Browse Prior Art Database

# Detecting Mechanical Motion

IP.com Disclosure Number: IPCOM000091687D
Original Publication Date: 1968-Apr-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 28K

IBM

## Related People

Davidge, RV: AUTHOR

## Abstract

This reed switch circuit is for detecting mechanical motion. Current through the coil of the electromagnet is reduced when the reed switch is closed thus decreasing the amount of mechanical motion necessary to effect opening of the reed switch. Current 1, flowing through the coil of electromagnet 10, produces a magnetic field which closes reed switch 11 when shunt material 12 is placed in proper position relative to the magnetic field created. When reed switch 11 is open, the steady state of current through the coil of electromagnet 10 is I(1) = (V/R1 + R2). When reed switch 11 is closed, the steady state current is reduced to 12 = V/(R1 + R2 + (R1)(R2)/R3). Diode 13 in series with R3 keeps current from flowing through load 14 when switch 11 is open.

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Detecting Mechanical Motion

This reed switch circuit is for detecting mechanical motion. Current through the coil of the electromagnet is reduced when the reed switch is closed thus decreasing the amount of mechanical motion necessary to effect opening of the reed switch. Current 1, flowing through the coil of electromagnet 10, produces a magnetic field which closes reed switch 11 when shunt material 12 is placed in proper position relative to the magnetic field created. When reed switch 11 is open, the steady state of current through the coil of electromagnet 10 is I(1) = (V/R1 + R2). When reed switch 11 is closed, the steady state current is reduced to 12 = V/(R1 + R2 + (R1)(R2)/R3). Diode 13 in series with R3 keeps current from flowing through load 14 when switch 11 is open. Relatively high current I(1) is used before switch 11 is closed so that it closes quickly as its magnetic circuit is completed by mechanical motion of shunt 12. The lower current 12 is used after switch 11 is closed so that it reopens quickly as its magnetic circuit is broken by mechanical motion of shunt 12.

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