CN105806698A - Energy-absorption buffering device for Hopkinson pressure bar - Google Patents
Energy-absorption buffering device for Hopkinson pressure bar Download PDFInfo
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- CN105806698A CN105806698A CN201610132879.4A CN201610132879A CN105806698A CN 105806698 A CN105806698 A CN 105806698A CN 201610132879 A CN201610132879 A CN 201610132879A CN 105806698 A CN105806698 A CN 105806698A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
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Abstract
The invention relates to an energy-absorption buffering device for a Hopkinson pressure bar. An energy-absorption rod passes through a through hole in an end cover at one end of a buffer cylinder, an energy-absorption rod base at one end of the energy-absorption rod can be located in a cylinder body of the buffer cylinder, and a pressure-bearing head at the other end of the energy-absorption rod can be located outside the cylinder body; 5-12 reset springs are located in the cylinder body of the buffer cylinder, and two ends of each reset spring are fixed at the outer end surface of the energy-absorption rod base and the inner wall of the buffer cylinder, respectively; a connecting rod of the energy-absorption rod is sleeved with a flexible gasket, the flexible gasket is located between the inner wall of the cylinder body at one end, provided with the through hole, of the buffer cylinder and the inner end surface of the energy-absorption rod base; an elastic buffer cushion block is embedded into the end surface of the pressure-bearing head; and 8-16 ball sliding rails are uniformly distributed on the inner circumferential surface of the buffer cylinder in an annular manner, and each ball sliding rail is parallel to the central line of the buffer cylinder. According to the energy-absorption buffering device, the maximum kinetic energy which can be absorbed by the energy-absorption buffering device can be quantified without exceeding the ranges of the springs and damaging the buffer gasket, thereby providing references for the specific implementation of a Hopkinson pressure bar experiment.
Description
Technical field
The present invention relates to ballistics experiment field, specifically a kind of energy-absorbing buffer device for Hopkinson pressure bar experiment.
Background technology
Split hopkinson press bar (SHPB) is one of the most frequently used testing equipment of current research material dynamic mechanical characteristic, is mainly made up of discharger, bullet, incident bar, transmission bar, energy-absorbing buffer device and the part such as strain, bullet speed test instrunment.Existing Hopkinson pressure bar energy absorption device, it is absorb impact kinetic energy by air damper and cushion pad and cushion the shock of transmission bar mostly, for instance major diameter split hopkinson press bar patent (No.200620031882.9) of No. Three Engineering Corps Research Institute of PLA General Staff's application and Hopkinson pressure bar adjustable air antivibrator patent (No.201310150651.4) of Harbin Engineering University's application.2 deficiencies of existing correlation technique ubiquity: 1) after Hopkinson pressure bar experiment terminates each time, once it is required for manually making energy-absorbing bar reset before experiment on starting, this can cause the decline of certain consuming time and efficiency；2) the absorbent maximum impact kinetic energy of institute not being carried out necessary quantization when design energy-absorbing buffer device, this can make experimenter cannot reasonably estimate the upper limit, thus increasing the danger coefficient of experiment.
Summary of the invention
In order to overcome the energy-absorbing bar existed in existing Hopkinson pressure bar energy-absorbing buffer device to need each hand-reset, and the maximum kinetic energy that absorbs of device can not being carried out quantification problem, the present invention proposes a kind of Hopkinson pressure bar energy-absorbing buffer device.
The present invention includes elastic buffer cushion block, pressure bearing head, energy-absorbing bar, cushion dashpot, flexible gaskets, energy-absorbing bar base, ball slide rail, back-moving spring and bearing.Wherein:
Described cushion dashpot is placed on bearing；Energy-absorbing bar, through the through hole on the end cap of described cushion dashpot one end, makes the energy-absorbing bar base of this energy-absorbing bar one end be positioned at the cylinder body of described cushion dashpot, makes the pressure bearing head of this energy-absorbing bar other end be positioned at outside the cylinder body of described cushion dashpot.5～13 back-moving springs are positioned at the cylinder body of described cushion dashpot, and make one end of each back-moving spring be fixed on the outer face of energy-absorbing bar base, make the other end of each back-moving spring be fixed on the inwall of the described cushion dashpot other end.
Flexible gaskets is sleeved on the connecting rod of described energy-absorbing bar, and in the cylinder body of cushion dashpot, be between the inner face that this cushion dashpot has through hole one end inboard wall of cylinder block and energy-absorbing bar base.Elastic buffer cushion block is inlaid in the end face of described pressure bearing head.Article 8～16, ball slide rail is distributed on the inner circumferential surface of described cushion dashpot ringwise, and makes the centerline parallel of each ball slide rail and cushion dashpot.
Described energy-absorbing bar is divided into three parts: one end is pressure bearing head, and the other end is energy-absorbing bar base, and the part connecting described pressure bearing head and energy-absorbing bar base is connecting rod.There is the groove for installing elastic buffer cushion block at the center of described pressure bearing head end face.The external diameter of described energy-absorbing bar base is identical with the internal diameter of described ball slide rail, and makes to be slidably matched between the two.
In described each back-moving spring, the axis of a back-moving spring overlaps with the straight line of described cushion dashpot, and all the other each back-moving springs are distributed on the surrounding of the back-moving spring being positioned at cushion dashpot center.
The present invention be one can automatically reset novel Hopkinson pressure bar energy-absorbing buffer device, including energy-absorbing bar, cushion dashpot, back-moving spring and buffer gasket.
Described energy-absorbing bar is divided into pressure bearing head, connecting rod and base three part, wherein the embedded elastic buffer cushion block of pressure bearing head, and pressure bearing head is connected by connecting rod with base, and base is then connected with back-moving spring, and the other end of back-moving spring is connected with cushion dashpot right-hand member.Described cushion dashpot left end leaves circular hole, and the shaft portion being available for energy-absorbing bar horizontally slips, and is provided with looped flexible packing ring, is provided with 8～16 ball slide rails between energy-absorbing bar base and cushion dashpot inwall between cushion dashpot left end and energy-absorbing bar base.Acquiescence experiment loading direction is from left to right.Additionally, cushion dashpot side is provided with some pores, but only for aerofluxus, use not as air damper.
The maximum quantization method absorbing kinetic energy of described energy-absorbing buffer device, realizes by Theoretical Calculation and in conjunction with computer simulation, and need physical quantity taken into consideration includes: 1) the total quality M and bulk velocity V of energy-absorbing bar；2) the coefficient of elasticity K of back-moving spring, quantity N, length L and maximum compressible ratio P1；3) elastic modulus E of annular resilient buffer gasket, width H and maximum compressible ratio P2.Acquired has the technical effect that, less than spring range, (namely compression distance is less than L × P1) do not damage buffer gasket (namely compression distance is less than H × P simultaneously2) when, quantify the absorbent maximum kinetic energy of the present invention, thus for Hopkinson pressure bar experiment be embodied as offer reference, detailed quantization method sees below detailed description of the invention.
Accompanying drawing explanation
Fig. 1 is the structural principle schematic diagram of the present invention.
Fig. 2 is the a-a direction view of the present invention.
Fig. 3 is the b-b direction view of the present invention.In figure:
1. elastic buffer cushion block；2. pressure bearing head；3. energy-absorbing bar；4. cushion dashpot；5. looped flexible packing ring；6. energy-absorbing bar base；7. ball slide rail；8. back-moving spring；9. bearing.
Detailed description of the invention
The purpose of the present embodiment is in that to provide the one can automatically reset Hopkinson pressure bar energy-absorbing buffer device, to solve the problem that Hopkinson pressure bar device of the prior art needs manually energy-absorbing bar to be resetted, and the maximum kinetic energy that absorbs is quantified, thus improving conventional efficient, and provide reference for experimental design.
Described Hopkinson pressure bar energy-absorbing buffer device includes elastic buffer cushion block 1, pressure bearing head 2, energy-absorbing bar 3, cushion dashpot 4, looped flexible packing ring 5,6. energy-absorbing bar base, ball slide rail 7, back-moving spring 8 and bearing 9.
Described cushion dashpot 4 is placed on bearing 9；This cushion dashpot is the cylindrical member closed, and has and the through hole of energy-absorbing bar 3 matched in clearance on the end cap of this cushion dashpot one end.Energy-absorbing bar 3, through described through hole, makes the energy-absorbing bar base 6 of this energy-absorbing bar one end be positioned at the cylinder body of described cushion dashpot 4, makes the pressure bearing head 2 of this energy-absorbing bar other end be positioned at outside this cylinder body.5～13 back-moving springs 8 are positioned at the cylinder body of described cushion dashpot, and make one end of each back-moving spring be fixed on the outer face of energy-absorbing bar base of described energy-absorbing bar, make the other end of each back-moving spring be fixed on the inwall of the described cushion dashpot other end.In described each back-moving spring, the axis of a back-moving spring overlaps with the straight line of described cushion dashpot, and remaining back-moving spring is distributed on the surrounding of the back-moving spring being positioned at cushion dashpot center.In the present embodiment, the quantity of back-moving spring 8 is 5.
Flexible gaskets 5 is ring-type, is sleeved on the connecting rod of described energy-absorbing bar, and in the cylinder body of cushion dashpot, be between the inner face that this cushion dashpot has through hole one end inboard wall of cylinder block and energy-absorbing bar base 6.Elastic buffer cushion block 1 is inlaid in the end face of described pressure bearing head 2.Article 8～16, ball slide rail is distributed on the inner circumferential surface of described cushion dashpot ringwise, and makes the centerline parallel of each ball slide rail and cushion dashpot.In the present embodiment, the quantity of described ball slide rail is 10.
Described energy-absorbing bar 3 is circular rod-shaped, is divided into three parts: one end is pressure bearing head 2, and the other end is energy-absorbing bar base 6, and the part connecting described pressure bearing head and energy-absorbing bar base is connecting rod.There is the groove for installing elastic buffer cushion block 1 at the center of described pressure bearing head 2 end face.The external diameter of described energy-absorbing bar base 6 is identical with the internal diameter of described ball slide rail 7, and makes to be slidably matched between the two.
In Hopkinson pressure bar experiment, when the pressure bearing head 2 of transmission bar impact energy absorption bar, impact kinetic energy has been carried out first time buffering by the embedded elastic buffer cushion block 1 of pressure bearing head, is subsequently converted to the kinetic energy K that energy-absorbing bar is overalla；Described kinetic energy KaThe i.e. index of follow-up requirement.Energy-absorbing bar base 6 in cushion dashpot 4 is slided to the blind end of this cushion dashpot by ball slide rail 7, makes the back-moving spring 8 being in free state produce compression simultaneously.The effect of ball slide rail 7 is to reduce energy-absorbing bar base frictional resistance in moving process so that back-moving spring 8 becomes the main body absorbing kinetic energy, thus increasing the maximum credibility absorbing kinetic energy of quantization.After impact kinetic energy is fully converted to the elastic potential energy of back-moving spring 8; back-moving spring 8 starts to rebound to the other end; and absorb energy by the flexible gaskets 5 between cushion dashpot 4 and energy-absorbing bar base 6, and play a protective role, too quickly with the bounce-back preventing back-moving spring 8.This is because under effect of inertia, back-moving spring 8 still can move a segment distance again after bounce-back to free state to flexible gaskets 5 one end, now energy-absorbing bar base 6 compresses ring-type flexible gaskets 5, this portion of residual kinetic energy is converted into the elastic potential energy of packing ring, within a short period of time, back-moving spring 8 was stable at initial position again, namely affranchise state, thus ready for testing next time.
It is as follows that this energy-absorbing buffer device maximum absorbs kinetic energy quantification manner:
First, according to law of conservation of energy it can be seen that when energy-absorbing bar bulk velocity reduces to 0, the kinetic energy of energy-absorbing bar is fully converted to the elastic potential energy of back-moving spring 8.In theory, when back-moving spring 8 is compressed to extreme position, i.e. △ x=P1During L, the energy-absorbing bar kinetic energy absorbed is maximum Ka Max.Meanwhile, in order to protect ring-type flexible gaskets 5, after back-moving spring 8 bounce-back, the distance △ y beyond free state is not to be exceeded P2H.To sum up, the maximum kinetic energy that absorbs obtained according to Theoretical Calculation can be expressed as:
△x≤P1×L(2)
△y≤P2×H(3)
In formula (1)～(3): Ka MaxMaximum for energy-absorbing bar kinetic energy；The total quality of M and V respectively energy-absorbing bar and bulk velocity；K, N, L, P1It is followed successively by the coefficient of elasticity of back-moving spring, quantity, length and maximum compressible ratio；H, P2The respectively width of annular resilient buffer gasket and maximum compressible ratio；Beyond the distance of free state after distance that △ x, △ y respectively back-moving spring is compressed and back-moving spring bounce-back.
Based on the Numerical Simulation of dynamic impulsion, calculated value being verified, simulation result shows that the error of calculated value is within 0.8%, therefore the maximum kinetic energy that absorbs of the present invention is:
Corresponding energy-absorbing bar bulk velocity maximum is:
In formula (4) and (5): VMaxRepresenting the maximum of energy-absorbing bar bulk velocity, all the other parameter meanings are identical with formula (1)～(3).
It has been experienced that; the present embodiment can pass through repeatedly examination and beat the relation set up between bullet bullet speed or transmitting air pressure and energy-absorbing bar bulk velocity; thereby through the maximum kinetic energy that absorbs to retrain maximum bullet bullet speed or to launch air pressure, to play Protection device, reduce the effect of danger coefficient.
Claims (3)
1. a Hopkinson pressure bar energy-absorbing buffer device, it is characterised in that include elastic buffer cushion block, pressure bearing head, energy-absorbing bar, cushion dashpot, flexible gaskets, energy-absorbing bar base, ball slide rail, back-moving spring and bearing；Wherein:
Energy-absorbing bar, through the through hole on the end cap of described cushion dashpot one end, makes the energy-absorbing bar base of this energy-absorbing bar one end be positioned at the cylinder body of described cushion dashpot, makes the pressure bearing head of this energy-absorbing bar other end be positioned at outside the cylinder body of described cushion dashpot；5～13 back-moving springs are positioned at the cylinder body of described cushion dashpot, and make one end of each back-moving spring be fixed on the outer face of energy-absorbing bar base, make the other end of each back-moving spring be fixed on the inwall of the described cushion dashpot other end；
Flexible gaskets is sleeved on the connecting rod of described energy-absorbing bar, and in the cylinder body of cushion dashpot, be between the inner face that this cushion dashpot has through hole one end inboard wall of cylinder block and energy-absorbing bar base；Elastic buffer cushion block is inlaid in the end face of described pressure bearing head；Article 8～16, ball slide rail is distributed on the inner circumferential surface of described cushion dashpot ringwise, and makes the centerline parallel of each ball slide rail and cushion dashpot.
2. Hopkinson pressure bar energy-absorbing buffer device as claimed in claim 1, it is characterised in that described energy-absorbing bar is divided into three parts: one end is pressure bearing head, and the other end is energy-absorbing bar base, and the part connecting described pressure bearing head and energy-absorbing bar base is connecting rod；There is the groove for installing elastic buffer cushion block at the center of described pressure bearing head end face；The external diameter of described energy-absorbing bar base is identical with the internal diameter of described ball slide rail, and makes to be slidably matched between the two.
3. Hopkinson pressure bar energy-absorbing buffer device as claimed in claim 1, it is characterized in that, in described each back-moving spring, the axis of a back-moving spring overlaps with the straight line of described cushion dashpot, and all the other each back-moving springs are distributed on the surrounding of the back-moving spring being positioned at cushion dashpot center.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610132879.4A CN105806698A (en) | 2016-03-09 | 2016-03-09 | Energy-absorption buffering device for Hopkinson pressure bar |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610132879.4A CN105806698A (en) | 2016-03-09 | 2016-03-09 | Energy-absorption buffering device for Hopkinson pressure bar |
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| CN105806698A true CN105806698A (en) | 2016-07-27 |
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| CN201610132879.4A Pending CN105806698A (en) | 2016-03-09 | 2016-03-09 | Energy-absorption buffering device for Hopkinson pressure bar |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106122332A (en) * | 2016-08-31 | 2016-11-16 | 哈尔滨工程大学 | Hopkinson pressure bar electromagnetic buffer energy absorption device |
| CN107037578A (en) * | 2017-06-12 | 2017-08-11 | 张素平 | A kind of adjustable for height light microscope base |
| CN107703009A (en) * | 2017-10-27 | 2018-02-16 | 河海大学 | A kind of magnetic induction for SHPB experiments is tested the speed and anti-incident bar recoiling device |
| CN109323937A (en) * | 2018-11-23 | 2019-02-12 | 浙江大学 | A kind of Hopkinson pressure bar damping unit |
| CN111071735A (en) * | 2019-12-31 | 2020-04-28 | 中冶北方（大连）工程技术有限公司 | Power frequency transmission adhesive tape running and slipping detection device and detection method |
| CN111071733A (en) * | 2019-12-31 | 2020-04-28 | 中冶北方（大连）工程技术有限公司 | Pneumatic device and method for detecting running and breakage of adhesive tape |
| CN111562178A (en) * | 2020-06-28 | 2020-08-21 | 天津大学 | Dynamic tensile test device with kinetic energy absorption and test method |
| CN113607545A (en) * | 2021-08-17 | 2021-11-05 | 西北工业大学 | Single pulse separation type Hopkinson pull rod experiment device based on electromagnetic force loading |
| CN114026404A (en) * | 2019-03-28 | 2022-02-08 | 伊利诺斯工具制品有限公司 | Collision mitigation device and material testing system with collision mitigation device |
| CN117470639A (en) * | 2023-12-22 | 2024-01-30 | 深圳大学 | Energy absorption buffer device and method applied to dynamic true triaxial electromagnetic Hopkinson bar |
| CN118168962A (en) * | 2024-05-14 | 2024-06-11 | 四川大学 | Single-pulse experimental device and experimental method based on Hopkinson pressure bar |
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2016
- 2016-03-09 CN CN201610132879.4A patent/CN105806698A/en active Pending
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106122332A (en) * | 2016-08-31 | 2016-11-16 | 哈尔滨工程大学 | Hopkinson pressure bar electromagnetic buffer energy absorption device |
| CN107037578A (en) * | 2017-06-12 | 2017-08-11 | 张素平 | A kind of adjustable for height light microscope base |
| CN107703009A (en) * | 2017-10-27 | 2018-02-16 | 河海大学 | A kind of magnetic induction for SHPB experiments is tested the speed and anti-incident bar recoiling device |
| CN107703009B (en) * | 2017-10-27 | 2020-05-05 | 河海大学 | Magnetic induction speed measurement and anti-incident rod recoil device for SHPB test |
| CN109323937A (en) * | 2018-11-23 | 2019-02-12 | 浙江大学 | A kind of Hopkinson pressure bar damping unit |
| CN109323937B (en) * | 2018-11-23 | 2023-10-31 | 浙江大学 | Hopkinson pressure bar damping device |
| CN114026404A (en) * | 2019-03-28 | 2022-02-08 | 伊利诺斯工具制品有限公司 | Collision mitigation device and material testing system with collision mitigation device |
| CN111071733B (en) * | 2019-12-31 | 2024-05-10 | 中冶北方（大连）工程技术有限公司 | Pneumatic device and method for detecting operation and breakage of adhesive tape |
| CN111071735A (en) * | 2019-12-31 | 2020-04-28 | 中冶北方（大连）工程技术有限公司 | Power frequency transmission adhesive tape running and slipping detection device and detection method |
| CN111071733A (en) * | 2019-12-31 | 2020-04-28 | 中冶北方（大连）工程技术有限公司 | Pneumatic device and method for detecting running and breakage of adhesive tape |
| CN111071735B (en) * | 2019-12-31 | 2024-05-10 | 中冶北方（大连）工程技术有限公司 | Device and method for detecting operation and slipping of power frequency transmission adhesive tape |
| CN111562178A (en) * | 2020-06-28 | 2020-08-21 | 天津大学 | Dynamic tensile test device with kinetic energy absorption and test method |
| CN113607545A (en) * | 2021-08-17 | 2021-11-05 | 西北工业大学 | Single pulse separation type Hopkinson pull rod experiment device based on electromagnetic force loading |
| CN113607545B (en) * | 2021-08-17 | 2024-05-07 | 西北工业大学 | Single pulse separation type Hopkinson pull rod experimental device based on electromagnetic force loading |
| CN117470639B (en) * | 2023-12-22 | 2024-04-09 | 深圳大学 | Energy absorption buffer device and method applied to dynamic true triaxial electromagnetic Hopkinson bar |
| CN117470639A (en) * | 2023-12-22 | 2024-01-30 | 深圳大学 | Energy absorption buffer device and method applied to dynamic true triaxial electromagnetic Hopkinson bar |
| CN118168962A (en) * | 2024-05-14 | 2024-06-11 | 四川大学 | Single-pulse experimental device and experimental method based on Hopkinson pressure bar |
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Application publication date: 20160727 |
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