CN111413231A - Small-stroke electromagnetic resonance type axial tension-compression fatigue test method - Google Patents
Small-stroke electromagnetic resonance type axial tension-compression fatigue test method Download PDFInfo
- Publication number
- CN111413231A CN111413231A CN202010255082.XA CN202010255082A CN111413231A CN 111413231 A CN111413231 A CN 111413231A CN 202010255082 A CN202010255082 A CN 202010255082A CN 111413231 A CN111413231 A CN 111413231A
- Authority
- CN
- China
- Prior art keywords
- winding
- pole
- tension
- winding group
- outer end
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- 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
- G01N3/32—Investigating strength properties of solid materials by application of mechanical stress by applying repeated or pulsating forces
- G01N3/38—Investigating strength properties of solid materials by application of mechanical stress by applying repeated or pulsating forces generated by electromagnetic means
-
- 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
- G01N3/02—Details
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0001—Type of application of the stress
- G01N2203/0005—Repeated or cyclic
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0016—Tensile or compressive
- G01N2203/0017—Tensile
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0016—Tensile or compressive
- G01N2203/0019—Compressive
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/003—Generation of the force
- G01N2203/005—Electromagnetic means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0058—Kind of property studied
- G01N2203/0069—Fatigue, creep, strain-stress relations or elastic constants
- G01N2203/0073—Fatigue
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/025—Geometry of the test
- G01N2203/0252—Monoaxial, i.e. the forces being applied along a single axis of the specimen
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Electromagnetism (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a small-stroke electromagnetic resonance type axial tension-compression fatigue test method. The existing fatigue test has the disadvantages of unadjustable working frequency, low control precision and slow response speed. The first chuck and the first tension and compression bar, and the second chuck and the second tension and compression bar are fixed; two ends of the test piece are respectively clamped by a first chuck and a second chuck; the frequency modulation instrument generates harmonic current, so that the positive winding set and the negative winding set respectively generate magnetic fields and electromagnetic forces with different polarities to drive the first tension and compression rod and the second tension and compression rod, and further realize tension and compression fatigue tests, tension fatigue tests or pressure fatigue tests. The electromagnetic driving circuit has the advantages of high electromagnetic driving control precision, high response speed, low noise and adjustable frequency and waveform of working current.
Description
Technical Field
The invention belongs to the technical field of fatigue tests, and particularly relates to a small-stroke electromagnetic resonance type axial tension-compression fatigue test method.
Background
The fatigue test has very important significance in the process of material research, development and application. At present, the most widely applied test mainly comprises an electro-hydraulic servo fatigue test and an electromagnetic resonance type high-frequency fatigue test, wherein the electro-hydraulic servo type fatigue test has the characteristics of outputting large thrust, large displacement, low frequency and the like, but has the defects of complex structure, high production cost and poor amplitude controllability; in contrast, the electromagnetic resonance type high-frequency fatigue test has high working frequency, short test time and low energy consumption, but has high noise, low control precision and slow response speed. Therefore, the market needs a fatigue test method which has adjustable working frequency, high control precision and high response speed and can be used for small-stroke tests.
Disclosure of Invention
The invention aims to provide a small-stroke electromagnetic resonance type axial tension-compression fatigue test method aiming at the conditions that the existing fatigue test has the defects of unadjustable working frequency, low control precision, low response speed, large noise, complex structure and high production cost and can not meet the requirements of small-displacement fatigue tests, the method is applicable to the small-stroke fatigue tests, has the advantages of adjustable working frequency, high control precision, high response speed, low noise, energy conservation, environmental protection, compact structure and low cost, and meets the requirements of the existing economic development. The fatigue test method can not only carry out the resonance type tension-compression fatigue test, but also respectively carry out the tension fatigue test and the pressure fatigue test.
The invention is realized by adopting the following technical scheme:
the invention specifically comprises the following steps:
step one, arranging a frequency modulation instrument on a base; two winding coils which are different in winding direction and are connected in series are wound at two ends of one winding drum to form a positive winding group; two winding coils which are different in winding direction and are connected in series are arranged at two ends of the other winding drum to form a reverse winding group, the winding directions of the two winding coils at the opposite ends of the forward winding group and the reverse winding group are different, and the winding directions of the two winding coils at the back ends of the two winding coils are also different; the two winding coils at the opposite ends of the positive winding group and the reverse winding group are respectively and electrically connected with the two ends of a starting switch on the frequency modulation instrument, the winding coil at the outer end of the positive winding group is electrically connected with the positive electrode of an output power supply of the frequency modulation instrument, the winding coil at the outer end of the reverse winding group is electrically connected with the negative electrode of the output power supply of the frequency modulation instrument, so that the voltage of the connection end of the positive winding group and the output power supply of the frequency modulation instrument is positive, and the magnetic pole at the outer end of the winding coil;
step two, one end of the winding drum of the positive winding group is supported on a first bearing seat through a bearing, and the axial positioning of the winding drum and the first bearing seat is realized through a clamp spring; fixing a first bearing seat on a first base; one end of the winding drum of the reverse winding group is supported on a sixth bearing seat through a bearing, and the winding drum and the sixth bearing seat are axially positioned through a clamp spring; fixing a sixth bearing seat on the fourth base; the first base and the fourth base are fixed on the base; fixing a first permanent magnet box at the position where the winding coil is not wound on the winding coil of the forward winding group, and fixing a second permanent magnet box at the position where the winding coil is not wound on the winding coil of the reverse winding group; the permanent magnet S pole arranged in the first permanent magnet box is fixed with one end of the first tension and compression rod, and the permanent magnet S pole arranged in the second permanent magnet box is fixed with one end of the second tension and compression rod; the first tension and compression rod is supported on a second bearing seat and a third bearing seat through bearings, and the second tension and compression rod is supported on a fourth bearing seat and a fifth bearing seat through bearings; the second bearing seat and the third bearing seat are fixed on the second base, and the fourth bearing seat and the fifth bearing seat are fixed on the third base; the second base and the third base are both fixed on the base.
Fixing the first chuck and the other end of the first tension and compression rod, and fixing the second chuck and the other end of the second tension and compression rod; two ends of the test piece are respectively clamped by the first chuck and the second chuck.
And step four, starting the frequency modulation instrument through the starting switch, wherein the frequency modulation instrument generates harmonic current, so that the positive winding set and the negative winding set respectively generate magnetic fields and electromagnetic forces with different polarities, and the resonant fatigue test is realized.
Further, the resonance type fatigue test is divided into a tension and compression fatigue test, a tension fatigue test and a pressure fatigue test according to different harmonic currents generated by the frequency modulation instrument;
the tensile and compressive fatigue test is as follows: when the harmonic current generated by the frequency modulation instrument is changed in a positive and negative alternate period, in a time period when the harmonic current is a positive value, the outer end magnetic pole of the outer end winding coil of the positive winding group is N pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is S pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is S pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is N pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is N pole, the outer end magnetic pole of the inner end winding coil of the reverse winding group is S pole, the inner end magnetic pole of the outer end winding coil of the reverse winding group is S pole, and the outer end magnetic. Because the outer end magnetic poles of the permanent magnets in the first permanent magnet box and the second permanent magnet box are N poles, the first permanent magnet box and the second permanent magnet box are respectively positioned at the positions where the coil is not wound between the positive winding group and the reverse winding group, the like magnetic poles repel each other, and the opposite magnetic poles attract each other, the outer end of the permanent magnet in the first permanent magnet box is attracted by attraction force, the inner end of the permanent magnet in the second permanent magnet box is attracted by repulsion force, and the outer end of the permanent magnet in the second permanent magnet box is attracted by attraction force, so that the first tension rod and the second tension rod are driven to simultaneously; in the time period when the harmonic current is negative, the outer end magnetic pole of the outer end winding coil of the positive winding group is S pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is N pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is N pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is S pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is S pole, the outer end magnetic pole of the inner end winding coil of the reverse winding group is N pole, the inner end magnetic pole of the outer end winding coil of the reverse winding group is N pole, and the outer end magnetic pole of the outer end winding coil of; therefore, the first and second tension and compression rods simultaneously generate pressure towards the inner side. And the tension-compression fatigue tests with different working frequencies are realized by controlling the period length of the harmonic current.
The tensile fatigue test is as follows: when the harmonic current generated by the frequency modulation instrument is changed in a periodic positive pulse mode, in a time period when the harmonic current is a positive value, the outer end magnetic pole of the coil at the outer end of the positive winding group is N pole, the inner end magnetic pole of the coil at the outer end of the positive winding group is S pole, the outer end magnetic pole of the coil at the inner end of the positive winding group is S pole, the inner end magnetic pole of the coil at the inner end of the positive winding group is N pole, the inner end magnetic pole of the coil at the inner end of the reverse winding group is N pole, the outer end magnetic pole of the coil at the inner end of the reverse winding group is S pole, the inner end magnetic pole of the coil at the outer end of the reverse winding group is S pole; therefore, the first and second tension and compression rods simultaneously generate outward tension. In the time period of not passing harmonic current, the forward winding group and the reverse winding group do not generate magnetic field force, and the first tension and compression bar and the second tension and compression bar are not stressed. By controlling the period length of the harmonic current, the tensile fatigue tests with different working frequencies are realized.
The pressure fatigue test was as follows: when the harmonic current generated by the frequency modulation instrument is changed in a periodic negative pulse mode, the positive winding group and the reverse winding group do not generate magnetic field force in a current-off time period, and the first tension and compression rod and the second tension and compression rod are not stressed; in the time period when the harmonic current is negative, the outer end magnetic pole of the outer end winding coil of the positive winding group is S pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is N pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is N pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is S pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is S pole, the outer end magnetic pole of the inner end winding coil of the reverse winding group is N pole, the inner end magnetic pole of the outer end winding coil of the reverse winding group is N pole, and the outer end magnetic pole of the outer end winding coil of; therefore, the first and second tension and compression rods simultaneously generate inward pressure; by controlling the period length of the harmonic current, the pressure fatigue tests with different working frequencies are realized.
Furthermore, supporting legs are arranged at the bottom of the base.
Furthermore, the calibers of the two chucks are adjustable.
Further, in the resonant fatigue test process, if an emergency exists, the frequency modulation instrument is stopped by the emergency stop button.
Further, the waveform of the harmonic current is sinusoidal.
The invention has the following beneficial effects:
1. the harmonic current processed by the frequency converter enables the polarities of the magnetic poles at the two ends of the forward winding group and the reverse winding group to be continuously changed, so that a magnetic field force with a period change is generated, and the forward winding group and the reverse winding group are attracted or repelled with the permanent magnet box due to the interaction of the magnetic field force and the permanent magnet, so that the tension and compression rod is driven to generate a tension and compression force with a period change, and a resonant tension and compression fatigue test on a test piece is realized.
2. The harmonic current frequency generated by the control can generate alternating magnetic fields with different frequencies so as to realize resonance type tension and compression fatigue tests under different working frequencies, the waveform of the harmonic current is controlled so as to generate alternating magnetic fields and magnetic field forces in a single direction (forward or reverse) so as to realize tension or pressure fatigue tests, the electromagnetic drive is controllable, and the working frequency is adjustable.
3. The electromagnetic drive has high control precision, fast response speed, low noise and adjustable frequency and waveform of the working current. Compared with the existing fatigue test method, the invention can be suitable for the fatigue test with small stroke, and the machine is horizontal, thereby not only eliminating the influence of gravity on the test, but also having convenient operation, compact structure and low cost.
Drawings
FIG. 1 is a front view of the present invention implementing a test piece stretching process;
FIG. 2 is a front view of the compression process of the test piece according to the present invention;
FIGS. 3(a) and 3(b) are schematic diagrams of directions of harmonic current and electromagnetic force, respectively, when the tensile-compressive fatigue test is performed according to the present invention;
FIGS. 4(a) and 4(b) are schematic diagrams of harmonic current and electromagnetic force, respectively, when the tensile fatigue test of the present invention is performed;
FIGS. 5(a) and 5(b) are schematic diagrams of harmonic current and electromagnetic force, respectively, when the present invention is subjected to a pressure fatigue test;
fig. 6 is a top view of the device of the present invention.
In the figure: 1. supporting legs, 2, a base, 3, a first base, 4, a first bearing seat, 5, a positive winding group, 6, a first permanent magnet box, 7, a second bearing seat, 8, a third bearing seat, 9, a second base seat, 10, a first tension and compression rod, 11, a first chuck, 12, a test piece, 13, a second chuck, 14, a fourth bearing seat, 15, a second tension and compression rod, 16, a fifth bearing seat, 17, a third base seat, 18, a second permanent magnet box, 19, a reverse winding group, 20, a sixth bearing seat, 21, a fourth base seat, 22, a frequency modulation instrument, 22-1, a starting switch, 22-2 and an emergency stop button.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
As shown in fig. 1, 2 and 6, the method for the small-stroke electromagnetic resonance type axial tension-compression fatigue test specifically comprises the following steps:
step one, arranging a frequency modulation instrument 22 on a base 2; the bottom of the base 2 is provided with supporting legs 1; two winding coils which are different in winding direction and are connected in series are wound at two ends of one winding drum to form a positive winding group 5; two winding coils which are different in winding direction and are connected in series are arranged at two ends of the other winding cylinder to form a reverse winding group 19, the winding directions of the two winding coils at the opposite ends of the forward winding group and the reverse winding group are different, and the winding directions of the two winding coils at the back ends of the two winding coils are also different; electrically connecting two winding coils at opposite ends of the forward winding group and the reverse winding group with two ends of a starting switch on the frequency modulation instrument 22 respectively, electrically connecting the winding coil at the outer end of the forward winding group with the positive electrode of an output power supply of the frequency modulation instrument 22, and electrically connecting the winding coil at the outer end of the reverse winding group with the negative electrode of the output power supply of the frequency modulation instrument 22; the voltage of the output power supply connecting end of the positive winding group and the frequency modulation instrument 22 is positive, and the outer end magnet of the outer end winding coil of the positive winding group is an N pole;
step two, one end of the winding reel of the positive winding group 5 is supported on the first bearing seat 4 through a bearing, and is axially positioned with the first bearing seat 4 through a clamp spring; fixing the first bearing block 4 on the first base 3; one end of the winding drum of the reverse winding group is supported on the sixth bearing seat 20 through a bearing, and is axially positioned with the sixth bearing seat 20 through a snap spring; fixing the sixth bearing housing 20 to the fourth base 21; the first base 3 and the fourth base 21 are both fixed on the base 2; fixing the first permanent magnet box 6 at the position where the winding coil is not wound on the winding coil of the forward winding group, and fixing the second permanent magnet box 18 at the position where the winding coil is not wound on the winding coil of the reverse winding group; the permanent magnet S pole arranged in the first permanent magnet box 6 is fixed with one end of the first tension and compression bar 10, and the permanent magnet S pole arranged in the second permanent magnet box 18 is fixed with one end of the second tension and compression bar 15; the first tension and compression rod 10 is supported on the second bearing seat 7 and the third bearing seat 8 through bearings, and the second tension and compression rod 15 is supported on the fourth bearing seat 14 and the fifth bearing seat 16 through bearings; the first and second tension and compression bars 10, 15 are axially movable. The second bearing seat 7 and the third bearing seat 8 are both fixed on the second base 9, and the fourth bearing seat 14 and the fifth bearing seat 16 are both fixed on the third base 17; the second base 9 and the third base 17 are both fixed on the base 2; magnetic field forces generated at the two ends of the forward winding group and the reverse winding group attract or repel each other so as to drive the first tension and compression rod and the second tension and compression rod to generate tension or pressure.
Fixing the first chuck 11 and the other end of the first tension and compression rod 10, and fixing the second chuck 13 and the other end of the second tension and compression rod 15; both ends of the test piece 12 are clamped by a first chuck 11 and a second chuck 13, respectively. The calibers of the two chucks can be manually adjusted to accommodate test pieces 12 of different diameters.
Fourthly, starting the frequency modulation instrument 22 through the starting switch 22-1, wherein the frequency modulation instrument generates harmonic current, so that the positive winding set and the negative winding set respectively generate magnetic fields and electromagnetic forces with different polarities, and the resonant fatigue test is realized; in the resonant fatigue test process, if an emergency exists, the frequency modulation instrument 22 is stopped to work through the emergency stop button 22-2. According to different harmonic currents generated by a frequency modulation instrument, the resonant fatigue test is divided into a tension-compression fatigue test, a tension fatigue test and a pressure fatigue test;
as shown in fig. 1, 2 and 3(a), the tensile and compressive fatigue test is as follows: when the harmonic current generated by the frequency modulation instrument changes in sine type positive and negative alternate cycles, the harmonic current is at 0-t1Harmonic current I is positive in the time period, so that the outer end magnetic pole of the outer end winding coil of the positive winding group is N pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is S pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is S pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is N pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is N pole, the outer end magnetic pole of the inner end winding coil of the reverse winding group is S pole, the inner end magnetic pole of the outer end winding coil of the reverse winding group is S pole, and the outer end magnetic pole of the outer end winding coil. And because the magnetic poles at the outer ends of the permanent magnets in the first permanent magnet box 6 and the second permanent magnet box 18 are both N poles, the magnetic poles at the outer ends of the permanent magnets are all N poles, andthe first permanent magnet box and the second permanent magnet box are respectively positioned at the positions where the winding coils are not wound between the positive winding group and the negative winding group, like magnetic poles repel each other, and opposite magnetic poles attract each other, so that the outer end of the permanent magnet in the first permanent magnet box 6 is attracted by attraction force, the inner end of the permanent magnet is attracted by repulsion force, the inner end of the permanent magnet in the second permanent magnet box 18 is attracted by repulsion force, and the outer end of the permanent magnet is attracted by attraction force, so that the first tension rod and the second tension rod are driven to simultaneously generate outward tension force F, as shown; at t1-t2The harmonic current in the time period is a negative value, so that the outer end magnetic pole of the outer end winding coil of the positive winding group is an S pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is an N pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is an N pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is an S pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is an S pole, the outer end magnetic pole of the inner end winding coil of the reverse winding group is an N pole, the inner end magnetic pole of the outer end winding coil of the reverse winding group is an N pole, and the; therefore, the first and second tension/compression rods simultaneously generate inward pressure, as shown in fig. 2. 0-t2The time period is one cycle, a tension and compression test process is realized in one cycle, fig. 3(b) is a schematic diagram showing changes of the stress directions of the first and second tension and compression rods along with harmonic current, and it is specified that the outward tension of the first and second tension and compression rods is positive and the inward pressure is negative. And the tension-compression fatigue tests with different working frequencies are realized by controlling the period length of the harmonic current. At t2-t3The change rule of harmonic current in the time period is 0-t1The change rule in the time period is consistent, at t3-t4The change rule of harmonic current in time period and at t1-t2The change rule in the time period is consistent.
As shown in fig. 1 and 4(a), the tensile fatigue test is as follows: when the harmonic current generated by the frequency modulation instrument 22 is in periodic sine positive pulse change at 0-t1The harmonic current in the time period is positive, so that the outer end magnetic pole of the outer end winding coil of the positive winding group is N pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is S pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is S pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is N pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is N pole, and the reverse winding group is N poleThe outer end magnetic pole of the coil at the inner end of the wire group is an S pole, the inner end magnetic pole of the coil at the outer end of the reverse winding group is an S pole, and the outer end magnetic pole of the coil at the outer end of the reverse winding group is an N pole; therefore, the first and second tension/compression bars simultaneously generate outward tension, as shown in fig. 1. At t1-t2The current is not conducted in the time period, the forward winding group and the reverse winding group do not generate magnetic field force, and the first tension and compression rod and the second tension and compression rod are not stressed. The variation of the stress of the first and second tension-compression rods with the harmonic current is shown in FIG. 4(b) at 0-t2The first tension and compression rod and the second tension and compression rod only generate discontinuous tension in one period of the time period, and the tension fatigue tests with different working frequencies are realized by controlling the period length of harmonic current.
As shown in fig. 2 and 5(a), the pressure fatigue test is as follows: when the harmonic current generated by the frequency modulation instrument is in periodic sine negative pulse change, the harmonic current is at 0-t1No current is conducted in a time period, the forward winding group and the reverse winding group do not generate magnetic field force, and the first tension and compression bar and the second tension and compression bar are not stressed; at t1-t2The harmonic current in the time period is a negative value, so that the outer end magnetic pole of the outer end winding coil of the positive winding group is an S pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is an N pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is an N pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is an S pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is an S pole, the outer end magnetic pole of the inner end winding coil of the reverse winding group is an N pole, the inner end magnetic pole of the outer end winding coil of the reverse winding group is an N pole, and the; therefore, the first and second tension/compression rods simultaneously generate inward pressure, as shown in fig. 2. The variation of the stress of the first and second tension-compression rods with the harmonic current is shown in FIG. 5(b) at 0-t2The first tension and compression rod and the second tension and compression rod only generate discontinuous pressure in one period of the time period, and the pressure fatigue tests with different working frequencies are realized by controlling the period length of harmonic current.
Claims (6)
1. The small-stroke electromagnetic resonance type axial tension-compression fatigue test method is characterized by comprising the following steps of: the method comprises the following specific steps:
step one, arranging a frequency modulation instrument on a base; two winding coils which are different in winding direction and are connected in series are wound at two ends of one winding drum to form a positive winding group; two winding coils which are different in winding direction and are connected in series are arranged at two ends of the other winding drum to form a reverse winding group, the winding directions of the two winding coils at the opposite ends of the forward winding group and the reverse winding group are different, and the winding directions of the two winding coils at the back ends of the two winding coils are also different; the two winding coils at the opposite ends of the positive winding group and the reverse winding group are respectively and electrically connected with the two ends of a starting switch on the frequency modulation instrument, the winding coil at the outer end of the positive winding group is electrically connected with the positive electrode of an output power supply of the frequency modulation instrument, the winding coil at the outer end of the reverse winding group is electrically connected with the negative electrode of the output power supply of the frequency modulation instrument, so that the voltage of the connection end of the positive winding group and the output power supply of the frequency modulation instrument is positive, and the magnetic pole at the outer end of the winding coil;
step two, one end of the winding drum of the positive winding group is supported on a first bearing seat through a bearing, and the axial positioning of the winding drum and the first bearing seat is realized through a clamp spring; fixing a first bearing seat on a first base; one end of the winding drum of the reverse winding group is supported on a sixth bearing seat through a bearing, and the winding drum and the sixth bearing seat are axially positioned through a clamp spring; fixing a sixth bearing seat on the fourth base; the first base and the fourth base are fixed on the base; fixing a first permanent magnet box at the position where the winding coil is not wound on the winding coil of the forward winding group, and fixing a second permanent magnet box at the position where the winding coil is not wound on the winding coil of the reverse winding group; the permanent magnet S pole arranged in the first permanent magnet box is fixed with one end of the first tension and compression rod, and the permanent magnet S pole arranged in the second permanent magnet box is fixed with one end of the second tension and compression rod; the first tension and compression rod is supported on a second bearing seat and a third bearing seat through bearings, and the second tension and compression rod is supported on a fourth bearing seat and a fifth bearing seat through bearings; the second bearing seat and the third bearing seat are fixed on the second base, and the fourth bearing seat and the fifth bearing seat are fixed on the third base; the second base and the third base are both fixed on the base;
fixing the first chuck and the other end of the first tension and compression rod, and fixing the second chuck and the other end of the second tension and compression rod; two ends of the test piece are respectively clamped by a first chuck and a second chuck;
and step four, starting the frequency modulation instrument through the starting switch, wherein the frequency modulation instrument generates harmonic current, so that the positive winding set and the negative winding set respectively generate magnetic fields and electromagnetic forces with different polarities, and the resonant fatigue test is realized.
2. The small-stroke electromagnetic resonance type axial tension-compression fatigue test method according to claim 1, characterized in that: according to different harmonic currents generated by a frequency modulation instrument, the resonant fatigue test is divided into a tension-compression fatigue test, a tension fatigue test and a pressure fatigue test;
the tensile and compressive fatigue test is as follows: when the harmonic current generated by the frequency modulation instrument is changed in a positive and negative alternate cycle manner, in a time period when the harmonic current is a positive value, the outer end magnetic pole of the outer end winding coil of the positive winding group is an N pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is an S pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is an S pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is an N pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is an N pole, the outer end magnetic pole of the inner end winding coil of the reverse winding group is an S pole, the inner end magnetic pole of the outer end winding coil of the reverse winding group is an; because the outer end magnetic poles of the permanent magnets in the first permanent magnet box and the second permanent magnet box are N poles, the first permanent magnet box and the second permanent magnet box are respectively positioned at the positions where the coil is not wound between the positive winding group and the reverse winding group, the like magnetic poles repel each other, and the opposite magnetic poles attract each other, the outer end of the permanent magnet in the first permanent magnet box is attracted by attraction force, the inner end of the permanent magnet in the second permanent magnet box is attracted by repulsion force, and the outer end of the permanent magnet in the second permanent magnet box is attracted by attraction force, so that the first tension rod and the second tension rod are driven to simultaneously; in the time period when the harmonic current is negative, the outer end magnetic pole of the outer end winding coil of the positive winding group is S pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is N pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is N pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is S pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is S pole, the outer end magnetic pole of the inner end winding coil of the reverse winding group is N pole, the inner end magnetic pole of the outer end winding coil of the reverse winding group is N pole, and the outer end magnetic pole of the outer end winding coil of; therefore, the first and the second tension and compression rods simultaneously generate pressure towards the inner side; by controlling the period length of the harmonic current, the tension-compression fatigue tests with different working frequencies are realized;
the tensile fatigue test is as follows: when the harmonic current generated by the frequency modulation instrument is changed in a periodic positive pulse mode, in a time period when the harmonic current is a positive value, the outer end magnetic pole of the coil at the outer end of the positive winding group is N pole, the inner end magnetic pole of the coil at the outer end of the positive winding group is S pole, the outer end magnetic pole of the coil at the inner end of the positive winding group is S pole, the inner end magnetic pole of the coil at the inner end of the positive winding group is N pole, the inner end magnetic pole of the coil at the inner end of the reverse winding group is N pole, the outer end magnetic pole of the coil at the inner end of the reverse winding group is S pole, the inner end magnetic pole of the coil at the outer end of the reverse winding group is S pole; therefore, the first and second tension and compression rods simultaneously generate outward tension; in the time period of no harmonic current, the forward winding group and the reverse winding group do not generate magnetic field force, and the first tension and compression bar and the second tension and compression bar are not stressed; the tensile fatigue tests with different working frequencies are realized by controlling the period length of the harmonic current;
the pressure fatigue test was as follows: when the harmonic current generated by the frequency modulation instrument is changed in a periodic negative pulse mode, the positive winding group and the reverse winding group do not generate magnetic field force in a current-off time period, and the first tension and compression rod and the second tension and compression rod are not stressed; in the time period when the harmonic current is negative, the outer end magnetic pole of the outer end winding coil of the positive winding group is S pole, the inner end magnetic pole of the outer end winding coil of the positive winding group is N pole, the outer end magnetic pole of the inner end winding coil of the positive winding group is N pole, the inner end magnetic pole of the inner end winding coil of the positive winding group is S pole, the inner end magnetic pole of the inner end winding coil of the reverse winding group is S pole, the outer end magnetic pole of the inner end winding coil of the reverse winding group is N pole, the inner end magnetic pole of the outer end winding coil of the reverse winding group is N pole, and the outer end magnetic pole of the outer end winding coil of; therefore, the first and second tension and compression rods simultaneously generate inward pressure; by controlling the period length of the harmonic current, the pressure fatigue tests with different working frequencies are realized.
3. The small-stroke electromagnetic resonance type axial tension-compression fatigue test method according to claim 1 or 2, characterized in that: the bottom of the base is provided with supporting legs.
4. The small-stroke electromagnetic resonance type axial tension-compression fatigue test method according to claim 1 or 2, characterized in that: the calibers of the two chucks are adjustable.
5. The small-stroke electromagnetic resonance type axial tension-compression fatigue test method according to claim 1 or 2, characterized in that: and in the process of the resonant fatigue test, if an emergency exists, the frequency modulation instrument is stopped by the emergency stop button.
6. The small-stroke electromagnetic resonance type axial tension-compression fatigue test method according to claim 1 or 2, characterized in that: the waveform of the harmonic current is sinusoidal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010255082.XA CN111413231B (en) | 2020-04-02 | 2020-04-02 | Small-stroke electromagnetic resonance type axial tension-compression fatigue test method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010255082.XA CN111413231B (en) | 2020-04-02 | 2020-04-02 | Small-stroke electromagnetic resonance type axial tension-compression fatigue test method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111413231A true CN111413231A (en) | 2020-07-14 |
| CN111413231B CN111413231B (en) | 2022-11-08 |
Family
ID=71491754
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010255082.XA Active CN111413231B (en) | 2020-04-02 | 2020-04-02 | Small-stroke electromagnetic resonance type axial tension-compression fatigue test method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111413231B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112286141A (en) * | 2020-10-28 | 2021-01-29 | 山东钢铁集团日照有限公司 | Closed-loop servo control electromagnet buckling-instability-preventing device |
| CN114910355A (en) * | 2022-05-15 | 2022-08-16 | 西北工业大学 | Device capable of directly generating tensile stress wave |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1216707A1 (en) * | 1983-10-20 | 1986-03-07 | Институт Механики Ан Усср | Arrangement for specimen tension-compression fatigue testing |
| CN102331370A (en) * | 2011-10-11 | 2012-01-25 | 吉林大学 | In-situ high-frequency fatigue material mechanical test platform under scanning electron microscope based on stretching/compressing mode |
| CN107144474A (en) * | 2017-04-11 | 2017-09-08 | 中国航发北京航空材料研究院 | A kind of high temperature super high cycle fatigue pilot system and test method |
| CN108627333A (en) * | 2018-07-19 | 2018-10-09 | 中国人民解放军陆军装甲兵学院 | Fatigue test electromagnetic exciting loading device |
| CN112880992A (en) * | 2021-01-15 | 2021-06-01 | 一汽解放汽车有限公司 | System and method for crankshaft bending and twisting fatigue test |
-
2020
- 2020-04-02 CN CN202010255082.XA patent/CN111413231B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1216707A1 (en) * | 1983-10-20 | 1986-03-07 | Институт Механики Ан Усср | Arrangement for specimen tension-compression fatigue testing |
| CN102331370A (en) * | 2011-10-11 | 2012-01-25 | 吉林大学 | In-situ high-frequency fatigue material mechanical test platform under scanning electron microscope based on stretching/compressing mode |
| CN107144474A (en) * | 2017-04-11 | 2017-09-08 | 中国航发北京航空材料研究院 | A kind of high temperature super high cycle fatigue pilot system and test method |
| CN108627333A (en) * | 2018-07-19 | 2018-10-09 | 中国人民解放军陆军装甲兵学院 | Fatigue test electromagnetic exciting loading device |
| CN112880992A (en) * | 2021-01-15 | 2021-06-01 | 一汽解放汽车有限公司 | System and method for crankshaft bending and twisting fatigue test |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112286141A (en) * | 2020-10-28 | 2021-01-29 | 山东钢铁集团日照有限公司 | Closed-loop servo control electromagnet buckling-instability-preventing device |
| CN114910355A (en) * | 2022-05-15 | 2022-08-16 | 西北工业大学 | Device capable of directly generating tensile stress wave |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111413231B (en) | 2022-11-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111413231B (en) | Small-stroke electromagnetic resonance type axial tension-compression fatigue test method | |
| CN202167973U (en) | Short-stroke reciprocating linear motor | |
| CN101552081B (en) | Permanent magnetic operating mechanism making straight reciprocating motion | |
| US5886442A (en) | Magnetic attraction driving engine using permanent magnet | |
| CN201038194Y (en) | Magnetostrictive device and linear motor and vibration device adopting same | |
| CN212301174U (en) | Small-stroke electromagnetic resonance type axial tension-compression fatigue testing machine | |
| CN115765376A (en) | Linear motor and driving and controlling method thereof | |
| CN205725399U (en) | Permanent magnetic Reciprocative straight line motor | |
| CN111049348B (en) | Non-permanent-magnet electromagnetic force driven reciprocating power device | |
| JP2015512608A5 (en) | ||
| KR101025387B1 (en) | Electric motor using rotary plate having fixed plate with divided coil body and divided magnetic body | |
| KR20090055570A (en) | Magnetically driven reciprocating system and method | |
| CN221779622U (en) | Electromagnetic force driven air compression structure and oxygenerator | |
| Huang et al. | Research on voice coil motor for a new construction with wireless power supply | |
| CN110905491A (en) | Automatic braking accurate control type mud pulser for petroleum drilling | |
| Chen et al. | Energy consumption analysis of a linear motor | |
| CN113890299B (en) | Engine system for generating power based on electrified coil and permanent magnet | |
| CN2332061Y (en) | Micro-consume energy-saving absorption-release device | |
| CN104009568A (en) | Small-stroke voice coil linear motor | |
| CN2171170Y (en) | Double permanent-magnet straight-line reciprocating electric motor | |
| CN210443365U (en) | Push type electromagnet for driving | |
| CN213637443U (en) | Galfenol alloy driven double-inertia impact type precise stepping micro linear motor | |
| Guo et al. | Magnetic field and performance analysis of novel double-side tubular permanent magnet machines | |
| CN201038975Y (en) | Permanent magnetic engine | |
| CN2657275Y (en) | Permanent-magnetic linear vibration electric machine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |