ASTM F1578-2007 Standard Test Method for Contact Closure Cycling of a Membrane Switch《薄膜开关的接触闭合循环用标准试验方法》.pdf

1、Designation: F 1578 07Standard Test Method forContact Closure Cycling of a Membrane Switch1This standard is issued under the fixed designation F 1578; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A num

2、ber 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 covers the setup, procedure, andapparatus required to depress and release a membrane switch toa predetermined number of

3、cycles.1.2 This test method also covers the optional use of speci-fied voltage and current during the cycling of the membraneswitch.1.3 This test method can be used in conjunction with otherASTM standards such as Test Method F 1596.1.4 This standard does not purport to address all of thesafety conce

4、rns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 2240 Test Method for Rubber PropertyDu

5、rometerHardnessF 1596 Practice for Exposure of Membrane Switches toTemperature and Relative HumidityF 1661 Test Method for Determining the Contact BounceTime of a Membrane SwitchF 1662 Test Method for Verifying the Specified DielectricWithstand Voltage and Determining the Dielectric Break-down Volta

6、ge of a Membrane SwitchF 1689 Test Method for Determining the Insulation Resis-tance of a Membrane SwitchF 1663 Test Method for Determining the Capacitance of aMembrane SwitchF 1680 Test Method for Determining Circuit Resistance of aMembrane SwitchF 2592 Test Method for Measuring the Force-Displacem

7、entof a Membrane Switch3. Terminology3.1 Definitions:3.1.1 contact closurethe event at which a specified resis-tance is achieved.3.1.2 duty cyclethe ratio of switch closed time to totalcycle time.3.1.3 test ratethe number of depressions and releasecycles per second.3.1.4 membrane switcha momentary s

8、witching device inwhich at least one contact is on, or made of, a flexiblesubstrate.4. Significance and Use4.1 This testing is performed to determine the electricalcontact reliability under switching conditions and the physicalchanges caused by mechanical actuation of the switch assem-bly in the env

9、ironments in which the assemblies operate.Evidence of deterioration, that is, cracking of substrate, domesboth metal and polyester, ink delamination, etc., resulting fromthis test can at times be determined by visual examination.However, the effects may be more readily ascertained bymeasurements mad

10、e prior to, during, and after exposure. Totalcircuit resistance, force-displacement, dielectric strength, insu-lation resistance, and capacitance are types of measurementsthat show the deleterious effects due to exposure.5. Apparatus5.1 Suitable Electronic Monitoring Device, to detect andcount conta

11、ct closure at a predetermined or specified test rateand duty cycle.5.2 Surface, flat, smooth, unyielding, and larger than theswitch.5.3 Test Probes, built to either of the configurations shownin Fig. 1 or Fig. 2, are acceptable but must be made of an inertelastomeric material with a hardness number

12、equivalent toA/45 65 as measured in accordance with Test Method D 2240.Test probes that do not meet this criteria must be specified andrecorded fully.5.4 Device, which will cycle the probe repeatedly into andaway from the switch at a specified test rate and duty cycle, andwhich is capable of providi

13、ng means for counting probe cycles.The motion of the probe should be perpendicular to the planeof the switch.1This 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 Dec. 1, 20

14、07. Published December 2007. Originallyapproved in 1995. Last previous edition approved in 2001 as F 1578 01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the sta

15、ndards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.5 Power Supply, capable of supplying specified voltage orcurrent, or both, if required.6. Procedure6.1 Pretest Setup:6.1.1 Secure the s

16、witch on a test table.6.1.2 Measure the Fmax and Fc in accordance with TestMethod F 2592 and any other desired characteristics of theswitch as specified in Section 7 and record.6.1.3 Position the test probe over the desired area of theswitch.6.1.4 Position the test probe until the tip is just above

17、the topsurface of the switch without touching.6.1.5 Connect the switch terminations to the contact closuremonitoring device, and power supply, if applicable.6.1.6 Adjust the probe in the full-down position to achieve110 % of Fmax or Fc (whichever is greater) or to a specifiedforce.6.1.7 Set the powe

18、r supply voltage or current to the speci-fied values, if applicable.6.1.8 Testing should be done under standard laboratoryconditions unless otherwise specified.6.2 In-Process Test:6.2.1 Begin cycling at specified test rate and duty cycle.6.2.2 Measure the characteristics of the switch at desiredinte

19、rvals as performed in 6.1.2.NOTE 1If switch removal from the test table is necessary, return theswitch to the exact location.6.3 End test:6.3.1 Stop the test at a preselected duration or at the point offailure.6.3.2 Measure the final characteristics using the samemethod, equipment, and conditions as

20、 used in the pretest setupdescribed in 6.1.2.7. Report7.1 Report the following information:7.1.1 Visual changes.7.1.2 Mechanical changes:7.1.2.1 Fmax, Fmin, Fc mandatory (Test Method F 2592)Other force displacement supporting data and curves optional.7.1.2.2 Contact Bounce Time Make membrane switchF

21、IG. 1 Test Probe OptionFIG. 2 Test Probe OptionF 1578 072ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such paten

22、t rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited eithe

23、r for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair he

24、aring you shouldmake your views known to the ASTM Committee 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 1578 073