CN210774737U - Multi-axial fatigue vibration rack for rail vehicle - Google Patents

Multi-axial fatigue vibration rack for rail vehicle Download PDF

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Publication number
CN210774737U
CN210774737U CN201921975055.9U CN201921975055U CN210774737U CN 210774737 U CN210774737 U CN 210774737U CN 201921975055 U CN201921975055 U CN 201921975055U CN 210774737 U CN210774737 U CN 210774737U
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China
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hydraulic servo
hydraulic
electro
rail vehicle
cylinder
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CN201921975055.9U
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Chinese (zh)
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陈宽裕
阳光武
肖守讷
杨冰
朱涛
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Southwest Jiaotong University
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Southwest Jiaotong University
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Abstract

The utility model provides a rail vehicle multiaxis fatigue vibration rack belongs to vibration test technical field. The vibrating table body is of a flat cylinder structure, the upper ejector block is a polyhedron of which the inner side is matched with the chute surface, the inclined surfaces on the two sides are provided with spring mounting holes, a radiation line which passes through the bottom plate and has a circle center included angle of 120 degrees is respectively provided with a bidirectional ejector block of which the inner side is provided with two inclined surfaces, a transverse reinforcing rod of which the two ends are guide grooves is arranged between every two bidirectional ejector blocks, and one end of an electro-hydraulic servo actuator is connected with a flange plate at the upper end of a hydraulic servo valve through a bolt; the hydraulic actuating cylinder is connected with the lower end of the hydraulic servo valve through a piston rod, and the bottom of the hydraulic actuating cylinder is tightly abutted to an inclined plane on the inner side of the bidirectional top block; the other end of the electro-hydraulic servo actuator is connected with a positioning mounting rod at the upper end of the air spring through a flange and a hydraulic force transmission cylinder; a laminated air spring is arranged between the bottom surface of the vibration table body and the bottom plate.

Description

Multi-axial fatigue vibration rack for rail vehicle
Technical Field
The utility model belongs to the technical field of fatigue vibration test.
Background
In recent years, the rail transit industry in China is rapidly developed, the running speed of trains is continuously improved, the impact force, the steering force, the braking force and the like on a train suspension part are more and more complex at higher and higher speeds, and each part on the train is inevitably subjected to certain fatigue damage after long-time service work. According to statistics, more than 80% of parts on a train are damaged by fatigue, so the problem of fatigue life of key parts of the train is more and more important. Generally, a great deal of effort is needed to directly test fatigue endurance tests of a whole vehicle, so that endurance tests can be efficiently performed, a multi-axis vibration table is generally needed to be used for connecting tested parts, operation loads are simulated, and the multi-axis vibration table for rail transit is quite lacking.
At present, according to different system implementation modes, a multi-axis test bed can be divided into motor drive or electro-hydraulic drive and the like, and the motor drive has the advantages that a hydraulic oil source and a matched pipeline system are not needed, so that the cost is reduced, the system noise is low, but the interference is large, the idle return stroke of the system is more, and the operation temperature is high; the electro-hydraulic servo drive can bear larger load, the idle return stroke of the system is small, the precision is higher, but the vibration frequency of the electro-hydraulic servo actuator is lower. According to different actuator layout modes, the multi-axis test bed can be divided into a Stewart type parallel vibration bed, an orthogonal arrangement mode vibration bed and the like, the Stewart type parallel vibration bed is ingenious in implementation mode, and the movement stroke in the rotation direction is large; the traditional orthogonal arrangement mode vibration table is high in bearing capacity and strong in anti-overturning moment, and due to the fact that excessive connecting mechanisms are introduced, acceleration is prone to distortion, abrasion and idle return are prone to occurring, and therefore response accuracy of the system is reduced.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a rail vehicle multiaxis fatigue vibration rack, it can simulate the technical problem that the load condition when the train operation carries out endurance test effectively.
The purpose of the utility model is realized by the following technical scheme:
a rail vehicle multi-axial fatigue vibration rack comprises a vibration rack body, an electro-hydraulic servo actuator and a bottom plate, wherein the vibration rack body is of a flat cylinder structure with a top plate, the diameter of the top plate of the cylinder is larger than that of the cylinder, bolt holes are uniformly arranged on the surface of the top plate, the outer wall of the cylinder is a chute surface which is arranged at intervals, and vertical inverted T-shaped grooves are uniformly distributed on two sides of the chute surface; the upper top blocks are polyhedrons, the inner sides of which are matched with the chute surfaces, the upper parts of the upper top blocks are of inverted V-shaped structures, the inclined surfaces of the two sides of each structure are provided with spring mounting holes, and the three upper top blocks are uniformly distributed on the outer wall of the cylinder body of the vibrating table body in an 120-degree manner; two-way ejector blocks with two inclined planes on the inner sides are respectively arranged on radial lines with the included angle of the circle center of the through bottom plate being 120 degrees, transverse reinforcing rods are arranged between every two three two-way ejector blocks, a guide groove for placing a hydraulic servo valve and having a slope is arranged at each of two ends of each transverse reinforcing rod, and one end of an electro-hydraulic servo actuator is connected with a flange plate at the upper end of the hydraulic servo valve through a bolt; the hydraulic actuating cylinder is connected with the lower end of the hydraulic servo valve through a piston rod, and the bottom of the hydraulic actuating cylinder is tightly abutted to an inclined plane on the inner side of the bidirectional top block; the other end of the electro-hydraulic servo actuator is connected with a hydraulic force transmission cylinder with an air spring air inlet through a flange; the air inlet at the lower end of the air spring is in interference fit with the air inlet of the air spring, and the positioning and mounting rod at the upper end of the air spring is in interference fit connection with the spring mounting holes at the two sides of the upper top block; a laminated spring is arranged between the bottom surface of the vibrating table body and the bottom plate.
The inner part and the bottom surface of the cylinder body of the vibration table body are of a net-shaped thin-wall reinforcing rib structure, and the net-shaped thin-wall reinforcing rib is connected with a main bearing structure through three main force transmission ribs distributed in an isosceles triangle.
The inclined planes on two sides of the inverted-splayed structure of the upper ejector block are connection points of air springs (3) at the upper end of the electro-hydraulic servo actuator, and the bottom structure of the upper ejector block is in abutting contact with the excircle rib at the bottom surface of the vibrating table body.
The hydraulic servo valve also comprises a displacement sensor and a load sensor.
The bidirectional top block and the transverse reinforcing rod are fixedly connected with the bottom plate through bolts;
the middle part of the transverse reinforcing rod is fixed with the bottom of the vertical reinforcing rod, and the top of the vertical reinforcing rod is fixed with the oblique pull rod;
the transverse reinforcing rod, the vertical reinforcing rod and the oblique pull rod are all hollow extruded sections.
Furthermore, the reinforcing rods at least comprise two guide grooves, two vertical reinforcing rods, two oblique reinforcing pull rods fixedly connected with the guide grooves and the vertical reinforcing rods, and two transverse pull rods fixedly connected with the floor; the electro-hydraulic servo actuator realizes reciprocating motion in the guide groove; the two sides of the reinforcing rod are provided with object blocks which are connected with the two-way jacking blocks at the two sides, so that stress is balanced.
Further, the air spring comprises an air bag, a positioning installation rod and an air inlet hole; the positioning and mounting rods are arranged in spring mounting holes on two sides of the inverted eight-shaped upper top block, and the air inlet holes are arranged in hydraulic actuating cylinders of the electro-hydraulic servo actuator and are in interference fit; the air inlet hole can be accessed with compressed air from the inside, so that the rigidity changing control is carried out.
Compared with the prior art, the utility model discloses beneficial effect lies in: a rail vehicle multi-axis fatigue vibration rack adopts a parallel vibration rack, can completely and accurately simulate the motion states of nodding, shaking, floating and sinking and the like of a train during operation, and more truly restore the stress state of a train suspension part; the structure is compact, and the occupied area is small; the laminated air spring is additionally arranged below the vibrating table, and the hydraulic servo valve and the hydraulic actuating cylinder are arranged in the laminated air spring, so that three-way excitation can be caused, and the defect that the anti-overturning moment of the parallel vibrating table is poor is greatly improved; by adopting the electro-hydraulic servo driving device, the vibration is more stable, and the device has the characteristics of large displacement, high load, large thrust, good low-frequency effect and the like; the vibration table frame is designed in a lightweight mode, aluminum alloy extruded sections are adopted, the structure is a reinforcing rib thin-wall structure, the quality of the vibration table frame can be effectively reduced, and the defects that an electro-hydraulic servo driving device is low in working frequency range, large in high-frequency waveform distortion and the like are overcome, so that the running condition of a train under medium and high frequency can be simulated accurately.
Drawings
FIG. 1 is a schematic view of the overall structure of the present invention;
fig. 2 is a schematic view of the force transfer structure of the present invention;
FIG. 3 is a schematic view of the top structure of the vibrating table body of the present invention;
FIG. 4 is a bottom view of the vibrating table of the present invention;
fig. 5 is a schematic view of the electro-hydraulic servo driving device of the present invention;
FIG. 6 is a schematic view of the stiffener assembly according to the present invention;
FIG. 7 is a schematic view of an air spring according to the present invention;
fig. 8 is a schematic view of a laminated spring according to the present invention;
fig. 9 is a schematic view of the upper top block of the present invention;
Detailed Description
The following description will further describe embodiments of the present invention with reference to the accompanying drawings.
As shown in fig. 1 to 5, the multi-axial fatigue vibration rack for the rail vehicle comprises a vibration rack body 2, an electro-hydraulic servo actuator 5, an upper top block 13, a bidirectional top block 8 fixed on the surface of a bottom plate 15, a guide groove 10 for fixing the electro-hydraulic servo actuator, a transverse reinforcing rod 11, a laminated spring 9 and an air spring 3; the side wall 24 of the vibration rack is matched with three upper top blocks 13, the upper top blocks 13 are of an inverted eight-shaped two-side stress structure, are fixed in an inverted T-shaped groove 16 and can be detached for use, and are connected with a positioning and mounting rod 27 of the variable-stiffness air spring 3 in an interference fit manner through a spring mounting hole 26; wherein, the other side of the air spring 3 is provided with an air inlet hole 23, and the air inlet hole 23 is connected with an air spring air inlet 22 of the electro-hydraulic servo actuator in an interference fit manner; the laminated spring 9 is arranged on the bottom plate 15 and the bottom surface of the vibration table frame, a hydraulic servo valve and a hydraulic actuating cylinder (not shown in the figure) are arranged in the spring, three-way excitation can be caused, and the defect that the anti-overturning moment of the parallel vibration table is inferior is greatly improved; the hydraulic servo valve 6 is arranged in the guide groove 10 and can realize reciprocating motion with multiple degrees of freedom, one end of the electro-hydraulic servo actuator 5 is matched with the air spring 3 to apply force, the other end of the electro-hydraulic servo actuator is propped against the bidirectional top block 8 to bear force, and the bidirectional top block 8 is fixedly connected with the bottom plate 15 and is mutually connected through the transverse reinforcing rod 11 to balance the force of the electro-hydraulic servo actuator 5 on the bidirectional top block 8; the transverse reinforcing rods 11, the vertical reinforcing rods 12 and the oblique pull rods 14 are all made of hollow extruded sections, so that the strength is ensured, and the whole light weight is realized.
Further, as shown in fig. 2, 3 and 4, the vibration table 2 is in a circular regular structure, and the top surface of the vibration table is provided with regular bolt holes 1; when a vibration test is carried out, a tested suspension part is required to be connected to the surface of a vibration table through a bolt; the bottom surface of the steel tube is of a reinforcing rib thin-wall structure and mainly comprises a main bearing structure 18, an inner ring rib, an outer ring rib, a main force transmission rib 25, an auxiliary force transmission rib, an inner scattering rib and an outer circular rib 17; during force transmission, the upper top block 13 transmits force to the main force bearing structure 18, and then the force is borne by 3 main force transmission ribs 25 distributed in a triangular manner, and the peripheral and radial distribution of the rest rib plates divides the table body into a plurality of quadrilateral areas for sharing the force transmitted by the electro-hydraulic servo actuator 5 in each direction; meanwhile, the platform body adopts a reinforcing rib thin-wall structure, so that the quality of the vibration platform frame can be effectively reduced, and the running condition of the train under medium and high frequency can be simulated more accurately.
Further, as shown in fig. 5, 6 and 7, one end of the electro-hydraulic servo actuator 5 is connected with a flange 20 at the upper end of the hydraulic servo valve 6 through a bolt 21; the hydraulic actuating cylinder 7 is connected with the lower end of the hydraulic servo valve 6 through a piston rod 19, and the bottom of the hydraulic actuating cylinder 7 is tightly abutted with an inclined plane on the inner side of the bidirectional top block 8; the other end of the electro-hydraulic servo actuator 5 is connected with a hydraulic force transmission cylinder 4 with an air spring air inlet 22 through a flange; an air spring air inlet 22; when the pneumatic hydraulic actuator works, the hydraulic actuator cylinder 7 is fixed, high-pressure oil provided by an oil pump enters the action oil cylinder through a hydraulic servo valve 6 in a proper amount, the servo valve generates a load pressure difference action, the load pressure difference action is exerted on a piston of the hydraulic cylinder, the piston 19 is pushed to move, force is transmitted to the hydraulic force transmission cylinder 4, and force is exerted on the air spring 3 with variable rigidity and the upper ejector block 13; at present, an actuator and a vibration table frame are rigidly connected, and after the air springs 3 with variable rigidity are additionally arranged, compressed air is injected into three independent air springs 3 through external air compression equipment before a test, and the rigidity and the damping of the air springs 3 are changed, so that the test requirements can be matched; the hydraulic servo valve 6 further comprises a displacement sensor, a load sensor and a pressure sensor (not shown in the figure), and is used for detecting and converting a feedback voltage signal and comparing the feedback voltage signal with a command voltage signal, so as to obtain a deviation voltage signal and output a force value specified by a specified signal.
The following describes the working process of the multi-axial fatigue vibration stand of the rail vehicle when simulating the vibration of the rail vehicle in all directions. When the vehicle is simulated to do telescopic motion, the two electro-hydraulic servo actuators 5 on the bidirectional jacking block 8 actively stretch, the corresponding laminated springs 9 do small-amplitude transverse motion, and other actuators do small-range motion to eliminate the traction motion, so that the telescopic motion can be finished; when the vehicle is simulated to float and sink, the three laminated springs 9 do main vertical reciprocating motion, and the other six actuators do small-range motion to eliminate the traction motion, so that the float and sink motion can be finished; when the yaw motion of the vehicle is simulated, the two electro-hydraulic servo actuators 5 on the right bidirectional top block 8 actively stretch out and draw back, the corresponding laminated springs 9 make small-amplitude transverse motion, and other actuators move in a small range to eliminate the traction motion, so that the right active yaw motion can be completed; the active transverse swinging motion on the left side is the same, the two electro-hydraulic servo actuators 5 positioned on the left bidirectional top block of the vibration rack act simultaneously, and the transverse swinging motion can be completed by extending and retracting the left side and the right side to do opposite motion; when vehicle nodding motion is simulated, the two electro-hydraulic servo actuators 5 on the bidirectional top block 8 actively stretch out and draw back, meanwhile, the laminated springs 9 opposite to the two electro-hydraulic servo actuators make vertical motion to a large extent, and other actuators move in a small range to eliminate the traction motion, so that nodding motion can be completed; when the vehicle shaking motion is simulated, the electro-hydraulic servo actuators 5 on the same side of each two-way ejector block 8 actively stretch out and draw back, the electro-hydraulic servo actuators 5 on the other side do opposite motion, the laminated springs 9 do small-amplitude transverse motion to eliminate the traction motion, and then the shaking motion can be completed; when the vehicle rolling motion is simulated, the four electro-hydraulic servo actuators 5 on the left and right two-way jacking blocks actively stretch out and draw back, the corresponding laminated springs 9 vertically move to a large extent, and the other actuators move in a small range to eliminate the traction motion, so that the rolling motion can be completed.
The six electro-hydraulic servo actuators and the three laminated springs 9 are simultaneously coordinated and loaded according to the set waveform phase, so that the real loading condition of a rail vehicle suspension part during the running of a train can be simulated, and the fatigue endurance test is carried out.
The embodiments of the present invention should not be construed as limiting the scope of the present invention, and any modifications, equivalent replacements, and improvements that can be made by a person skilled in the art within the spirit and principle of the present invention are also included in the protection scope of the present invention.

Claims (7)

1. The utility model provides a rail vehicle multiaxis fatigue vibration rack, includes the shaking table body (2), electro-hydraulic servo actuator (5) and bottom plate (15), its characterized in that: the vibrating table body (2) is in a flat cylinder structure with a top plate, the diameter of the top plate of the cylinder body is larger than that of the cylinder body, bolt holes (1) are uniformly arranged on the plate surface, the outer wall of the cylinder body is provided with sliding groove surfaces (24) arranged at intervals, and vertical inverted T-shaped grooves (16) are uniformly distributed on two sides of each sliding groove surface (24); the upper ejector blocks (13) are polyhedrons, the inner sides of the polyhedrons are matched with the sliding groove surfaces (24), the upper parts of the upper ejector blocks are of inverted V-shaped structures, the inclined surfaces of the two sides of each structure are provided with spring mounting holes (26), and the three upper ejector blocks (13) are uniformly distributed on the outer wall of the cylinder body of the vibrating table body (2) at an angle of 120 degrees; the radial line which passes through the bottom plate (15) and has a circle center included angle of 120 degrees is respectively provided with a bidirectional ejector block (8) with two inclined planes on the inner side, a transverse reinforcing rod (11) is arranged between every two of the three bidirectional ejector blocks (8), two ends of each transverse reinforcing rod (11) are respectively provided with a guide groove (10) which is used for placing a hydraulic servo valve (6) and is provided with a slope, and one end of an electro-hydraulic servo actuator (5) is connected with a flange plate (20) at the upper end of the hydraulic servo valve (6) through a bolt (21); the hydraulic actuating cylinder (7) is connected with the lower end of the hydraulic servo valve (6) through a piston rod (19), and the bottom of the hydraulic actuating cylinder (7) is tightly abutted to an inclined plane on the inner side of the bidirectional top block (8); the other end of the electro-hydraulic servo actuator (5) is connected with a hydraulic force transmission cylinder (4) with an air spring air inlet (22) through a flange; an air inlet (23) at the lower end of the air spring (3) is in interference fit with an air inlet (22) of the air spring, and a positioning mounting rod (27) at the upper end of the air spring (3) is in interference fit connection with spring mounting holes (26) at two sides of the upper top block (13); a laminated spring (9) is arranged between the bottom surface of the vibration table body (2) and the bottom plate (15).
2. A rail vehicle multi-axial fatigue vibration stand as claimed in claim 1, wherein: the inner part and the bottom surface of the cylinder of the vibration table body (2) are of a net-shaped thin-wall reinforcing rib structure, and the net-shaped thin-wall reinforcing rib is connected with a main bearing structure (18) through three main force transmission ribs (25) distributed in an isosceles triangle.
3. A rail vehicle multi-axial fatigue vibration stand as claimed in claim 1, wherein: the inclined planes on two sides of the inverted splayed structure of the upper ejector block (13) are connection points of air springs (3) at the upper end of the electro-hydraulic servo actuator (5), and the bottom structure of the upper ejector block (13) is in butt contact with outer circular ribs (17) of the bottom surface of the vibrating table body (2).
4. A rail vehicle multi-axial fatigue vibration stand as claimed in claim 1, wherein: the hydraulic servo valve (6) further comprises a displacement sensor and a load sensor.
5. A rail vehicle multi-axial fatigue vibration stand as claimed in claim 1, wherein: the bidirectional top block (8) and the transverse reinforcing rod (11) are fixedly connected with the bottom plate (15) through bolts.
6. A rail vehicle multi-axial fatigue vibration stand as claimed in claim 1, wherein: the middle part of the transverse reinforcing rod (11) is fixed with the bottom of the vertical reinforcing rod (12), and the top of the vertical reinforcing rod (12) is fixed with the oblique pull rod (14).
7. A rail vehicle multi-axial fatigue vibration stand as claimed in claim 1, wherein: the transverse reinforcing rods (11), the vertical reinforcing rods (12) and the oblique pull rods (14) are all hollow extruded sections.
CN201921975055.9U 2019-11-15 2019-11-15 Multi-axial fatigue vibration rack for rail vehicle Withdrawn - After Issue CN210774737U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201921975055.9U CN210774737U (en) 2019-11-15 2019-11-15 Multi-axial fatigue vibration rack for rail vehicle

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201921975055.9U CN210774737U (en) 2019-11-15 2019-11-15 Multi-axial fatigue vibration rack for rail vehicle

Publications (1)

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CN210774737U true CN210774737U (en) 2020-06-16

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CN201921975055.9U Withdrawn - After Issue CN210774737U (en) 2019-11-15 2019-11-15 Multi-axial fatigue vibration rack for rail vehicle

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110749461A (en) * 2019-11-15 2020-02-04 西南交通大学 Multi-axial fatigue vibration rack for rail vehicle

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110749461A (en) * 2019-11-15 2020-02-04 西南交通大学 Multi-axial fatigue vibration rack for rail vehicle
CN110749461B (en) * 2019-11-15 2024-03-26 西南交通大学 Multi-shaft fatigue vibration rack for railway vehicle

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