CN103234725A - Method for testing vibration damage limit of anti-skidding braking control box - Google Patents
Method for testing vibration damage limit of anti-skidding braking control box Download PDFInfo
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- CN103234725A CN103234725A CN2013101698957A CN201310169895A CN103234725A CN 103234725 A CN103234725 A CN 103234725A CN 2013101698957 A CN2013101698957 A CN 2013101698957A CN 201310169895 A CN201310169895 A CN 201310169895A CN 103234725 A CN103234725 A CN 103234725A
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Abstract
The invention discloses a method for testing the vibration damage limit of an anti-skidding braking control box. The method comprises the following steps of applying anti-skidding braking working current while applying vibration stepping stress; testing whether the performance of the anti-skidding braking control box is qualified or not; if the performance of the anti-skidding braking control box is unqualified, giving an improvement suggest of improving the vibration resistance of the control box; and if the performance of the anti-skidding braking control box is qualified, continuing testing till a required vibration damage limit is reached. Testing of the vibration damage limit of the control box by adopting vibration stepping test belongs to one of the contents of long acceleration service life test, and is used for making a high acceleration stress sieving test section. According to the method, the vibration damage limit of the anti-skidding braking control box is tested by adopting an electric vibration table, working current is applied in a testing process, the improvement suggest is provided and technical improvement is made according to tested vibration failure hidden danger, and vibration damage limit test data determined after improvement is used for making the high acceleration stress sieving test section.
Description
Technical field
The present invention relates to the electronic product field of airplane in transportation category brake system, specifically is a kind of method of testing that adopts sine sweep and broadband to carry out antiskid brake control enclosure vibration fault at random.
Background technology
The vibration step stress test is one of content of GMW8287 " high accelerated aging, highly accelerated stress screen and sampling observation " standard, the present invention applies the vibration stepstress, carry out the cyclic process of technological improvement at vibration fault, proceed to unconditionally change again or when having reached desired value till.
The flutter failure limit is to break down in vibration Step test process, withdraws the vibration value that the performance of control enclosure can not be recovered behind the vibration stress.Can improve the flutter failure limit of antiskid brake control enclosure by technological improvement.
The vibration working limit is to break down in vibration Step test process, withdraws the vibration value that the performance of control enclosure can be recovered behind the vibration stress.Can improve the vibration working limit of antiskid brake control enclosure by technological improvement.
The antiskid brake control enclosure is the electronic product in the Aircraft Anti-skid Break Control; design has multiple function, any function such as to be protected not meet designing requirement to be and to break down between the wheel of left and right undercarriage wheel in antiskid function in take-off line brake function, the landing braking process, the ground protection function when landing, the landing mission.
According to general international standard GMW8287 explanation, when definite flutter failure stress limit, apply the vibration stepstress, do not apply working current; The present invention selects to apply the pulsating current of antiskid brake control enclosure antiskid brake function when applying the vibration stepstress, excite and environmental stress, fault that working current is relevant.
In order to improve the reliability of electronic product, adopt the Highly Accelerated Life Test technology to excite the potential faults of control enclosure in the world, the test figure that employing obtains in Highly Accelerated Life Test is formulated the highly accelerated stress screen test profile of control enclosure, quality inspection foundation as examination is dispatched from the factory substitutes the common screening technique in the original MIL-STD-2164 standard.Special-purpose section is adopted in highly accelerated stress screen test, and a kind of product is with the test profile of a special use, and the electronic product of special-purpose section by same model carries out Highly Accelerated Life Test and obtain.
The purpose of vibration Step test is the excitation electron product potential faults relevant with vibration, proposition is at the recommendation on improvement of vibration fault hidden danger and finish technological improvement, thereby improve vibration working limit and the breaking limit of control enclosure, shorten a kind of experimental technique of development time.The vibration parameters of highly accelerated stress screen derives from the vibration working limit data that vibration obtains in the Step test, and at the final state of the art of iterate improvement.This test not only can substitute the screening of conventional 80h with the highly accelerated stress screen of 3h~6h, and uses the experimental technique that proves a raising electronic product workmanship and production efficiency.
The electronic product of airlines such as external Boeing has just begun to promote vibration Step test technology in electronic product as far back as the sixties in last century.
According to the GMW8287 standard, the Step test of shaking of electronic product includes two parts content, and first iteration is carried out vibrotechnique and improved the vibration adaptation ability of raising control enclosure; It two is to determine the vibration parameters of highly accelerated stress screen test profile according to last technological improvement state.
The external GMW8287 of employing formulates the flutter failure marginal test that is subjected to trial product, but never leaks specific to the test method of the flutter failure limit that the is subjected to trial product top-secret technology as enterprise-level; Whether this standard is to applying the working stress not specified (NS) in vibration in the step stress test.
The reliability intensifying testing equipment is adopted in the vibration step stress test in the GMW8287 standard, and the reliability intensifying testing equipment has the mechanical vibrating system of Triaxiality and six degrees of freedom.
Present status in China:
Be subjected to the influence of external advanced experimental technique, domestic have tame individual proprietorship more than 100 or three money electronic enterprises approximately with the enterprise requirement of stepping vibration stress test as the electronic product development, be used for improving the flutter failure limit of electronic product, determine whether to carry out carrying out technological improvement at vibration fault hidden danger.But the product that dispatches from the factory is not carried out the highly accelerated stress screen test, and reason is the standard that domestic unmatchful electronic product is still implemented highly accelerated stress screen.
Beijing Institute of Aeronautics Research on Automobile's Reliability Engineering institute and Air China's industry 301 all existing more than 10 year history of vibration Step test technology of studying, but because external nearly 50 years technical know-how, make demestic user and product development unit lack understanding to this technology, government offices also do not issue the standard of this technology of application, so in untapped this technology in the development field of electronic product.
Because external long-term blockade on new techniques, present domestic electronic product still adopts common screening technique, and reason is the domestic standard of not putting into effect highly accelerated stress screen as yet, and enterprise does not carry out the foundation of highly accelerated stress screen test.One of purpose of vibration Step test is exactly the vibration stress value to be provided for the high shaker test section that accelerates.
The flutter failure marginal test of electronic product is both at home and abroad all carried out under off working state, the method that only applies the vibration stepstress and do not apply working current not exclusively conforms to the use state, because in use product is to bear environmental stress and working stress simultaneously, the data that adopt this classic method test to obtain owe true part.
In order to adapt to the national conditions that state-owned enterprise seldom introduces the reliability intensifying testing equipment of Triaxiality and six degrees of freedom vibrational system, the present invention adopts electric vibration table to vibrate Step test.
Existing vibration Step test method is compared with the technology of the present invention and is seen Table 1.
At application number be: the method that discloses a kind of definite aircraft antiskid brake control enclosure vibration working stress limit in 201110310884.7 the innovation and creation.This method has following technical characterictic:
A. adopt the reliability intensifying testing equipment, the steam hammer exciting has the characteristic of Triaxiality and six degrees of freedom, and the excitation method difference makes the testing program difference, shows installation direction and the vibration parameters aspect of antiskid brake control enclosure;
B. vibrational energy distribution is in the space of Triaxiality and six degrees of freedom, and is dispersed between 10Hz~10000Hz, and is better to the vibration fault hidden danger effect of component-level and plate level.
But the method for disclosed definite aircraft antiskid brake control enclosure vibration working stress limit also has following deficiency in 201110310884.7:
A. the mechanical vibrating system energy consumption of reliability intensifying testing equipment is bigger, compares with electric vibration table, excites identical fault need export about two times energy and just can reach and excite out of order purpose;
B. the reliability intensifying testing equipment can not carry out sine sweep, thereby can not determine the resonance frequency of control enclosure.
C. the vibration table of reliability intensifying testing equipment knocks the copper coin exciting by 9~24 pneumatic hammers, and amplitude is little;
D. the reliability intensifying testing equipment is owing to adopt pneumatic hammer to knock the copper coin exciting, and noise is big;
E. the reliability intensifying testing equipment is not so good as the electric vibrating system to the fault stimulation effect of complete machine level.
Because the advantage of electric vibration table can overcome the deficiency of reliability intensifying testing equipment, and the electric vibration table of state-owned enterprise is universal, therefore is necessary to study and adopts electric vibration table to carry out the technology of control enclosure vibration Step test.
Summary of the invention
For overcoming the scarce capacity that excites complete machine level vibration fault hidden danger in the prior art, the present invention proposes a kind of method of antiskid brake control enclosure flutter failure limit test.
Detailed process of the present invention may further comprise the steps:
Step 1 is determined vibration Step test parameter
Step-length, the retention time on each step-length, the antiskid brake working current of the vibration value when described test parameters comprises on-test, vibration Step test, apply mode and test exemplar quantity, and the vibration test required value of vibration value when reaching 18Grms.
Step 2 is formulated vibration Step test section
According to the step-length of vibration value during on-test of step 1 and the test determined, vibration Step test, on each step-length retention time, antiskid brake working current and apply mode, when the vibration value reaches 18Grms and later little vibration test required value, determine vibration Step test section.
In the described vibration Step test section, the vibration value during on-test that the vibration value is set to determine, the output current of test antiskid brake control enclosure, this antiskid brake control enclosure output current should be 0mA~20mA.According to the vibration step-length of determining the vibration value of shaking table is elevated to next test point, the output current of test antiskid brake control enclosure, this antiskid brake control enclosure output current should be 0mA~20mA.At the vibration retention time of each vibration level t
iThe vibration of=antiskid brake control enclosure stabilization time+test antiskid brake control enclosure required real time of output current, i=1~n.At the retention time of the little vibration level of each time t
j=test antiskid brake control enclosure required the real time of output current, j=1~m.
Repeat the vibration-test process of described rising vibration value-this value of maintenance, the vibration value that imposes on the antiskid brake control enclosure until shaking table reaches the determined flutter failure limit.
Step 3 is connected the antiskid brake control enclosure on the vibration table by vibration tong
The hole that the antiskid brake control enclosure is installed in vibration tong processing should be symmetrical between two parties, and install steel-wire screw-socket in the hole additional.
Carry out the sine sweep test according to HB5830.5 Fig. 3 E level, the frequency sweep frequency range is 10Hz~2000Hz, determines to take place the frequency of resonance, and this resonant frequency point should be avoided in installation site aboard.In vibration sweep check process, the excited vibration value that applies is 6Grms.
Step 5, the test vibration breaking limit
The antiskid brake control enclosure is fastened on the moving-coil of shaking table with vibration tong, connects vibration transducer, the closing test chamber door is with the control computing machine of Fig. 1 test profile inputted vibration platform.
The process of test vibration breaking limit is:
The initial value of shaking table is adjusted into 4Grms, the duration of vibration is 25min, the about 15min of performance test time that comprises the antiskid brake control enclosure, test the output current of antiskid brake control enclosure the first time, and the output current of described antiskid brake control enclosure is 0mA~20mA.
After first time end of test (EOT), according to the test profile of formulating, proceed to vibrate Step test with the step-length of 2Grms, vibrate value and be set to 6Grms, vibration duration is 25min, the about 15min of performance test time that comprises the antiskid brake control enclosure, test the output current of antiskid brake control enclosure the second time, and the output current of described antiskid brake control enclosure is 0mA~20mA.
After second time end of test (EOT), according to the test profile of formulating, proceed to vibrate Step test with the step-length of 2Grms, vibrate value and be set to 8Grms, vibration duration is 25min, the about 15min of performance test time that comprises the antiskid brake control enclosure tests the output current of antiskid brake control enclosure for the third time, and the output current of described antiskid brake control enclosure is 0mA~20mA.
Vibrate Step test according to above-mentioned test method, be increased to 18Grms until vibrating the step-length of value by 2Grms.
When the vibration value is increased to 18Grms, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, little time 15min that shakes.
Continuation rises to 20Grms with the vibration value of shaking table, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, little time 15min that shakes.
Continuation rises to 22Grms with the vibration value of shaking table, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, working current is 10mA after tested, does not reach the requirement that maximum output current is 20mA;
Antiskid brake control enclosure to the forfeiture brake function carries out technological improvement, makes it can export the antiskid brake working current of 0mA~20mA under the vibration condition of 22Grms, satisfies the antiskid brake functional requirement, makes it satisfy the follow-up test requirement.
When the vibration value of applying for the antiskid brake control enclosure when shaking table reaches 24Grms, if the antiskid brake working current of described antiskid brake control enclosure output does not satisfy the requirement of 0mA~20mA, then need this antiskid brake control enclosure is improved, make it satisfy the follow-up test requirement.
When shaking table gives vibration value that the antiskid brake control enclosure applies less than 24Grms, if the antiskid brake working current of described antiskid brake control enclosure output does not satisfy the requirement of 0mA~20mA, then need this antiskid brake control enclosure is improved, make it satisfy the follow-up test requirement.
Make the vibration value of shaking table reach value when breaking down, continue 25min at this value, comprise about 15min of performance test time of antiskid brake control enclosure, the antiskid brake working current that test antiskid brake control enclosure is exported should be 0mA~20mA; The vibration value that reaches when stepping reaches or when being higher than 18Grms, when the working current test passes, also the vibration value should be fallen after rise to 4Grms, the electric current of test antiskid brake control enclosure should be 0mA~20mA under little condition of shaking, and satisfies the requirement of follow-up vibration Step test;
According to the test profile of formulating, vibration step-length with 2Grms continues rising vibration value, continue 25min at the value that raises, comprise about 15min of performance test time of antiskid brake control enclosure, the antiskid brake working current of test antiskid brake control enclosure output should be 0mA~20mA; The vibration value that reaches when stepping reaches or when being higher than 18Grms, also the vibration value should be fallen after rise to 4Grms when the working current test passes, and the electric current of test antiskid brake control enclosure should be 0mA~20mA under little condition of shaking;
Require to proceed to 24Grms according to above-mentioned vibration Step test, 24Grms is the flutter failure limit value of determining before the test, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of test antiskid brake control enclosure output should be 0mA~20mA; When the working current test passes, also the vibration value should be fallen after rise to 4Grms, when the electric current of testing the antiskid brake control enclosure under little condition of shaking is in 0mA~20mA scope, off-test.
Described definite vibration test starting point is 4Grms~8Grms; The vibration step-length of determining is 2Grms; The retention time of determining every step-length vibration level is 25min, comprises about 15min of performance test time of antiskid brake control enclosure, and the antiskid brake working current of test antiskid brake control enclosure output should be 0mA~20mA; Determine to reach and when each vibration level finishes, carry out that 4Grms is little to shake behind the 18Grms; The antiskid brake working current that applies in the confirmed test process is 0mA~20mA; The value of determining sine sweep is 6Grms, and the frequency sweep frequency range is 10Hz~2000Hz.
The flutter failure ultimate value of described definite antiskid brake control enclosure is 22Grms; The flutter failure ultimate value of improved antiskid brake control enclosure is greater than 24Grms.
The value of described three kinds of antiskid brake control enclosure sine sweeps is 6Grms, the frequency of sine sweep is: 10Hz~2000Hz, the resonance frequency that test obtains is followed successively by: 150Hz~160Hz, 160Hz~170Hz, 150Hz~160, the resonance value that test obtains is followed successively by: 18Grms, 19Grms, 19Grms.
The present invention applies the antiskid brake working current when applying the vibration stepstress, whether the performance of test antiskid brake control enclosure is qualified, if the defective recommendation on improvement that then proposes, the vibration resistance ability of raising control enclosure, if qualified then the continuation tested, until meeting the requirements of the flutter failure limit.Adopt the broken circumpolar limit of vibration Step test test control enclosure vibration to belong to one of content of Highly Accelerated Life Test, be used for formulating the highly accelerated stress screen test profile.
The test parameters of the inventive method and implementation result are:
A. finish with 2 days time and excite antiskid brake control enclosure vibration fault hidden danger, propose recommendation on improvement and finish technological improvement; To the control enclosure checking improvement effect after improving, and proceed to vibrate Step test, until reaching designing requirement, three actual anti-vibration abilities that reach of embodiment are all greater than 24Grms;
B. in the process of flutter failure limit test, 5 apply working current set by step simultaneously, make trystate and use state consistency, under vibration stress, working stress acting in conjunction, excite the potential faults of control enclosure, in working order down, components and parts are in febrile state, excite easily and the hot relevant potential faults that shakes;
The present invention has reached the designing requirement that excites and eliminate vibration fault hidden danger, and making the antivibration ability of this control enclosure is greater than 24Grms by original increasing less than 22Grms.When reliability index MTBF is 6000h, according to GJB1407, need 6000h * 5 times=30000h just can inspire the identical potential faults that is sensitive to vibration at least.
The MTBF of embodiment 1 described control enclosure requires to be 6000h, after adopting the test method of vibration stepping to excite and improving the potential faults that is sensitive to vibration, carried out the reliability growth test of 30000h this year by GJB1407, apply high temperature, low temperature, temperature variation, vibration and work electric stress in the process of the test, do not break down in the process of the test, the innovative approach that proof is taked in 2 days test is effective, has the green effect of saving test period 30000h, reducing energy resource consumption.
The MTBF of embodiment 2 described control enclosurees requires to be 6200h, after adopting vibration Step test method improvement to be sensitive to the potential faults of vibration, carried out the reliability growth test of 31000h by GJB1407, apply high temperature, low temperature, temperature variation, vibration and work electric stress in the process of the test, do not break down in the process of the test, the innovative approach that proof is taked in 2 days test is effective, has the green effect of saving test period 30000h, reducing energy resource consumption.
The MTBF of embodiment 3 described control enclosurees requires to be 64000h, after adopting vibration Step test method improvement to be sensitive to the potential faults of vibration, carried out the reliability growth test of 32000h this year by GJB1407, apply high temperature, low temperature, temperature variation, vibration and work electric stress in the process of the test, do not break down in the process of the test, the innovative approach that proof is taked in 2 days test is effective, has the green effect of saving test period 30000h, reducing energy resource consumption.If when not vibrating Step test and corresponding design improvement before reliability growth test, according to fail-test experience in the past, reliability index needs to improve twice repeatedly at least in process of the test and just can reach designing requirement during greater than 6000h.Fail-test testing expenses hourly are 500 yuan, and 30000 hours testing expenses are 1,500 ten thousand yuan.In order to save time and resource, these three fail-tests adopt accelerated method to carry out, and the acceleration reliability test method of control enclosure is seen 201110443565.3 patent specifications.
Owing to adopted technique scheme, the present invention to have following characteristics:
A. adopt electric vibration table to carry out the flutter failure limit test of antiskid brake control enclosure, apply working current in the test process, the vibration fault hidden danger that obtains according to test proposes recommendation on improvement and finishes technological improvement;
B. will improve the definite flutter failure marginal test data in back as the data of formulating the highly accelerated stress screen test profile.
Existing vibration Step test method is compared with the technology of the present invention and is seen Table 1.
Table 1 existing vibration Step test method and the technology of the present invention contrast table
Description of drawings
Fig. 1 is the vibration Step test section of the embodiment of the invention 1;
Fig. 2 is the vibration Step test section of the embodiment of the invention 2;
Fig. 3 is the vibration Step test section of the embodiment of the invention 3;
Fig. 4 is the process flow diagram that the present invention vibrates Step test.
Embodiment
Three embodiment of the present invention adopt three kinds of control enclosurees on the different transporters to vibrate Step test respectively, by test with improve, make the control enclosure can operate as normal under the vibration environment condition of taking off, landing.And determine the vibration test parameter of highly accelerated stress screen section according to the state of the art after improving.
Test exemplar among three embodiment is all randomly drawed in the product of current payment, and the test exemplar is 1 cover.
Three flutter failure limit tests that embodiment carries out, the testing equipment of employing is the equipment of assay approval, and before the deadline, sees Table 2.
Table 2 testing equipment table
Embodiment 1
Present embodiment is that the antiskid brake control enclosure to first kind of homemade secondary-line-aircraft brake system carries out the flutter failure limit test, by vibration Step test and technological improvement, improves the vibration adaptation ability of control enclosure.
Present embodiment may further comprise the steps:
Step 1 is determined vibration Step test parameter
Described vibration Step test parameter is suitable for electric vibration table.
Step-length, the retention time on each step-length, the antiskid brake working current of the vibration value when described test parameters comprises on-test, vibration Step test, apply mode and test exemplar quantity, and the vibration test required value of vibration value when reaching 18Grms.
Vibration value when confirmed test begins is 4Grms.Determine that applying the step-length of vibrating Step test is 2Grms.Determine that the retention time on each step-length is 25min, comprise about 15min of performance test time of control enclosure
Determine the antiskid brake working current.Because the electric current of antiskid brake control enclosure output is directly proportional with the pressure of brake valve output, determines the antiskid brake working current according to the maximum brake pressure of brake valve output.
The brake pressure scope of brake valve output is 0MPa~20MPa, and the antiskid brake working current is 0mA~20mA.Apply the working current of mode for changing, the change frequency of this working current is 3 times/min; Nominal voltage is 28V, and in complete test profile, applies working current all the time.
When vibration value when reaching 18Grms and each later vibration level, when each vibration value finishes, and then vibration values is down to 4Grms and carries out little shaking, the components and parts rosin joint potential faults that in the high-magnitude vibration, inspires with timely discovery; About 15min of little time of shaking of 4Grms is as the criterion to carry out a performance test duration.When being lower than 24Grms, the flutter failure limit should finish the technological improvement that improves control enclosure antivibration ability, the technological improvement that can not improve control enclosure antivibration ability when the flutter failure limit is higher than 24Grms.
Test exemplar quantity is 1 cover.
Step 2 is formulated vibration Step test section
See Fig. 1 according to the test parameters formulation vibration Step test section that step 1 is determined.
The test profile horizontal ordinate of Fig. 1 top is the time, and unit is min; Ordinate is the vibration value, and unit is Grms, and the vibration value begins to finish to 24Grms from 4Grms.
Fig. 1 below is vibrational spectra, and horizontal ordinate is frequency, and unit is Hz; Ordinate is power spectrum density, and unit is g2/Hz.
Maximum brake pressure according to brake valve output is determined the antiskid brake working current.
In the present embodiment, the brake pressure scope of brake valve output is 0MPa~20MPa, and the working current of control antiskid brake pressure is 0mA~20mA.When the electric current of antiskid brake control enclosure output is 20mA, make brake valve export maximum brake pressure 20MPa; When the electric current of antiskid brake control enclosure output was 0mA, the brake pressure of brake valve output was 0MPa.Antiskid brake control enclosure output antiskid brake electric current is 0mA~20mA, and frequency of operation is 3 times/min; Nominal voltage is 28V; See Fig. 1.
Determine at the vibration retention time of each vibration level t
iThe vibration of=antiskid brake control enclosure stabilization time+test antiskid brake control enclosure required real time of output current, i=1~n.
Determine at the retention time of the little vibration level of each time t
j=test antiskid brake control enclosure required the real time of output current, j=1~m.
Determine to apply the duration of working stress, refer in complete test profile, apply working current.
Step 3 is installed the antiskid brake control enclosure
To test with the antiskid brake control enclosure on vibration table.During installation, bore four holes according to antiskid brake control enclosure installation site aboard at anchor clamps, the bore position symmetry is to reduce the error in the process of the test; In each hole, steel-wire screw-socket is installed then, steel-wire screw-socket is the steel material, the internal thread of steel-wire screw-socket is according to the mounting screw dimensioned of antiskid brake control enclosure, in order to the antiskid brake control enclosure is fixed on the anchor clamps, the purpose that steel-wire screw-socket is installed is not loosening in flutter failure marginal test process in order to guarantee the antiskid brake control enclosure, guarantees that the vibration value is unattenuated;
Use bolted on the moving-coil of shaking table vibration tong; Then the antiskid brake control enclosure is installed on the anchor clamps;
Cable is connected on the socket of antiskid brake control enclosure, the other end of cable links to each other with the test fixture of antiskid brake control enclosure;
A sensor is pasted at four jiaos of each angles at antiskid brake control enclosure loam cake, pastes 4 sensors altogether, is used for the test vibration value;
According to HB5830.5 Fig. 3 E level, adopt sine sweep to determine the resonance frequency of antiskid brake control enclosure.The frequency sweep frequency range is 10Hz~2000Hz, and the frequency of resonance determine to take place, and resonance occurs when frequency sweep proceeds to 150Hz~160Hz, and the resonance amplitude reaches 18Grms, and this resonant frequency point should be avoided in installation site aboard.In vibration sweep check process, the excited vibration value that applies is 6Grms.
Step 5, the test vibration breaking limit
By present embodiment step 3 the antiskid brake control enclosure is fastened on the moving-coil of shaking table with vibration tong, connects vibration transducer, the closing test chamber door.
The process of test vibration breaking limit is:
The initial value of shaking table is adjusted into 4Grms, the duration of vibration is 25min, the about 15min of performance test time that comprises the antiskid brake control enclosure, test the output current of antiskid brake control enclosure the first time, and the output current of described antiskid brake control enclosure is 0mA~20mA.
After first time end of test (EOT), according to the test profile of formulating, proceed to vibrate Step test with the step-length of 2Grms, vibrate value and be set to 6Grms, vibration duration is 25min, the about 15min of performance test time that comprises the antiskid brake control enclosure, test the output current of antiskid brake control enclosure the second time, and the output current of described antiskid brake control enclosure is 0mA~20mA.
After second time end of test (EOT), according to the test profile of formulating, proceed to vibrate Step test with the step-length of 2Grms, vibrate value and be set to 8Grms, vibration duration is 25min, the about 15min of performance test time that comprises the antiskid brake control enclosure tests the output current of antiskid brake control enclosure for the third time, and the output current of described antiskid brake control enclosure is 0mA~20mA.
Vibrate Step test according to above-mentioned test method, be increased to 18Grms until vibrating the step-length of value by 2Grms.
When the vibration value is increased to 18Grms, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, little time 15min that shakes.
Continuation rises to 20Grms with the vibration value of shaking table, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, little time 15min that shakes.
Continuation rises to 22Grms with the vibration value of shaking table, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, working current is 10mA after tested, does not reach the requirement that maximum output current is 20mA;
Antiskid brake control enclosure to the forfeiture brake function carries out technological improvement, makes it can export the antiskid brake working current of 0mA~20mA under the vibration condition of 22Grms, satisfies the antiskid brake functional requirement, makes it satisfy the follow-up test requirement.
In the present embodiment, when the vibration value of applying for the antiskid brake control enclosure when shaking table reaches 24Grms, if the antiskid brake working current of described antiskid brake control enclosure output does not satisfy the requirement of 0mA~20mA, then need this antiskid brake control enclosure is improved, make it satisfy the follow-up test requirement.
When shaking table gives vibration value that the antiskid brake control enclosure applies less than 24Grms, if the antiskid brake working current of described antiskid brake control enclosure output does not satisfy the requirement of 0mA~20mA, then need this antiskid brake control enclosure is improved, make it satisfy the follow-up test requirement.
Make the vibration value of shaking table reach value when breaking down, in the present embodiment, vibration value when the antiskid brake control enclosure that improves breaks down is 22Grms, so the vibration value of shaking table is adjusted into 22Grms, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested;
According to the test profile of formulating, vibration step-length with 2Grms continues rising vibration value, the vibration value that raises is 24Grms, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested; 24Grms is the flutter failure limit value of determining before the test, when the off-test during greater than this value of the flutter failure limit.
In the present embodiment, continue test and obtained the test figure of this antiskid brake control enclosure flutter failure limit greater than 24Grms, the VIBRATION DESIGN foundation is provided for design antiskid brake control enclosure, and flutter test data is provided for the integrated environment stress test of antiskid brake control enclosure, highly accelerated stress screen test.Main test data gathers and sees Table 3.
The invention allows for embodiment 2 and embodiment 3.
Described embodiment 2 and embodiment 3 are respectively the flutter failure marginal tests of certain type aircraft brake antiskid brake control enclosure, and the testing equipment that adopts is identical with employed testing equipment among the embodiment 1.
The process of embodiment 2 and embodiment 3 includes definite vibration Step test parameter, formulates vibration Step test section, control enclosure is connected on the vibration table, adopts sine sweep to determine the resonance frequency of this antiskid brake control enclosure, test vibration breaking limit, the antiskid brake control enclosure after the improvement is carried out each step of verification experimental verification by vibration tong, its detailed process is identical with the process of embodiment 1, difference is that embodiment 2 is different with the test data of embodiment 1 with test data among the embodiment 3, specifically is shown in Table 3.
Table 3 sine sweep and broad-band random vibration test antiskid brake control enclosure potential faults test parameters summary sheet
The various embodiments described above are that the antiskid brake control enclosure to three kinds of transporter brake system vibrates Step test, the flutter failure limit of test antiskid brake control enclosure in process of the test.Test objective is the vibration fault hidden danger that excites this antiskid brake control enclosure, and according to the vibration fault hidden danger proposition recommendation on improvement of determining, thereby reach the purpose of in about 2 days, finishing the excited vibrational potential faults and proposing the technological improvement suggestion, improve the vibration adaptation ability of antiskid brake control enclosure, and determine the vibration test parameter of highly accelerated stress screen section according to the state of the art after improving.
Test exemplar in the various embodiments described above is all randomly drawed in the product of current payment, can represent the quality level of current delivered product.In process of the test, break down and to carry out technological improvement and reparation, improve and repair the back and continue test.
Claims (4)
1. the method for an antiskid brake control enclosure flutter failure limit test is characterized in that concrete steps are:
Step 1 is determined vibration Step test parameter
Described vibration Step test parameter based on electric vibration table;
Step-length, the retention time on each step-length, the antiskid brake working current of the vibration value when described test parameters comprises on-test, vibration Step test, apply mode and test exemplar quantity, and the vibration test required value of vibration value when reaching 18Grms;
Step 2 is formulated vibration Step test section
According to the step-length of vibration value during on-test of step 1 and the test determined, vibration Step test, on each step-length retention time, antiskid brake working current and apply mode, when the vibration value reaches 18Grms and later little vibration test required value, determine vibration Step test section;
In the described vibration Step test section, the vibration value during on-test that the vibration value is set to determine, the output current of test antiskid brake control enclosure, this antiskid brake control enclosure output current should be 0mA~20mA; According to the vibration step-length of determining the vibration value of shaking table is elevated to next test point, the output current of test antiskid brake control enclosure, this antiskid brake control enclosure output current should be 0mA~20mA; At the vibration retention time of each vibration level t
iThe vibration of=antiskid brake control enclosure stabilization time+test antiskid brake control enclosure required real time of output current, i=1~n; At the retention time of the little vibration level of each time t
j=test antiskid brake control enclosure required the real time of output current, j=1~m;
Repeat the vibration-test process of described rising vibration value-this value of maintenance, the vibration value that imposes on the antiskid brake control enclosure until shaking table reaches the determined flutter failure limit;
Step 3 is connected the antiskid brake control enclosure on the vibration table by vibration tong;
Step 4 adopts sine sweep to determine the resonance frequency of this antiskid brake control enclosure
Carry out the sine sweep test according to HB5830.5 Fig. 3 E level, the frequency sweep frequency range is 10Hz~2000Hz, determines to take place the frequency of resonance, and this resonant frequency point should be avoided in installation site aboard; In vibration sweep check process, the excited vibration value that applies is 6Grms;
Step 5, the test vibration breaking limit
The antiskid brake control enclosure is fastened on the moving-coil of shaking table with vibration tong, connects vibration transducer;
The process of test vibration breaking limit is:
The initial value of shaking table is adjusted into 4Grms, the duration of vibration is 25min, the about 15min of performance test time that comprises the antiskid brake control enclosure, test the output current of antiskid brake control enclosure the first time, and the output current of described antiskid brake control enclosure is 0mA~20mA;
After first time end of test (EOT), according to the test profile of formulating, proceed to vibrate Step test with the step-length of 2Grms, vibrate value and be set to 6Grms, vibration duration is 25min, the about 15min of performance test time that comprises the antiskid brake control enclosure, test the output current of antiskid brake control enclosure the second time, and the output current of described antiskid brake control enclosure is 0mA~20mA;
After second time end of test (EOT), according to the test profile of formulating, proceed to vibrate Step test with the step-length of 2Grms, vibrate value and be set to 8Grms, vibration duration is 25min, the about 15min of performance test time that comprises the antiskid brake control enclosure tests the output current of antiskid brake control enclosure for the third time, and the output current of described antiskid brake control enclosure is 0mA~20mA;
Vibrate Step test according to above-mentioned test method, be increased to 18Grms until vibrating the step-length of value by 2Grms;
When the vibration value is increased to 18Grms, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, little time 15min that shakes; Continuation rises to 20Grms with the vibration value of shaking table, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, little time 15min that shakes;
Continuation rises to 22Grms with the vibration value of shaking table, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of antiskid brake control enclosure output is 0mA~20mA after tested, to vibrate value then falls after rise to 4Grms, the electric current of test antiskid brake control enclosure under little condition of shaking, working current is 10mA after tested, does not reach the requirement that maximum output current is 20mA;
Antiskid brake control enclosure to the forfeiture brake function carries out technological improvement, makes it can export the antiskid brake working current of 0mA~20mA under the vibration condition of 22Grms, satisfies the antiskid brake functional requirement, makes it satisfy the follow-up test requirement;
When the vibration value of applying for the antiskid brake control enclosure when shaking table reaches 24Grms, if the antiskid brake working current of described antiskid brake control enclosure output does not satisfy the requirement of 0mA~20mA, then need this antiskid brake control enclosure is improved, make it satisfy the follow-up test requirement;
When shaking table gives vibration value that the antiskid brake control enclosure applies less than 24Grms, if the antiskid brake working current of described antiskid brake control enclosure output does not satisfy the requirement of 0mA~20mA, then need this antiskid brake control enclosure is improved, make it satisfy the follow-up test requirement;
Step 6 is carried out verification experimental verification to the antiskid brake control enclosure after improving
Make the vibration value of shaking table reach value when breaking down, continue 25min at this value, comprise about 15min of performance test time of antiskid brake control enclosure, the antiskid brake working current that test antiskid brake control enclosure is exported should be 0mA~20mA; The vibration value that reaches when stepping reaches or when being higher than 18Grms, when the working current test passes, also the vibration value should be fallen after rise to 4Grms, the electric current of test antiskid brake control enclosure should be 0mA~20mA under little condition of shaking, and satisfies the requirement of follow-up vibration Step test;
According to the test profile of formulating, vibration step-length with 2Grms continues rising vibration value, continue 25min at the value that raises, comprise about 15min of performance test time of antiskid brake control enclosure, the antiskid brake working current of test antiskid brake control enclosure output should be 0mA~20mA; The vibration value that reaches when stepping reaches or when being higher than 18Grms, also the vibration value should be fallen after rise to 4Grms when the working current test passes, and the electric current of test antiskid brake control enclosure should be 0mA~20mA under little condition of shaking;
Require to proceed to 24Grms according to above-mentioned vibration Step test, 24Grms is the flutter failure limit value of determining before the test, continue 25min at this value, the about 15min of performance test time that comprises the antiskid brake control enclosure, the antiskid brake working current of test antiskid brake control enclosure output should be 0mA~20mA; When the working current test passes, also the vibration value should be fallen after rise to 4Grms, when the electric current of testing the antiskid brake control enclosure under little condition of shaking is in 0mA~20mA scope, off-test.
2. a kind of method of testing of the antiskid brake control enclosure flutter failure limit according to claim 1 is characterized in that, determines that the vibration test starting point is 4Grms~8Grms; The vibration step-length of determining is 2Grms; The retention time of determining every step-length vibration level is 25min, comprises about 15min of performance test time of antiskid brake control enclosure, and the antiskid brake working current of test antiskid brake control enclosure output should be 0mA~20mA; Determine to reach and when each vibration level finishes, carry out that 4Grms is little to shake behind the 18Grms; The antiskid brake working current that applies in the confirmed test process is 0mA~20mA; The value of determining sine sweep is 6Grms, and the frequency sweep frequency range is 10Hz~2000Hz.
3. a kind of method of testing of the antiskid brake control enclosure flutter failure limit according to claim 1 is characterized in that the flutter failure ultimate value of described definite antiskid brake control enclosure is 22Grms; The flutter failure ultimate value of improved antiskid brake control enclosure is greater than 24Grms.
4. a kind of method of testing of the antiskid brake control enclosure flutter failure limit according to claim 1, it is characterized in that, the value of described three kinds of antiskid brake control enclosure sine sweeps is 6Grms, the frequency of sine sweep is: 10Hz~2000Hz, the resonance frequency that test obtains is followed successively by: 150Hz~160Hz, 160Hz~170Hz, 150Hz~160, the resonance value that test obtains is followed successively by: 18Grms, 19Grms, 19Grms.
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CN110736595A (en) * | 2018-07-18 | 2020-01-31 | 中车株洲电力机车研究所有限公司 | Method for evaluating service life of electronic equipment in rail transit cabin |
CN110736595B (en) * | 2018-07-18 | 2021-08-17 | 中车株洲电力机车研究所有限公司 | Method for evaluating service life of electronic equipment in rail transit cabin |
CN109944648A (en) * | 2019-04-03 | 2019-06-28 | 中国船舶重工集团公司第七一九研究所 | Fluid excited vibration control method and device in a kind of lube pipe |
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