CN212722435U - Normal load loading device based on single-shaft fatigue testing machine - Google Patents

Normal load loading device based on single-shaft fatigue testing machine Download PDF

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Publication number
CN212722435U
CN212722435U CN202021265728.4U CN202021265728U CN212722435U CN 212722435 U CN212722435 U CN 212722435U CN 202021265728 U CN202021265728 U CN 202021265728U CN 212722435 U CN212722435 U CN 212722435U
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China
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normal
partition plate
testing machine
fixing
normal load
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CN202021265728.4U
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Chinese (zh)
Inventor
孔晨浩
平学成
曾鑫
叶凡炜
宋淮桐
张潇
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Tianjin University of Science and Technology
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Tianjin University of Science and Technology
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Abstract

The utility model relates to a normal load loading device based on unipolar fatigue testing machine, its characterized in that: the device comprises a normal load loading unit and a normal fixing unit, wherein the normal load loading unit comprises a test piece, a micro-motion gasket clamping slide block, a first cover plate, a second cover plate, a workbench, a force measuring sensor and a normal load adjusting bolt; the normal direction fixing unit comprises a first partition plate, a second partition plate, a fixing screw rod, a limiting nut, a fixing nut, a locknut, a first normal direction fixing piece and a second normal direction fixing piece. The utility model has scientific and reasonable structural design, simple and ingenious device structure, balanced load loading and fixed loading load, and can be well applied to actual complex conditions to ensure the test precision; and the test piece is loaded in balance, so that the accuracy of the test result is ensured.

Description

Normal load loading device based on single-shaft fatigue testing machine
Technical Field
The utility model belongs to material performance test field relates to unipolar fatigue testing machine loading device, in particular to normal load loading device based on unipolar fatigue testing machine.
Background
Fretting fatigue refers to a phenomenon that a part of a surface slides relatively with other contact surfaces with small amplitude under the action of cyclic load, so that the fatigue strength of the part is reduced or the part is broken early, and the fretting is slight and unpredictable and eliminated, can happen on most mechanical structures such as screw connection, key connection and some interference fit pieces, and can accelerate parts and reduce the service life due to fretting fatigue in the fields of mechanical engineering, aerospace, biomedical treatment and the like. Therefore, the research on the aspects of estimating the fatigue life of the material and detecting the fatigue strength of the material has important significance. And when the fretting fatigue test is carried out, the fretting pad compresses the test piece along the normal direction. In the fretting fatigue test process, the test piece bears an axial force (fatigue load), and the fretting pads on two sides are pressed on the surface of the fretting test piece under the action of a normal force. Due to the effect of fatigue load, micron-scale relative sliding can occur between the test piece and the micro-pad, a micro-motion phenomenon is generated, and finally micro-motion fatigue failure occurs in the contact area of the test piece and the micro-pad, so that how to realize the reliability and the practicability of normal load and simulating a real use scene plays a crucial role in research on micro-motion fatigue.
Through the search of the published patent documents, the following similar published patent documents are found:
1. CN204988981U discloses a simple manual fretting fatigue loading device, which forms a stable integral frame through a baffle and a support column, wherein the outer side wall of the lower part of the baffle is provided with a first connecting rod support lug, and a push rod mounting hole, a long lever support lug and a pawl support lug are sequentially arranged above the first connecting rod support lug along the vertical direction; the long lever is approximately L-shaped, a weight is hung at the end of the long arm, the end of the short arm is hinged with the connecting rod group, the turning point is hinged with the long lever supporting lug, a ratchet wheel is arranged outside the turning point, and the ratchet wheel is matched with the stopping pawl; the connecting rod group is hinged with the push rods, one end of the inner side of each push rod is provided with a force sensor, the other end of each force sensor is connected with the micro-motion pad, and a sample is arranged between the two push rods. The utility model discloses an operation is simple and easy, can manual regulation and control the gravity of weight and then realize the control to the loading power.
2. CN105043976A discloses a friction coefficient measurement subassembly among test device of fretting vice friction coefficient among dynamic measurement fretting fatigue in-process realizes the fretting operating mode and dynamic measurement fretting fatigue in-process test piece the fretting section and the fretting pad cooperate the friction coefficient between the fretting vice that forms, and application of horizontal direction load is realized to normal force loading subassembly, and the fixed subassembly of upper end realizes that test piece and anchor clamps are specific fixed. The horizontal loading of the fretting fatigue test is realized by adopting a hydraulic system, the loading system adopts a closed force system frame structure, and a piston rod of a hydraulic cylinder pushes a fretting pad clamping slide block to move in a slide groove of a clamp body. The friction coefficient measuring component is fixed on the upper end fixing component through a pin, in the vertical direction, the friction coefficient measuring component is only subjected to friction force generated between the test piece and the micromotion pad due to the micromotion effect except for self gravity and the gravity of the hydraulic cylinder, and the friction coefficient of the micromotion pair in the micromotion fatigue test process can be dynamically monitored after the friction coefficient measuring component is calibrated by pasting a strain gauge on the working section of the clamp body.
3. CN110132739A discloses a fretting fatigue test normal load loading device and method. The loading device consists of two parts: a fixed portion and a load-carrying portion. The method specifically comprises the following steps: the clamp comprises a micro-motion pad, a first clamping plate, a second clamping plate, a force measuring sensor, a load adjusting screw, a locknut, a limiting screw rod, a positioning nut, a limiting nut, a bushing, a fixing plate, a fixing bolt, an inner side fixing block and an outer side fixing block. The utility model discloses a realized developing fine motion fatigue test on ordinary fatigue testing machine.
The normal force loading device that present cooperation unipolar fatigue testing machine carried out fine motion fatigue test has utilizes hydraulic means to realize, does so not only to make whole device structure complicated, can increase experimental apparatus's weight moreover, causes certain influence to the precision of unipolar fatigue testing machine originally, makes use cost increase moreover to some extent. Meanwhile, the control of the normal load acting force by using a hydraulic device is not accurate enough.
The conventional loading device for realizing the normal force still utilizes a single power source, so that the normal load borne by the test piece is unbalanced, additional factors except the experiment are generated, the experiment result is influenced, and the experiment conclusion is not accurate enough. The normal load loading device used at present can not well control loads on two sides to be consistent, and the loads are fixed, so that the complex conditions in actual use can not be well simulated, and the precision of an experimental result is influenced to a certain extent.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to prior art's defect and not enough, provide a normal direction loading device based on unipolar fatigue testing machine, it is heavy to solve normal direction loading device among the prior art, and is with high costs, can not accurate control load size scheduling problem.
The utility model provides a its technical problem realize through following technical scheme:
the utility model provides a normal load loading device based on unipolar fatigue testing machine which characterized in that: the device comprises a normal load loading unit and a normal fixing unit, wherein the normal load loading unit comprises a test piece, a micro-motion gasket clamping slide block, a first cover plate, a second cover plate, a workbench, a force measuring sensor and a normal load adjusting bolt; the normal fixing unit comprises a first partition plate, a second partition plate, a fixing screw, a limiting nut, a fixing nut, a locknut, a first normal fixing piece and a second normal fixing piece;
the micro-motion gasket is placed at the vacant position of the first cover plate and covers the micro-motion gasket clamping slide block, a gasket clamp is fixedly combined through an inner hexagon bolt, the gasket clamp is symmetrically installed in through grooves on the left side and the right side of the workbench, the force measuring sensors are symmetrically installed and placed in the through grooves, the inner sides of the force measuring sensors are in contact with the gasket clamp, and the second cover plate is fixed on the upper surface of the workbench through the inner hexagon bolt; the test piece penetrates through the through hole of the workbench from top to bottom, the lower end of the test piece is fixedly connected with the bottom fixing piece at the bottom end of the workbench, and the upper end of the test piece is connected with the single-shaft fatigue testing machine through the through hole arranged on the test piece;
the first partition plate is fixed at a step of the workbench through a limiting nut, the normal load adjusting bolt passes through a threaded hole in the center of the first partition plate to be in contact with the force measuring sensor, through holes are formed in four corners of the first partition plate and the second partition plate, fixing screws can pass through the through holes, the first normal fixing piece and the second normal fixing piece are connected through bolts and fixed with stand columns on two sides of the single-axis fatigue testing machine, and the first normal fixing piece is connected with the second partition plate through the screws and clamped with the second partition plate through the fixing nut and the anti-loosening nut; the second partition plate is fixed on the fixing screw rod through a limiting nut.
And the micro gasket is clamped and arranged on the first cover plate and can be replaced.
And a second strain gauge is adhered to the axial surface of the test piece.
Moreover, first strain gauges are symmetrically attached to the left and right sides of the hanging part at the lower end of the workbench.
Moreover, the front end face and the rear end face of the workbench are provided with observation holes.
And a threaded hole is formed in the step part connected to the bottom end of the workbench, a threaded hole is also formed in the position corresponding to the first partition plate, and the workbench and the first partition plate are fixed through bolts penetrating through the threaded holes.
The utility model discloses an advantage and beneficial effect do:
1. the utility model discloses a normal direction load loading device based on unipolar fatigue testing machine adopts the bolt to apply great normal direction load to the test piece, simple structure, and convenient operation can fix on unipolar fatigue testing machine, and the practicality is strong.
2. The utility model discloses a normal load loading device based on unipolar fatigue testing machine, the fine motion gasket clamp set up in on the first apron and removable, the fine motion gasket through changing different materials realizes the vice form of different fine motions.
3. The utility model discloses a normal direction load loading device based on unipolar fatigue testing machine, the workstation leads to the inslot and installs force cell sensor, but the normal direction load situation of change of real time monitoring to regulate and control it, guarantee normal direction load stability, simulate the actual load condition.
4. The utility model discloses a normal load loading device based on unipolar fatigue testing machine, test piece axial surface paste have the second foil gage, can carry out real time monitoring to the axial force of applying on the work piece, detect whether the axial load changes and accord with expectation to finely tune according to the deviation, improve the whole availability factor of device, make the experimental result more comprehensive, accurate.
5. The utility model discloses a normal load loading device based on unipolar fatigue testing machine, the left and right symmetry is pasted first foil gage on the workstation lower extreme linkage, the coefficient of friction of measurable quantity play test piece.
6. The utility model discloses a normal load loading device based on unipolar fatigue testing machine, the terminal surface all is equipped with the observation hole around the workstation, can observe the fracture condition of workpiece surface among the fatigue test.
7. The utility model discloses a normal load loading device based on unipolar fatigue testing machine, the terminal surface is opened under the work step ladder department has work step ladder screw hole and with bolted connection for the first baffle, guarantees that the installation of workstation axial is stable.
8. The utility model has scientific and reasonable structural design, simple and ingenious device structure, balanced load loading and fixed loading load, and can be well applied to actual complex conditions to ensure the test precision; and the test piece is loaded in balance, so that the accuracy of the test result is ensured.
Drawings
Fig. 1 is a schematic structural diagram of the present invention;
FIG. 2 is a schematic structural view of the micro spacer clamping slider of the present invention;
FIG. 3 is a schematic structural view of the micro-motion spacer of the present invention;
fig. 4 is a schematic structural view of a second cover plate of the present invention;
FIG. 5 is a schematic view of the gasket holder of the present invention;
FIG. 6 is a schematic view of the load cell of the present invention;
fig. 7 is an isometric view and a top-bottom isometric view of the table of the present invention.
Description of the reference numerals
1-test piece, 2-micro-motion gasket, 3-micro-motion gasket clamping slide block, 4-first cover plate, 5-second cover plate, 6-workbench, 7-force transducer, 8-normal load adjusting bolt, 9-first clapboard, 10-second clapboard, 11-fixing screw, 12-limiting nut, 13-fixing nut, 14-locknut, 15-first normal fixing piece, 16-second normal fixing piece, 17-bottom fixing piece, 18-gasket clamp, 19-observation hole, 20-first strain gauge, 21-second strain gauge and 22-working step threaded hole.
Detailed Description
The present invention will be described in further detail with reference to specific examples, which are provided for illustrative purposes only, and are not intended to be limiting, and the scope of the present invention should not be limited thereby.
The utility model provides a normal load loading device based on unipolar fatigue testing machine which characterized in that: the device comprises a normal load loading unit and a normal fixing unit, wherein the normal load loading unit comprises a test piece 1, a micro-motion gasket 2, a micro-motion gasket clamping slide block 3, a first cover plate 4, a second cover plate 5, a workbench 6, a force measuring sensor 7 and a normal load adjusting bolt 8; the normal direction fixing unit comprises a first clapboard 9, a second clapboard 10, a fixing screw rod 11, a limiting nut 12, a fixing nut 13, a locknut 14, a first normal direction fixing piece 15 and a second normal direction fixing piece 16;
a micro-motion gasket is placed at the vacant position of the first cover plate and covers the micro-motion gasket clamping slide block, a gasket clamp 18 is fixedly combined through an inner hexagon bolt, the gasket clamp is symmetrically installed in through grooves on the left side and the right side of the workbench, the force measuring sensors are symmetrically installed and placed in the through grooves, the inner sides of the force measuring sensors are in contact with the gasket clamp, and the second cover plate is fixed on the upper surface of the workbench through the inner hexagon bolt; the test piece penetrates through the through hole of the workbench from top to bottom, the bottom end fixing piece 17 at the bottom end of the workbench is fixedly connected at the lower end, and the upper end of the test piece is connected with the single-shaft fatigue testing machine through the through hole arranged on the test piece;
the first partition plate is fixed at a step of the workbench through a limiting nut, the normal load adjusting bolt passes through a threaded hole in the center of the first partition plate to be in contact with the force measuring sensor, through holes are formed in four corners of the first partition plate and the second partition plate, fixing screws can pass through the through holes, the first normal fixing piece and the second normal fixing piece are connected through bolts and fixed with stand columns on two sides of the single-axis fatigue testing machine, and the first normal fixing piece is connected with the second partition plate through the screws and clamped with the second partition plate through the fixing nut and the anti-loosening nut; the second partition plate is fixed on the fixing screw rod through a limiting nut.
The utility model adopts the bolt to apply larger normal load to the test piece, has simple structure and convenient operation, can be fixed on a single-shaft fatigue testing machine, and has strong practicability; a force measuring sensor is arranged in the through groove of the workbench, so that the normal load change condition can be monitored in real time and regulated, the stability of the normal load is ensured, and the actual load condition is simulated.
The micro gasket is clamped and arranged on the first cover plate and can be replaced, and different micro pair forms are realized by replacing micro gaskets made of different materials.
The axial surface of the test piece is pasted with the second strain gauge 21, so that the axial force applied to the workpiece can be monitored in real time, and whether the change of the axial load is expected or not is detected, so that fine adjustment is performed according to deviation, the integral use efficiency of the device is improved, and the experimental result is more comprehensive and accurate.
The first strain gauges 20 are symmetrically attached to the left and right sides of the hanging part at the lower end of the workbench, and friction coefficients of a test piece can be measured.
The front end face and the rear end face of the workbench are provided with observation holes 19, so that the fracture condition of the surface of the workpiece in the fatigue test can be observed.
The lower end face of the working step ladder is provided with a working step ladder threaded hole 22 and is connected with the first partition plate through a bolt, so that the axial installation stability of the workbench is ensured.
The utility model discloses a theory of operation does:
when the loading device works, the first normal fixing piece and the second normal fixing piece are connected through bolts and fixed on the stand columns on two sides of the single-shaft fatigue testing machine, the approximate axial position of the whole loading device is determined, and the loading device is subjected to fine adjustment after the normal fixing is finished; and then the second clapboard is fixed on the screw rod extending out of the first method phase fixing piece through the fixing nut and the locknut.
After the fixture part in the middle is assembled after the fixture part is fixed, firstly, the micro-motion gasket is clamped at the groove of the first cover plate, then the first cover plate and the micro-motion gasket clamping slide block are connected together by utilizing the hexagon socket head cap screws, after the gasket fixture is assembled, the gasket fixture is respectively placed in the through grooves which are bilaterally symmetrical on the workbench, meanwhile, the force measuring sensor is placed outside the gasket fixture, the probe of the force measuring sensor is in direct contact with the gasket fixture, and finally, the second cover plate is fixed with the upper surface of the workbench together by utilizing the hexagon socket head cap screws.
The test piece top-down passes the through-hole of workstation, opens threaded hole on the bottom mounting, utilizes bolt and nut to be in the same place bottom mounting and the portion of hanging and the test piece of workstation below fixed, and rethread fixed part's screw hole is with bottom mounting and unipolar fatigue testing machine fixed connection, and the top is connected with unipolar fatigue testing machine through-hole and the unipolar fatigue testing machine of test piece equally, and this moment axial fixity finishes.
Screwing a normal load adjusting bolt on the first partition plate, simultaneously respectively penetrating a fixing screw rod through the first partition plate and the second partition plate which are bilaterally symmetrical, adjusting the axial position of the whole normal fixing device by adjusting the bolt on the second normal fixing piece, enabling the first partition plate to be clamped at the step of the workbench, after fine adjustment is finished, respectively realizing normal positioning on the two partition plates by utilizing a limiting nut, and simultaneously fixing the workbench and the first partition plate together by utilizing the bolt to ensure the axial stability of the workbench.
The utility model discloses can carry out concrete control and accurate the regulation to axial load, because the test piece surface paste has the foil gage, can reflect the situation of change of axial load in real time, finely tune axial load according to the observation data, make its situation of change that accords with expectations more, the more accurate simulation in service behavior. Meanwhile, a load cell is also arranged in the normal direction, so that the stability of the normal load can be ensured.
Although the embodiments of the present invention and the accompanying drawings are disclosed for illustrative purposes, those skilled in the art will appreciate that: various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims, and therefore, the scope of the present invention is not limited to the disclosure of the embodiments and the accompanying drawings.

Claims (6)

1. The utility model provides a normal load loading device based on unipolar fatigue testing machine which characterized in that: the device comprises a normal load loading unit and a normal fixing unit, wherein the normal load loading unit comprises a test piece, a micro-motion gasket clamping slide block, a first cover plate, a second cover plate, a workbench, a force measuring sensor and a normal load adjusting bolt; the normal fixing unit comprises a first partition plate, a second partition plate, a fixing screw, a limiting nut, a fixing nut, a locknut, a first normal fixing piece and a second normal fixing piece;
the micro-motion gasket is placed at the vacant position of the first cover plate and covers the micro-motion gasket clamping slide block, a gasket clamp is fixedly combined through an inner hexagon bolt, the gasket clamp is symmetrically installed in through grooves on the left side and the right side of the workbench, the force measuring sensors are symmetrically installed and placed in the through grooves, the inner sides of the force measuring sensors are in contact with the gasket clamp, and the second cover plate is fixed on the upper surface of the workbench through the inner hexagon bolt; the test piece penetrates through the through hole of the workbench from top to bottom, the lower end of the test piece is fixedly connected with the bottom fixing piece at the bottom end of the workbench, and the upper end of the test piece is connected with the single-shaft fatigue testing machine through the through hole arranged on the test piece;
the first partition plate is fixed at a step of the workbench through a limiting nut, the normal load adjusting bolt passes through a threaded hole in the center of the first partition plate to be in contact with the force measuring sensor, through holes are formed in four corners of the first partition plate and the second partition plate, fixing screws can pass through the through holes, the first normal fixing piece and the second normal fixing piece are connected through bolts and fixed with stand columns on two sides of the single-axis fatigue testing machine, and the first normal fixing piece is connected with the second partition plate through the screws and clamped with the second partition plate through the fixing nut and the anti-loosening nut; the second partition plate is fixed on the fixing screw rod through a limiting nut.
2. The normal load loading device based on the uniaxial fatigue testing machine according to claim 1, wherein: the micro gasket is arranged on the first cover plate in a clamping mode and can be replaced.
3. The normal load loading device based on the uniaxial fatigue testing machine according to claim 1, wherein: and a second strain gauge is stuck to the axial surface of the test piece.
4. The normal load loading device based on the uniaxial fatigue testing machine according to claim 1, wherein: first strain gauges are symmetrically attached to the left side and the right side of the hanging part at the lower end of the workbench.
5. The normal load loading device based on the uniaxial fatigue testing machine according to claim 1, wherein: the front end face and the rear end face of the workbench are provided with observation holes.
6. The normal load loading device based on the uniaxial fatigue testing machine according to claim 1, wherein: the working platform is characterized in that a working step ladder threaded hole is formed in the lower end face ladder position of the working platform, a threaded hole is formed in the position corresponding to the first partition plate, and the working platform and the first partition plate are fixed through bolts penetrating the threaded hole.
CN202021265728.4U 2020-07-02 2020-07-02 Normal load loading device based on single-shaft fatigue testing machine Expired - Fee Related CN212722435U (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111650063A (en) * 2020-07-02 2020-09-11 天津科技大学 Normal load loading device based on single-shaft fatigue testing machine

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111650063A (en) * 2020-07-02 2020-09-11 天津科技大学 Normal load loading device based on single-shaft fatigue testing machine

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