Browse Prior Art Database

WATER PROOF SWITCH ASSEMBLY

IP.com Disclosure Number: IPCOM000007254D
Original Publication Date: 1994-Jun-01
Included in the Prior Art Database: 2002-Mar-07
Document File: 1 page(s) / 41K

Publishing Venue

Motorola

Related People

Jeff King: AUTHOR [+2]

Abstract

A very common problem encountered with port- able communication devices is waterproofing of the switches. This problem can easily be eliminated by to the decoder PCB. By totally thinning the plastic wall in the highlighted synch area, some increased attaching a strain gage (Sl), to the plastic housing, deflection will be generated assuming a constant nor- mal force. This deflection will be monitored by the in place of the mechanical or elastomeric switch. strain gage in the form ~of a change in resistance. The strain gauge can be molded into the plastic hous- The analog to digital converter (A/D) will then ing or simply bonded inside the plastic wall. Via change a value from zero to one at a certain preset wires, sockets or such other interconnect devices, resistance trigger point. The Micro-P in turn will the strain gage can then be electrically connected then activate the switching line.

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0 M MO-LA

Technical Developments Volume 22 June 1994

WATER PROOF SWITCH ASSEMBLY

by Jeff King and Osvaldo Romero !

A very common problem encountered with port- able communication devices is waterproofing of the

switches. This problem can easily be eliminated by

to the decoder PCB. By totally thinning the plastic

wall in the highlighted synch area, some increased

attaching a strain gage (Sl), to the plastic housing,

deflection will be generated assuming a constant nor- mal force. This deflection will be monitored by the in place of the mechanical or elastomeric switch. strain gage in the form ~of a change in resistance. The strain gauge can be molded into the plastic hous- The analog to digital converter (A/D) will then ing or simply bonded inside the plastic wall. Via change a value from zero to one at a certain preset wires, sockets or such other interconnect devices, resistance trigger point. The Micro-P in turn will the strain gage can then be electrically connected then activate the switching line.

ELECTRICAL SCHEMATIC

RI

+

s1 svi A/D - ~8 MICRO-P

124 0 Motorola, 1°C. 1994

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