ASTM F1997-99(2005)

Standard Test Method for Determining the Sensitivity (Teasing) of a Tactile Membrane Switch

SIGNIFICANCE AND USE
The tendency of a switch to make or break electrical contact at unexpected moments during closure or release can be a sign of a poor design. The degree of teasing can range from a simple annoyance to a failure of critical control process.
The amount of switch sensitivity or teasing can also be a result of poor surface conductivity that will prevent an electrical event even when switch poles are in partial contact.
SCOPE
1.1 This test method establishes procedures for depressing and releasing a tactile membrane switch to determine the amount of switch teasing, if any.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Dec-1999
• ICS: 31.220.20 - Switches
• Technical Committee: F01 - Electronics
• Drafting Committee: F01.18 - Printed Electronics

Relations

• Replaces: ASTM F1997-99 - Standard Test Method for Determining the Sensitivity (Teasing) of a Tactile Membrane Switch
• Effective Date: 10-Dec-1999

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:F1997–99(Reapproved2005)
Standard Test Method for
Determining the Sensitivity (Teasing) of a Tactile Membrane
Switch
This standard is issued under the fixed designation F1997; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.7 contact force (Fc)—the force at contact closure (see
Test Method F1597).
1.1 This test method establishes procedures for depressing
3.1.8 contact travel (Tc)—the travel at contact closure.
and releasing a tactile membrane switch to determine the
3.1.9 Fmin—minimum force seen between Fmax and point
amount of switch teasing, if any.
at which probe movement ceases.
1.2 This standard does not purport to address all of the
3.1.10 force-displacement curve—relationship between
safety concerns, if any, associated with its use. It is the
force applied and displacement of a membrane switch. Some-
responsibility of the user of this standard to establish appro-
times referred to as “force-travel curve”.
priate safety and health practices and determine the applica-
3.1.10.1 Discussion—usually expressed as a line graph.
bility of regulatory limitations prior to use.
3.1.11 force-resistance curve—the relationship between
2. Referenced Documents
force applied and resistance of a membrane switch.
3.1.11.1 Discussion—usually expressed as a line graph.
2.1 ASTM Standards:
3.1.12 membrane switch—amomentaryswitchingdevicein
F1570 Test Method for Determining the Tactile Ratio of a
which at least one contact is on, or made of, a flexible
Membrane Switch
substrate.
F1597 Test Method for Determining the Actuation Force
3.1.13 nontactile switch—a switch assembly that has a
and Contact Force of a Membrane Switch
tactile ratio equal to zero.
3. Terminology
3.1.14 return force (Frmin)—minimum force seen during
return cycle before reaching Frmax.
3.1 Definitions: Refer to Figs. 1 and 2 for the following
3.1.15 return max force (Frmax)—maximum force mea-
terms.
sured during return cycle after achieving Frmin.
3.1.1 actuation force (Fmax of Fa)—maximum force mea-
3.1.16 specified resistance—maximum allowable resistance
sured prior to or including point at which contact closure is
as measured between two terminations whose internal switch
achieved (see Test Method F1597).
contacts, when held closed, complete a circuit.
3.1.2 break force (Fb)—the force at contact break.
3.1.17 switch teasing (break)—the travel measurement on
3.1.3 break travel (Tb)—the travel at contact break.
the force-displacement curve between contact break (Fb) and
3.1.4 circuit resistance—electrical resistance as measured
return force (Frmin).
between two terminations whose internal contacts, when held
3.1.18 switch teasing (make)—the travel measurement on
closed, complete a circuit.
the force-displacement curve between contact force (Fc) and
3.1.5 contact break—point at which circuit resistance is
minimum force (Fmin).
higher than specified resistance.
3.1.19 tactile ratio—a measure of tactile response (see Test
3.1.6 contact closure (make)—point at which specified re-
Method F1570).
sistance is achieved.
3.1.20 tactile response—a sudden collapse or snapback of a
membrane switch prior to contact closure or after contact
This test method is under the jurisdiction of ASTM Committee F01 on
break.
Electronics , and is the direct responsibility of Subcommittee F01.18 on Membrane
3.1.21 tactile switch—a switch assembly that provides a
Switches.
tactile ratio greater than zero.
Current edition approved Jan. 1, 2005. Published January 2005. Originally
approved in 1999. Last previous approved in 1999 as F 1997–99. 3.1.22 Tb—travel at contact break.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3.1.23 Tfm—travel at Fmin.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3.1.24 Tr—travel at Fr.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
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F1997–99 (2005)
FIG. 1 Te
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