1、Designation: F 2112 02Standard Terminology forMembrane Switches1This standard is issued under the fixed designation F 2112; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicate
2、s the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This terminology defines terms that are commonly usedin the membrane switch industry.1.2 These definitions are not mutually exclusive.2. Terminologyactuation forcet
3、he maximum force measured prior to orincluding point at which contact closure is achieved on amembrane switch.bendto force from a straight form into different and espe-cially a curved one.bend cyclea fold of a sample around a specified mandrelwhich is “rolled” in one direction, followed by rolling i
4、n theopposite direction, returning the sample to its originalposition.circuit resistanceelectrical resistance as measured betweentwo test points whose internal contacts, when held closed,complete a circuit.conductor resistancethe measured electrical resistancethrough a circuit loop between two test
5、points.contact bounceintermittent contact opening and contactclosure that may occur after switch operation.contact closurethe event at which a specified resistance isachieved on a membrane switch.contact forcethe force at contact closure.creasea ridge or groove made by folding and pressing.crease cy
6、clea 180 degree crease followed by a flattening ofthe crease.current carrying capacitythe maximum level of electricalcurrent that a circuit can conduct without sustaining damage.dielectric withstand voltagethe maximum voltage a dielec-tric can withstand in a membrane switch without a visualchange fr
7、om a voltage discharge or specified change ofinsulation resistance, or both.duty cyclethe ratio of switch closed time to total cycle time.graphic layeroptional decorated layer of a membraneswitch. See Fig. 1.insulation resistancethe electrical resistance between twoisolated test points on a membrane
8、 switch.leakage currentcurrent flow through the insulation betweentest points.membrane layera flexible dynamic layer which carries oneor both switch poles the deflection of which is used to shortboth poles together. The membrane layer is a requiredcomponent of a membrane switch. See Fig. 1.membrane
9、switcha momentary switching device in whichat least one contact is on, or made of, a flexible substrate.membrane switch flex tailflexible portion of a membraneswitch used for input/output connection.nontactile switcha switch assembly that has a tactile ratioequal to zero.open circuit resistanceminim
10、um allowable resistance asmeasured between two test points that, if lower than, willindicate an electrical short.power capacityelectrical power is defined as current 3voltage = V 3 I (watts)rigid layerprovides mechanical support for the membraneswitch. See Fig. 1.silver migrationa process by which s
11、ilver, when in contactwith insulating materials under electrical potential, is re-moved ionically from its original location, and is redepositedas a metal (silver dendrite) at some other location.spacer layera material (usually dielectric) sometimes usedto maintain a separation between the membrane
12、layer andstatic layer of a membrane switch.specified circuit resistancemaximum allowable circuit re-sistance as measured between two terminations whose inter-nal contacts, when held closed, complete a circuit.static layera mechanically supported layer which carriesone or both poles of the switch or
13、is used to short both polestogether. The static layer is a required component of amembrane switch. See Fig. 1.tactile layeroptional feature incorporated into a membraneswitch to alter the tactile response. See Fig. 1.tactile responsea physical sensation caused by a suddencollapse and/or snapback of
14、a membrane switch.tactile switcha switch assembly that provides a tactile ratiogreater than zero.test pointstwo preselected conductive points in a circuitloop, possibly including a switch.travelmeasured distance of movement when a membraneswitch is depressed.1This terminology is under the jurisdicti
15、on of ASTM Committee F01 onMaterials for Specific Applications and is the direct responsibility of SubcommitteeF01.18 on Membrane Switches.Current edition approved March 10, 2002. Published May, 2002. Originallypublished as F 2112-01. Last previous edition F 2112-01.1Copyright ASTM International, 10
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19、ve not received a fair hearing 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 multipl
20、e 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).FIG. 1 Six Basic Layers of a Membrane Switch (Layers are shown as separate components but some can be combined into one layer. Forexample a graphic layer can also be the membrane layer. A second example is the tactile layer can also be the membrane layer.)F21122
