1、Designation: F 2188 02Standard Test Method forDetermining the Effect of Variable Frequency Vibration on aMembrane Switch or Membrane Switch Assembly1This standard is issued under the fixed designation F 2188; the number immediately following the designation indicates the year oforiginal adoption or,
2、 in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method establishes procedures for determiningthe effect of sinusoidal
3、 vibration, within the specified fre-quency range, on switch contacts, mounting hardware, adheredcomponent parts, solder or heat stakes, tactile devices, andcable or ribbon interconnects associated with a membraneswitch or membrane switch assembly.2. Terminology2.1 Definitions:2.1.1 contact closuret
4、he event at which a specified resis-tance is achieved on a membrane switch.2.1.2 critical resonance frequencyany point on the speci-men that is observed to have maximum amplitude or more thantwice that of the base input amplitude or support points.2.1.3 membrane switcha momentary switching device in
5、which at least one contact is on, or made of, a flexiblesubstrate.2.1.4 specified resistancemaximum allowable circuit re-sistance as measured between two test points whose internalcontacts, when held closed, complete a circuit.2.1.5 test pointstwo pre-selected conductive points in acircuit loop, pos
6、sibly including a switch.3. Significance and Use3.1 Vibration encountered in the field is not usually simpleharmonic.3.2 This test can be used to determine relative motionbetween parts, critical frequencies, adhesion strengths, loosen-ing of parts or other physical effects that can cause fatigue orf
7、ailure.3.3 Experience has shown that this test will expose potentialfailures associated with the electronic components of a mem-brane switch, where tests of lower levels will not.3.4 This practice can be used to qualify a membrane switchfor aerospace, medical and other applications.3.5 This test is
8、potentially destructive, intended for devicequalification.3.6 Either Test Condition A or B can be chosen, based uponthe intent of the test determined by the qualified engineer.4. Apparatus4.1 Vibration Fixture, capable of holding the unit under testand subjecting it to the specified random frequency
9、 andduration as described in the In-Process Test.4.2 Contact Closure Detection Device, (if test is performedunder load conditions), instrumentation capable of resolving aswitch opening time of greater than or equal to 1.0 ms.4.3 Resonant Detecting Instrumentation, (if determinationof critical resona
10、nce frequency is desired), capable of deter-mining the critical resonance frequency.5. ProcedureTest Condition A, 10 g5.1 Pre-Test Setup:5.1.1 Secure membrane switch on vibration test surfacewith appropriate fixturing.5.1.2 Connect switch detection leads to test points on themembrane switch (if cont
11、act closure is being monitored duringthe test).5.1.3 Function testing to be specified and performed againafter test completion for comparison.5.2 In-Process Test:5.2.1 Subject test unit to sinusoidal vibration varied infrequency from 10 to 500 Hz at a logarithmic rate of 0.5 octaveper minute for a d
12、uration of 18 cycles per each orthogonal axis(total of 56 times). The amplitude of the vibration shall beeither 0.06-in. double inch amplitude or 10 gravities (g-peak),whichever is less. The tolerance for the vibration profile is63dB.5.2.2 Visual inspection shall be conducted after each axis ofvibra
13、tion.5.2.3 Electrical and functional testing shall be specified bythe qualified engineer and performed at either test completionor between each axis of vibration.5.2.4 A failure shall occur if parts show signs of mechanicalfatigue, cracking, excessive rubbing or loosening of the sup-porting hardware
14、 A failure should also be designated if contact1This test method is under the jurisdiction of ASTM Committee F01 onElectronics and is the direct responsibility of Subcommittee F01.18 on MembraneSwitches.Current edition approved May 10, 2002. Published July 2002.1Copyright ASTM International, 100 Ba
15、rr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.closure occurs during vibration and or electrical or otherfunctional testing provides unsatisfactory results.6. ProcedureTest Condition B, 20 g6.1 Pre-Test Setup:6.1.1 Secure membrane switch on vibration test surfacewith a
16、ppropriate fixturing.6.1.2 Connect switch detection leads to test points on themembrane switch (if contact closure is being monitored duringtest).6.1.3 Function testing to be specified and performed againafter test completion for comparison.6.2 In-Process Test:6.2.1 Subject test unit to sinusoidal v
17、ibration varied infrequency from 10 to 500 Hz at a logarithmic rate of 0.5 octaveper minute for a duration of 18 cycles per each orthogonal axis(total of 56 times). The amplitude of the vibration shall beeither 0.06-in. double inch amplitude or 20 gravities (g-peak),whichever is less. The tolerance
18、for the vibration profile is63dB.6.2.2 Visual inspection shall be conducted after each axis ofvibration.6.2.3 Electrical and functional testing shall be specified bythe qualified engineer and performed at either test completionor between each axis of vibration.6.2.4 A failure shall occur if parts sh
19、ow signs of mechanicalfatigue, cracking, excessive rubbing or loosening of the sup-porting hardware. A failure should also be designated if contactclosure occurs during vibration and or electrical or otherfunctional testing provides unsatisfactory results.7. Report7.1 Report the following informatio
20、n:7.1.1 Description of vibration equipment used,7.1.2 Description of mounting fixture including drawing,diagrams, and photos as necessary,7.1.3 Functional testing results before and after test,7.1.4 Describe Test Condition used, either A or B,7.1.5 Description of the visual fatigue of any components
21、 orhardware,7.1.6 Contact closure event (if monitored), when occurredand axis being tested,7.1.7 Temperature,7.1.8 Relative humidity,7.1.9 Barometric pressure,7.1.10 Part number or description of switch, or both, and7.1.11 Date of test.8. Keywords8.1 contact closure; frequency; membrane switch; vibr
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25、mmittee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).F 21882
