that the distance between the first fixed magnet and the excitation device can be automatically regulated and controlled to regulate the excitation force of the excitation device on the bolt to be tested.

Furthermore, the double-lap-joint bolt joint supporting seat comprises a bottom plate and a top plate which are integrally formed, and the double-lap-joint bolt joint connecting plate is detachably arranged between the bottom plate and the top plate, so that the accuracy of a vibration failure test result of the double-lap-joint bolt joint can be improved.

Compared with the prior art, the beneficial effects of the utility model are that:

(1) the driving motor (or the speed regulating motor) can be used for driving the rotating disk and the moving magnet to continuously rotate for a long time so as to generate a rotating magnetic field with controllable speed (or frequency); meanwhile, on the premise of not changing the physical property of the bolt joint, the non-contact magnetic force between the rotating magnetic field and the fixed magnet is used as an exciting force to excite the tested bolt to vibrate.

(2) Three response signals can be obtained by utilizing the strain sensor, the acceleration sensor and the displacement sensor which are linked with the tested bolt, so that the method is used for researching various failure modes of the tested bolt, such as thread loosening, slippage of a connected piece, vibration fatigue and the like, caused by vibration.

(3) The vibration failure experiment of single, two overlap joint bolted joint can be carried out simultaneously to usable single, two overlap joint bolted joint test benches to can carry out the vibration failure experiment under the stress environment such as different bolt overall arrangement, different bolt clearance, different bolt pretightning forces, so that the reliability of bolted joint under different environment of research.

(4) Various vibration excitations in engineering are effectively simulated through reasonable design, experimental diversity is increased through accurately controlling various variables, vibration failure experimental effects of different connection modes are compared, and the method has important value on researches on vibration failure dynamics reliability and the like of the bolt joint.

Drawings

Fig. 1 is a schematic view of the overall structure of a magnetic force excitation bolt joint vibration failure experimental device of the utility model;

FIG. 2 is a schematic structural view of a support base in the magnetic force excitation bolted joint vibration failure experimental apparatus of the present invention;

fig. 3 is a schematic structural view of an excitation device in the magnetic force excitation bolted joint vibration failure experimental apparatus of the present invention;

fig. 4 is a schematic structural view of a single lap joint bolted joint test stand in the magnetic force excitation bolted joint vibration failure experimental apparatus of the present invention;

FIG. 5 is a schematic structural view of a double-lap joint bolted joint test bed in the magnetic force excitation bolted joint vibration failure experimental apparatus of the present invention;

fig. 6 is a schematic distribution diagram of a second tested bolt and a strain sensor in the magnetic force excitation bolted joint vibration failure experimental apparatus of the present invention;

fig. 7 is a schematic distribution diagram of a first tested bolt and a strain sensor in the magnetic force excitation bolted joint vibration failure experimental apparatus of the present invention;

fig. 8 is a test schematic diagram of the magnetic force excitation bolt joint vibration failure experimental apparatus of the present invention;

fig. 9 is a load-displacement curve diagram of the magnetic force excitation bolt joint vibration failure experimental apparatus of the present invention;

fig. 10 is a graph of the stiffness-displacement curve of the magnetic force excitation bolted joint vibration failure experimental apparatus of the present invention;

FIG. 11 is a graph of the load-fatigue cycle times of the magnetic force excitation bolted joint vibration failure experimental apparatus of the present invention;

fig. 12 is a graph of fatigue stiffness-cycle number curve of a magnetic force excitation bolted joint vibration failure experimental apparatus of the present invention;

in the figure: 1-an acceleration sensor, 2-a single lap bolt joint test stand, 3-an excitation device, 4-a support base, 5-a double lap bolt joint test stand, 6-a strain sensor, 7-a displacement sensor, 8-a single lap bolt joint support stand, 9-a motor support stand, 10-a double lap bolt joint support stand, 11-a T-shaped groove, 12-a bearing, 13-an L-shaped bearing stand, 14-a flange plate, 15-a connecting shaft, 16-a T-shaped bearing stand, 17-a speed regulating motor, 18-a motor stand, 19-a coupler, 20-a rotating shaft, 21-a movable magnet, 22-a rotating disc, 23-a slideway, 24-a sliding block, 25-a single lap bolt joint connecting plate, 26-a first bolt to be tested, 27-a first fixed magnet, 28-a double-lap-joint bolt joint connecting plate, 29-a second fixed magnet, 30-a second bolt to be tested, 31-a first threaded through hole, 32-a second threaded through hole, 33-a third threaded through hole, 34-a rotator, 35-a bottom plate, 36-a top plate and 37-a bearing seat fixing bolt.

Detailed Description

The technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiment of the present invention. It is obvious that the described embodiments are only some of the embodiments of the present invention, and not all of them. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top/bottom", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as being right to the present invention

The limit of (2). Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted", "provided", "sleeved/connected", "connected", and the like are to be understood in a broad sense, such as "connected", which may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The single lap-joint bolt joint is used for directly connecting the single lap-joint bolt joint connecting plate with the single lap-joint bolt joint supporting seat; the double-lap-joint bolt joint is used for arranging a double-lap-joint bolt joint connecting plate between the double-lap-joint bolt joint supporting seats. Because single overlap joint bolted joint and two overlap joint bolted joint are more common two kinds of bolted connection types, and the vibration of these two kinds of bolted connection types became invalid and is the focus of present industry research, so the utility model discloses use single overlap joint bolted joint and two overlap joint bolted joint's vibration inefficacy experimental apparatus and test method to explain as the example.

As shown in fig. 1 to 7, it is a schematic structural diagram of the magnetic force excitation bolt joint vibration failure experimental apparatus of the present invention.

As shown in fig. 1, the utility model provides a pair of magnetic force excitation bolted joint vibration failure test device includes support base 1, excitation device 3, single overlap joint bolted joint test bench 2, two overlap joint bolted joint test benches 5 and collection analytical equipment.

Specifically, the excitation device 3 includes a drive motor, a rotary disk 22, and a moving magnet 21. The driving motor is arranged on one side of the middle part of the supporting base 4, the output end of the driving motor is connected with the rotating disc 22, a plurality of moving magnets 21 are uniformly distributed on the rotating disc 22 in the circumferential direction, and the N poles or the S poles of the moving magnets 21 face outwards.

Meanwhile, the two ends of the supporting base 4 are respectively provided with the single-lap-joint bolt joint test bed 2 and the double-lap-joint bolt joint test bed 5.

Wherein, single overlap joint bolted joint test bench 2 includes single overlap joint bolted joint supporting seat 8 and single overlap joint bolted joint testing arrangement. The single lap bolted joint testing device comprises a single lap bolted joint connecting plate 25, a displacement sensor 7, a strain sensor 6, an acceleration sensor 1 and a first fixed magnet 27. The single lap joint bolt joint connecting plate 25 is slidably disposed on the single lap joint bolt joint support base 8, the first fixed magnet 27 is fixedly disposed at one end of the single lap joint bolt joint connecting plate 25 close to the rotating disk 22, and the displacement sensor 7 and the acceleration sensor 1 are disposed on the single lap joint bolt joint connecting plate 25. A plurality of threaded through holes are correspondingly formed in the single lap joint bolt joint connecting plate 25 and the single lap joint bolt joint supporting base 8, the threaded through holes are matched with the first tested bolt 26, and the strain sensor 6 is arranged on the first tested bolt 26 (as shown in fig. 6).

The double lap bolted joint test stand 5 includes a double lap bolted joint support seat 10 and a double lap bolted joint testing device. The double-lap-joint bolt joint testing device comprises a double-lap-joint bolt joint connecting plate 28, a displacement sensor 7, a strain sensor 6 and a second fixed magnet 29 of the acceleration sensor 1. The double lap joint bolt joint connecting plate 28 is detachably disposed on the double lap joint bolt joint support base 10, the second fixed magnet 29 is fixedly disposed at one end of the double lap joint bolt joint connecting plate 28 close to the rotating disk 22, and the displacement sensor 7 and the acceleration sensor 1 are disposed on the double lap joint bolt joint connecting plate 28. A plurality of threaded through holes are correspondingly formed in the double-lap bolted joint connecting plate 28 and the double-lap bolted joint support base 10, the threaded through holes are matched with the second tested bolt 30, and the strain sensor 6 is arranged on the second tested bolt 30.

As shown in fig. 7, the collecting and analyzing device is electrically connected to the displacement sensor 7, the strain sensor 6 and the acceleration sensor 1, respectively. In this embodiment, the collecting and analyzing device includes a data collector electrically connected to the displacement sensor 7 and the acceleration sensor 1, a dynamic strain gauge electrically connected to the strain sensor 6, and a computer system electrically connected to the data collector and the dynamic strain gauge. Wherein, the data acquisition unit can acquire the stress (or load) of the tested bolt through the acceleration sensor 1 to carry out vibration test; the data acquisition unit can also acquire the displacement of the tested bolt through the displacement sensor 7 to carry out the slippage test; the dynamic strain gauge can collect the strain around the hole of the tested bolt through the strain sensor 6 to perform deformation test; the computer system can acquire the acceleration displacement signals and the strain signals acquired by the data acquisition unit and the dynamic strain gauge, perform comprehensive processing, draw and obtain a load-displacement curve and a rigidity-displacement curve, and finally obtain a load-fatigue cycle time curve and a fatigue rigidity-cycle time curve, namely a so-called failure curve.

The utility model discloses it is rotatory that usable driving motor drives the rotary disk, and it is rotatory in order to form rotating magnetic field to drive a plurality of moving magnets on the rotary disk, utilize simultaneously moving magnet and first fixed magnet and/or second fixed magnet repulsion force or appeal between, provide and the excitation force of the bolt non-contact that awaits measuring, then utilize this excitation force can study the bolt that awaits measuring because of the screw thread that the vibration produced is not hard up, by multiple failure modes such as connecting piece slip and vibration fatigue, and can study the vibration failure mode of the bolt that awaits measuring under the different assembly modes simultaneously.

As an embodiment of the present invention, the first fixed magnet 27 and the second fixed magnet 29 may be respectively adhered to the single lap-joint bolt joint connecting plate 25 and the double lap-joint bolt joint connecting plate 28 by using AB glue or metal super glue, and the N poles of the first fixed magnet 27 and the second fixed magnet 29 are both disposed opposite to the N pole of the movable magnet 21, or the S poles of the first fixed magnet 27 and the second fixed magnet 29 are both disposed opposite to the N pole of the movable magnet 21, or the N poles of the first fixed magnet 27 and the second fixed magnet 29 are both disposed opposite to the S pole of the movable magnet 21, or the S poles of the first fixed magnet 27 and the second fixed magnet 29 are both disposed opposite to the S pole of the movable magnet 21, so that an attractive force or a repulsive force may be generated between the first fixed magnet 27 and the movable magnet 21 and between the second fixed magnet 29 and the movable magnet 21, that a certain to-be-excited magnetic bolt 26 and/or a certain to-be-excited magnetic bolt 30 to be excited may be generated by the excitation device 3 Force.

As an embodiment of the present invention, the moving magnet 21 is configured as a magnetic strip, one side of the magnetic strip is N-pole and the other side is S-pole, and the first fixed magnet 27 and the second fixed magnet 29 are also configured as a magnetic strip, and one side of the first fixed magnet 27 and the second fixed magnet 29 is N-pole and the other side is S-pole. In addition, 2 to 8 moving magnets 21 are provided, and the specifications of the plurality of moving magnets 21 are consistent, that is, the magnetic pole directions, the external dimensions and the magnetic field strengths of the plurality of moving magnets 21 are all consistent, so that the excitation frequency of the excitation device 3 to the first bolt to be tested 26 and/or the second bolt to be tested 30, that is, the vibration frequency of the first bolt to be tested 26 and/or the second bolt to be tested 30 can be changed by changing the specifications of the moving magnets 21, so as to simulate various vibration excitations in the engineering, and periodic excitation magnetic forces with different magnitudes can be generated according to actual needs.

As an embodiment of the present invention, the driving motor is set as the adjustable speed motor 17, and this adjustable speed motor 17 can be connected with the computer system electric connection in the collection analysis device, so that the rotational speed of the rotating disk 22 and the moving magnet 21 can be adjusted by the adjustable speed motor 17 to change the excitation frequency between the moving magnet 21 and the first fixed magnet 27 and/or the second fixed magnet 29, i.e. the vibration frequency of the first bolt 26 and/or the second bolt 30 to be tested is changed, and the rotational speed of the adjustable speed motor 17 can be manually/automatically adjusted to change the vibration frequency of the first bolt 26 and/or the second bolt 30 to be tested, and the accuracy of the test result of the magnetic excitation bolt joint vibration failure is improved.

As an embodiment of the present invention, as shown in fig. 2, the supporting base 4 is made of cast iron, and is integrally formed in a rectangular shape. The two ends of the support base 4 are respectively provided with the single-lap-joint bolt joint support base 8 and the double-lap-joint bolt joint support base 10, and the single-lap-joint bolt joint support base 8 and the double-lap-joint bolt joint support base 10 are both arranged into frame shapes with openings at the two ends.

Further, a plurality of first threaded through holes 31 are formed in the center of the top of the single lap joint bolt joint support base 8, and the first threaded through holes 31 are matched with the first bolts 26 to be tested. Preferably, in some embodiments, a plurality of the first threaded through holes 31 are arranged in the central array at the top of the single lap bolt joint supporting seat 8, so that the first bolts 26 to be tested can be arranged according to actual needs to simulate the single lap bolt connection structure in various mechanical equipment.

Furthermore, the top of the double lap bolt joint support base 10 is configured to include a bottom plate 35 and a top plate 36 which are integrally formed, and the bottom plate 35 and the top plate 36 are arranged in parallel to form a double-layer structure; meanwhile, the distance between the bottom plate 35 and the top plate 36 is adapted to the thickness of the double lap bolt joint connection plate 28, so that the double lap bolt joint connection plate 28 is detachably disposed between the bottom plate 35 and the top plate 35, and thus the accuracy of the double lap bolt joint vibration failure test result can be improved.

In addition, a plurality of second screw through holes 32 are formed at the center of the top of the double lap bolt joint support base 10, and the second screw through holes 32 are adapted to the second bolts 30 to be tested. Preferably, in some embodiments, a plurality of second threaded through holes 32 are arranged in a central array at the top of the double lap bolt joint support base 10, so that the second tested bolts 30 can be arranged according to actual needs to simulate the double lap bolt joint structure in various mechanical equipment.

In addition, a plurality of parallel T-shaped grooves 11 are formed in the middle of the support base 4, and the T-shaped grooves 11 can be matched with the bearing seat fixing bolts 37 connected to the bottom of the bearing seat, so that the bearing seat can be stably installed on the support base, and the distance between the bearing seat (or a rotating disk) and the single lap bolt joint support seat 8 and/or the double lap bolt joint support seat 10, that is, the distance between the movable magnet 21 and the first fixed magnet 27 and/or the second fixed magnet 29, can be adjusted.

Finally, a motor support base 9 is arranged on one side of the middle part of the supporting base 4, and the motor support base 9 is also arranged into a frame shape with two open ends. A plurality of motor base mounting holes (not shown) are correspondingly formed in the top of the motor support base 9 corresponding to the T-shaped groove 11, and the motor base mounting holes are matched with fixing bolts on the motor base 18 for bearing the driving motor, so that the driving motor can be fixedly mounted on the motor support base 9 of the support base 4 through the motor base 18, and the axial lead of the driving motor can be kept consistent with the axial lead of a bearing hole of the bearing base by adjusting the positions of the motor base 18 and the bearing base, so that the distance between the movable magnet 21 and the first fixed magnet 27 and/or the second fixed magnet 29 can be adjusted.

As an embodiment of the present invention, as shown in fig. 3, the excitation device 3 includes an adjustable speed motor 17, a motor base 18, a rotating shaft 20, a bearing seat, a rotating disk 22, and a moving magnet 21.

The speed regulating motor 17 is supported on a motor base 18, and the motor base 18 can be fixedly mounted on the motor support base 9 of the support base 4 through a fixing bolt. The output shaft of the speed-regulating motor 17 penetrates through the motor base 18 and is rigidly connected to one end of the rotating shaft 20 through a coupling 19, so that the power of the speed-regulating motor 17 is transmitted to the rotating shaft 20. The bearing seat is arranged in the middle of the supporting base 4 and far away from the adjustable speed motor 17, and the other end of the rotating shaft 20 is supported on the bearing seat through a bearing 12. The rotary plate 22 is fixedly disposed on the rotary shaft 20, and the rotary plate 22 is fixedly disposed between the governor motor 17 and the bearing housing, so that the power of the rotary shaft 20 can be transmitted to the rotary plate 22.

Further, the bearing seat includes an L-shaped bearing seat 12 and a T-shaped bearing seat 16, and the L-shaped bearing seat 12 and the T-shaped bearing seat 16 can be fixedly arranged on the support base 4 through a bearing seat fixing bolt 37; meanwhile, the L-shaped bearing housing 12 and the T-shaped bearing housing 17 are respectively disposed at both sides of the rotating disc 22, and the rotating shaft 20 sequentially penetrates through the T-shaped bearing housing 17, the rotating disc 22 and the L-shaped bearing housing 12, so that the rotating disc 22 can be further stably supported between the L-shaped bearing housing 12 and the T-shaped bearing housing 17 to output a stable exciting force, and the exciting device 3 can be disassembled and assembled according to actual requirements to adjust a distance between the exciting device 3 and the first fixed magnet 27 and/or the second fixed magnet 29.

As an embodiment of the present invention, the rotating disc 22 includes two circular rotating bodies 34 and a connecting shaft 15 disposed between the two rotating bodies 34.

Wherein, two the relative one side of rotator 34 all has a plurality of mounting grooves (not sign in the figure) of circumference equipartition correspondingly, and this mounting groove suits with the both ends of above-mentioned moving magnet 21 so that install a plurality of moving magnet 21 between two rotators 34. In the present embodiment, the number of mounting grooves is set to 8. Both ends of the connecting shaft 15 may be stably connected to the centers of the two rotating bodies 34 through the flanges 14, and the connecting shaft 15 may be fixedly sleeved on the rotating shaft 20 through a bushing, so that the moving magnet 21 may be stably mounted on the rotating disc 22 to stably output an exciting force.

As an embodiment of the present invention, as shown in fig. 4, the two sides of the single lap bolt joint supporting seat 8 are symmetrically and fixedly provided with the slide rails 23, and the slide blocks 24 are slidably provided on the slide rails 23, so that the slide blocks 24 can slide relative to the slide rails 23. Meanwhile, two sides of the single lap bolt joint connecting plate 25 are respectively and fixedly arranged on the sliding blocks 24, so that the single lap bolt joint connecting plate 25 can slide relative to the sliding rail 23, the distance between the first fixed magnet 27 and the movable magnet 21 on the excitation device 3 can be adjusted, and the excitation force of the excitation device 3 on the first bolt 26 to be detected can be adjusted. In addition, a plurality of third screw through holes 33 are formed in the middle of the single lap bolt joint connection plate 25, and the plurality of third screw through holes 33 correspond to the first screw through holes 31, so that the first bolt 26 to be tested can be mounted on the single lap bolt joint test stand 2 to perform a vibration failure test

Further, the sliding block 24 may be electrically connected to a computer system in the collecting and analyzing device, so that the distance between the first fixed magnet 27 and the moving magnet 21 may be manually/automatically adjusted as required, and the excitation force of the excitation device 3 on the first bolt 26 to be tested may be further adjusted.

As an embodiment of the present invention, as shown in fig. 5, a plurality of fourth threaded through holes (not marked in the figure) are provided at the middle of the above-mentioned double-lap bolt joint connecting plate 28, and correspond to the above-mentioned second threaded through hole 32, so that the second bolt 30 to be tested can be installed on the double-lap bolt joint test bed 5 for the vibration failure test.

As an embodiment of the present invention, the first threaded through hole 31, the second threaded through hole 32, the third threaded through hole 33, and the fourth threaded through hole can be customized according to actual needs, i.e., can be designed into threaded through holes of different sizes according to actual needs. Of course, the first threaded through hole 31, the second threaded through hole 32, the third threaded through hole 33 and the fourth threaded through hole may also be designed as threaded through holes of the same size, and at this time, the first bolt to be measured 26 and the second bolt to be measured 30 are bolts to be measured of the same size.

For better explain and fully disclose above-mentioned magnetic force excitation bolted joint vibration inefficacy experimental apparatus, the utility model discloses this magnetic force excitation bolted joint vibration inefficacy experimental apparatus's test method is still provided, specifically as follows:

the first test method is used for carrying out a single lap joint bolt joint vibration failure experiment:

firstly, the position of the single lap bolt joint connecting plate 25 is manually or automatically adjusted through the slider 24 to adjust the distance between the first fixed magnet 27 on the single lap bolt joint connecting plate 25 and the movable magnet 21 on the rotating disc 22, namely the shortest distance between the first fixed magnet 27 and one movable magnet 21, as shown in fig. 1, which is the horizontal distance between the first fixed magnet 27 and one movable magnet 21, so as to adjust the stress of the first bolt 26 to be measured;

then, screwing a plurality of first bolts to be tested 26 from the single lap joint bolt joint connecting plate 25 in a certain sequence and arrangement until the bolts are screwed into the single lap joint bolt joint supporting seat 8, and fixing the plurality of first bolts to be tested 26 on the single lap joint bolt joint supporting seat 8 according to a certain pretightening force;

then, installing the acceleration sensor 1 and the displacement sensor 7 on a single lap-joint bolt joint connecting plate 25, correspondingly installing a plurality of strain sensors 6 on a plurality of first bolts 26 to be measured, electrically connecting the acceleration sensor 1 and the displacement sensor 7 with a data collector in an acquisition and analysis device, electrically connecting the strain sensors 6 with a dynamic strain gauge in the acquisition and analysis device, electrically connecting the data collector and the dynamic strain gauge with a computer system in the acquisition and analysis device, adjusting the rotating speed of a driving motor (or a speed regulating motor 17) through a response signal of the acceleration sensor 1 to output a proper excitation magnetic force (or excitation force), and starting a vibration failure experiment of the single lap-joint bolt joint;

and finally, according to the acceleration signal acquired by the acceleration sensor 1, the displacement signal acquired by the displacement sensor 7 and the strain signal acquired by the strain sensor 6 in the acquisition and analysis device, drawing by a computer system in the acquisition and analysis device to obtain a load-displacement curve and a rigidity-displacement curve, then obtaining a load-fatigue cycle time curve and a fatigue rigidity-cycle time curve, namely a failure curve, according to the load-displacement curve and the rigidity-displacement curve, and judging the main failure form and the failure load (or failure critical value) of the single lap joint bolt joint through the failure curve.

The second test method is to perform a double lap joint bolt joint vibration failure test:

firstly, inserting the double lap-joint bolt joint connecting plate 28 between the double lap-joint bolt joint supporting seats 10 to keep a certain distance between the second fixed magnet 29 on the double lap-joint bolt joint connecting plate 28 and the movable magnet 21 on the rotating disc 22, namely, adjusting the shortest distance between the second fixed magnet 29 and a certain movable magnet 21, as shown in fig. 1, which is the horizontal distance between the second fixed magnet 29 and a certain movable magnet 21, so as to adjust the stress magnitude of the second bolt 30 to be tested;

then, screwing a plurality of second bolts 30 to be tested into the double-lap-joint bolt joint support seat 10 according to a certain sequence and arrangement, penetrating through the double-lap-joint bolt joint connecting plate 28 until being screwed into the double-lap-joint bolt joint support seat 10 again, and fixing the plurality of second bolts 30 to be tested onto the double-lap-joint bolt joint support seat 10 according to a certain pretightening force;

then, the acceleration sensor 1 and the displacement sensor 7 are installed on the double-lap-joint bolt joint connecting plate 28, the plurality of strain sensors 6 are correspondingly installed on the plurality of second bolts 30 to be tested, the acceleration sensor 1 and the displacement sensor 7 are electrically connected with a data collector in the acquisition and analysis device, the strain sensors 6 are electrically connected with a dynamic strain gauge in the acquisition and analysis device, the data collector and the dynamic strain gauge are electrically connected with a computer system in the acquisition and analysis device, the rotating speed of the driving motor (or the speed regulating motor 17) is adjusted through a response signal of the acceleration sensor 1 so as to output proper excitation magnetic force (or excitation force), and a vibration failure experiment of the double-lap-joint bolt joint is started;

and finally, according to the acceleration signal acquired by the acceleration sensor 1, the displacement signal acquired by the displacement sensor 7 and the strain signal acquired by the strain sensor 6 in the acquisition and analysis device, drawing by a computer system in the acquisition and analysis device to obtain a load-displacement curve and a rigidity-displacement curve, then obtaining a load-fatigue cycle time curve and a fatigue rigidity-cycle time curve, namely a failure curve, according to the load-displacement curve and the rigidity-displacement curve, and judging the main failure form and the failure load of the double-lap-joint bolt joint through the failure curve.

In the third test method, a comparison experiment of the vibration failure of the single-lap-joint bolt joint and the double-lap-joint bolt joint is carried out simultaneously:

firstly, adjusting the positions of a motor base 18, an L-shaped bearing base 13 and a T-shaped bearing base 16 to fix an excitation device 3 between a single lap bolt joint support 8 and a double lap bolt joint support 10, manually or automatically adjusting the position of a single lap bolt joint connecting plate 25 through a slider 24 to adjust the horizontal distance between a first fixed magnet 27 on the single lap bolt joint connecting plate 25 and a certain movable magnet 21 on a rotating disc 22, and inserting a double lap bolt joint connecting plate 28 between the double lap bolt joint support 10 to adjust the horizontal distance between a second fixed magnet 29 on the double lap bolt joint connecting plate 28 and a certain movable magnet 21 on the rotating disc 22 so as to enable the horizontal distances between the first fixed magnet 27 and the second fixed magnet 29 and two movable magnets 21 oppositely arranged on the same horizontal plane to be equal;

then, screwing a plurality of first bolts to be tested 26 from the single lap joint bolt joint connecting plate 25 in a certain sequence and arrangement until the bolts are screwed into the single lap joint bolt joint supporting seat 8, and fixing the plurality of first bolts to be tested 26 on the single lap joint bolt joint supporting seat 8 according to a certain pretightening force; screwing a plurality of second bolts 30 to be tested into the double-lap-joint bolt joint supporting seat 10 according to a certain sequence and arrangement, penetrating through the double-lap-joint bolt joint connecting plate 28 until being screwed into the double-lap-joint bolt joint supporting seat 10 again, and fixing the plurality of second bolts 30 to be tested onto the double-lap-joint bolt joint supporting seat 10 according to a certain pretightening force; at this time, in order to perform a comparison experiment of the vibration failure of the single lap joint bolt joint and the double lap joint bolt joint, the first bolt to be tested 26 and the second bolt to be tested 30 are set as bolts to be tested with the same specification, and the variables such as the arrangement mode, the pretightening force and the like which may influence the experiment effect are kept consistent;

then, the acceleration sensor 1 and the displacement sensor 7 are installed on the single lap-joint bolt joint connecting plate 25 and the double lap-joint bolt joint connecting plate 28, the plurality of strain sensors 6 are correspondingly installed on the plurality of first bolts to be tested 26 and the plurality of second bolts to be tested 30, the acceleration sensor 1 and the displacement sensor 7 are electrically connected with a data collector in an acquisition and analysis device, the strain sensor 6 is electrically connected with a dynamic strain gauge in the acquisition and analysis device, the data collector and the dynamic strain gauge are electrically connected with a computer system in the acquisition and analysis device, and the rotating speed of the driving motor (or the speed regulating motor 17) is adjusted through a response signal of the acceleration sensor 1 to output proper excitation magnetic force (or excitation force) so as to start a vibration failure experiment of the double lap-joint bolt joint;

and finally, respectively drawing load-displacement curves and rigidity-displacement curves of the single-lap-joint bolt joint and the double-lap-joint bolt joint through a computer system according to the acceleration signals collected by the acceleration sensor 1, the displacement signals collected by the displacement sensor 7 and the strain signals collected by the strain sensor 6 in the collecting and analyzing device, then drawing load-fatigue cycle times curves and fatigue rigidity-cycle times curves of the single-lap-joint bolt joint and the double-lap-joint bolt joint in the same graph according to the load-displacement curves and the rigidity-displacement curves, namely failure curves of the single-lap-joint bolt joint and the double-lap-joint bolt joint, and judging the vibration failure modes and respective failure critical values of the single-lap-joint bolt joint and the double-lap-joint bolt joint through the failure curves.

The utility model discloses usable acceleration sensor, displacement sensor and strain sensor acquire the acceleration signal, the displacement signal and the strain signal of the bolt that awaits measuring respectively to carry out integrated analysis, operation to above-mentioned acceleration signal, displacement signal and strain signal through computer system, in order to draw and obtain load-displacement curve and rigidity-displacement curve, and can finally obtain load-fatigue cycle number curve and fatigue rigidity-cycle number curve according to above-mentioned two kinds of curves, the curve that becomes invalid promptly. In other words, the utility model discloses usable acceleration sensor carries out vibration test, tests the acceleration signal (or vibration signal) of being surveyed the bolt promptly, utilizes displacement sensor to carry out the slip test, tests the slip distance of being surveyed the bolt interface promptly, utilizes strain transducer to carry out the deformation test, tests the hole week that the inefficacy load (or inefficacy critical excitation value) drives promptly and meets an emergency, and give data collection station and dynamic strain gauge with above-mentioned acceleration signal, slip distance signal and hole week strain signal transmission, and unified conveying again carries out data analysis to computer system; the computer system can study the deformation and the slip condition of the bolt joint caused by vibration according to the signals, draw and obtain a load-displacement curve (as shown in figure 9) and a rigidity-displacement curve (as shown in figure 10), further study the failure conditions of the bolt joint caused by vibration, such as thread loosening, connected piece slipping, vibration fatigue and the like, and obtain a load-fatigue cycle number curve (as shown in figure 11) and a fatigue rigidity-cycle number curve (as shown in figure 12) for judging the main failure mode of the bolt joint.

The above description is only the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can substitute or change the technical solution and the improvement concept of the present invention within the technical scope disclosed in the present invention.

Claims (10)

1. The utility model provides a magnetic force excitation bolted joint vibration failure test device which characterized in that: the device comprises a supporting base, an excitation device, a testing device and an acquisition and analysis device;

the excitation device comprises a driving motor, a rotating disk and a movable magnet, the driving motor is arranged on one side of the middle part of the supporting base, the output end of the driving motor is connected with the rotating disk, a plurality of movable magnets are uniformly distributed on the rotating disk in the circumferential direction, and the N poles or the S poles of the plurality of movable magnets face outwards;

a single-lap-joint bolt joint supporting seat and a double-lap-joint bolt joint supporting seat are respectively arranged at two ends of the supporting base;

the testing device comprises a single lap-joint bolt joint connecting plate, a double lap-joint bolt joint connecting plate, a displacement sensor, a strain sensor, an acceleration sensor, a first fixed magnet and a second fixed magnet, wherein the single lap-joint bolt joint connecting plate is slidably arranged on the single lap-joint bolt joint supporting seat, the double lap-joint bolt joint connecting plate is detachably arranged on the double lap-joint bolt joint supporting seat, the first fixed magnet and the second fixed magnet are respectively and fixedly arranged at one ends, close to the rotating disc, of the single lap-joint bolt joint connecting plate and the double lap-joint bolt joint connecting plate, the displacement sensor and the acceleration sensor are respectively arranged on the single lap-joint bolt joint connecting plate and the double lap-joint bolt joint connecting plate, a plurality of thread through holes are respectively and correspondingly arranged on the single lap-joint bolt joint supporting seat, the double lap-joint bolt joint connecting plate and the double lap-joint bolt joint supporting seat, the threaded through holes are matched with the tested bolts, and the tested bolts are provided with the strain sensors;

the acquisition and analysis device is respectively electrically connected with the displacement sensor, the strain sensor and the acceleration sensor.

2. The magnetic force excitation bolt joint vibration failure experimental device of claim 1, characterized in that: and the N pole or the S pole of each of the first fixed magnet and the second fixed magnet is opposite to the N pole or the S pole of the movable magnet.

3. The magnetic force excitation bolt joint vibration failure experimental device of claim 1, characterized in that: the number of the moving magnets is 2-8.

4. The magnetic force excitation bolt joint vibration failure experimental device of claim 1, characterized in that: the driving motor is set as a speed regulating motor, and the speed regulating motor is electrically connected with the acquisition and analysis device.

5. The magnetic force excitation bolt joint vibration failure experimental device of claim 1, characterized in that: the vibration excitation device further comprises a rotating shaft and a bearing seat, the bearing seat is arranged in the middle of the supporting base and far away from the driving motor, one end of the rotating shaft is connected with the output end of the driving motor, the other end of the rotating shaft is supported on the bearing seat, and the rotating disc is fixedly arranged on the rotating shaft and arranged between the driving motor and the bearing seat.

6. The magnetic force actuated bolted joint vibration failure experimental apparatus of claim 5, characterized in that: the rotary disk comprises two rotating bodies and a connecting shaft arranged between the rotating bodies, wherein a plurality of mounting grooves are uniformly distributed in the circumferential direction on one side, opposite to the rotating bodies, of each rotating body correspondingly, the two ends of the movable magnet are correspondingly and respectively fixedly arranged in the mounting grooves, the two ends of the connecting shaft are respectively connected with the centers of the two rotating bodies, and the connecting shaft is fixedly sleeved on the rotating shaft.

7. The magnetic force actuated bolted joint vibration failure experimental apparatus of claim 5, characterized in that: the vibration excitation device further comprises a motor base, the driving motor is fixedly arranged on the motor base, the motor base is fixedly arranged on the supporting base through a fixing bolt, and the axial lead of the driving motor is consistent with that of the bearing hole of the bearing base.

8. The magnetic force excitation bolt joint vibration failure experimental device of claim 1, characterized in that: a plurality of first threaded through holes are arrayed on the single-lap-joint bolt joint supporting seat, and a plurality of second threaded through holes are arrayed on the double-lap-joint bolt joint supporting seat; the single-lap-joint bolt joint connecting plate is provided with a plurality of third threaded through holes corresponding to the first threaded through holes, and the double-lap-joint bolt joint connecting plate is provided with a plurality of fourth threaded through holes corresponding to the second threaded through holes.

9. The magnetic force excitation bolt joint vibration failure experimental device of claim 1, characterized in that: the two sides of the single-lap-joint bolt joint supporting seat are symmetrically and fixedly provided with slideways, sliding blocks are arranged on the slideways in a sliding mode, the two sides of the single-lap-joint bolt joint connecting plate are fixedly arranged on the sliding blocks respectively, and the sliding blocks are electrically connected with the acquisition and analysis device.

10. The magnetic force excitation bolt joint vibration failure experimental device of claim 1, characterized in that: the double-lap-joint bolt joint supporting seat comprises a bottom plate and a top plate which are integrally formed, and the double-lap-joint bolt joint connecting plate is detachably arranged between the bottom plate and the top plate.

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