Browse Prior Art Database

Garment for Magnetic Shielding of Wearer

IP.com Disclosure Number: IPCOM000112244D
Original Publication Date: 1994-Apr-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 59K

Publishing Venue

IBM

Related People

Angelopoulos, M: AUTHOR [+4]

Abstract

Disclosed is a garment made of high permeability materials which shields the wearer from magnetic fields. An important use is for cardiac patients fitted with electronic pace-makers which are prone to malfunction because of electromagnetic interference. Wearers of cardiac pace-makers must take care to avoid exposure to magnetic fields. There is a danger that the magnetic field will induce spurious voltages in the circuitry of the pace-maker which will cause unsynchronized heart muscle contractions that may lead to serious disruption of heart function. Alternating fields are of most concern because the induced voltage depends on d phi / dt but motion through a large inhomogeneous d.c. field can also cause problems.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Garment for Magnetic Shielding of Wearer

      Disclosed is a garment made of high permeability materials
which shields the wearer from magnetic fields.  An important use is
for cardiac patients fitted with electronic pace-makers which are
prone to malfunction because of electromagnetic interference.
Wearers of cardiac pace-makers must take care to avoid exposure to
magnetic fields.  There is a danger that the magnetic field will
induce spurious voltages in the circuitry of the pace-maker which
will cause unsynchronized heart muscle contractions that may lead to
serious disruption of heart function.  Alternating fields are of most
concern because the induced voltage depends on d phi / dt but motion
through a large inhomogeneous d.c.  field can also cause problems.
Implantable artificial hearts and other assist devices are being
designed with transcutaneous transformers for recharging the power
source [1].  It may also be necessary to shield these devices from
unintentional charging.  Lastly, there is concern for the long term
effects of exposure to low level a.c.  magnetic fields experienced by
utility workers.

      Disclosed is a garment made of a polymer which is loaded or
coated with a material having high magnetic permeability.  The
garment can be woven of filaments of a polymer which have been loaded
with mumetal (NiFeCu) powder or flakes.  The filaments are formed by
extruding the polymer/mumetal blend.  Alternatively, the garment can
be woven of a conductive polymer such as polyaniline or polypyrrole
and subsequen...