Note: Descriptions are shown in the official language in which they were submitted.
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ELECTPOSTATIC CHA~E S~PPi~ESSli~iG G~Ri~ENTS
Eicld_and_t'~clc~round_of_lnv~nli_n
This invention relates to garments which suppress
accumulation of electrostatic charges on the body of a
person wearing the garmcn-t.
Electrostatic charges accumulating on the bodie5
of persons have been recognized as presenting ha~ards
either to the persons or to industrial processes being
conducted in the presence of such persons. ey way of
examples, surgeons and nurses in operating theaters are
from time to time in the presence of explosive or
1 n potentially explosive atmospheres, in which a sparlc such
as can result from discharge of accumulated static
presents a signifTcant danger. For that reason, It has
been proposed to provide such persons with special
protective garments intended to suppress such charges.
Persons employed in "clean rooms" for the production of
mlcroclrcult components such as chips may, due to
electrostatic charges, either destroy components under
productTon or introduce contaminants such as dust.
For those reasons, it has been proposed to provide
special atmospher~s within such rooms in an attampt to
suppress electrostatic charges. Persons employed in
operations conducted near or adjacent sources of
electrostatic charges such as power lines may, due to
electrostatlc charges, be exposed to the possibility of
arcing over, or electrical discharge -i-hrough their
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bodies. As will be appreciated, in all such instances it is
desirable for the protection of either the persons or the process
that electrostatic charge accumulation be suppressed.
Brief Description of Invention
The invention provides a garment for suppressing accumu-
lation of electrostatic charges and comprising a body engaging
member and a knit fabric forming at least a portion of said body
engaging member, said knit fabric being formed oE yarn knitted into
courses and wales and including an electrically conductive strand
knitted with the yarn, wherein said yarn is knit into stitches
defining a ground and stitches defining loop pile extending from
the ground, and further wherein said conductive strand is knit
with stitches defining loop pile.
Garments are contemplated for engaging a number of
different body portions such as the torso, a foot, a leg, or a hand.
As will be pointed out more fully hereinafter, specific garments
may be selected for particular applications.
Brief Description of Drawings
Some of the objects of the invention having been stated,
other objects will appear as the
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description proceeds, when -i-aken in connection with the
accompanying drawings~ in which:
Figure 1 is a prespectlve view of a sandal
embodylng the present inventton;
Figure 2 is a sectional view through a strap of
the sandal of Figure 1, taken generally along the line
2-2 in that Flgure;
Flgure 3 is a sectional view simllar to Flgure 2,
taken genarally along llne 3-3 through the sole of the
sandal In Figure l;
Figure 4 is a perspectTve vtew of a woman's shoe
embodying the present invention;
Flgures 5 and 6 are sectlonal vlews through the
shoe of Flgure 4, respectlvely taken generally along the ~-
lInes 5-5 and 6-6 Tn that Figure;
FTgure 7 Is a perspective view of a man's shoe
embodylng the present Inventlon;
Flgure 8 Ts a sectlonal vtew slmilar to Flgures 3
and 5, taken generally along the llne 8-8 In Figure 7;
~ Figure 9 is a perspective view of an overshoe,
: : foot cover or bootie embodying the present Tnvention; `
; FTgure 10 Is a perspectlve, somewhat schematic,
~: vlew of a fabric as used In the garments of Figures
through 9;
: 25 ~ Ftgure 11 Is a schematic, enlarged perspective
vtew of the fabrlc of Ftgure 10;
Ftgures 12 and 13 are enlarged perspective vtews
slmtlar to Figure 11, respectively tal<en from the pTle
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face and the ground face of th~ fabric of Ftgure 10;
Figure 14 ts an elevatlon view of a hose embodying
the present invention;
Figure 15 ts a schematic, enlarged elevation view
of a portion of the hose of Figure 14, taken generally
along -i-he line 15-15 in that Figure;
Flgure 16 is an elevation view, partly
schematically broken away to represent fabric
constructlon, of a legwarmer in accordance with the
present Inventton;
Figure 17 Is a view similar to Figure 16, showing
a low rlse athletic sock embodying the present
inventlon;
~ Flgure 18 is a perspective vTew, partly
; 15 schematlcally broken away, of a mitt0n embodying the
present Inventlon;
Flgure 19 Is a sectional view taken generally
along the line 19-19 in Figure 18; and
~; Figure 20 is a view similar to Figure 18, showing
a:glove embodying the present invention.
Detailed DQscri4tl_n ~ In~ention
While the present invention will be described more
fuiiy hereinafter with reference to the accompanying
drawings, in which a preferred embodiment of the present
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:~ : of the:description which follows that persons of skill
:: in tne appropriate arts may modify the invention here
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this invention. Accordingly, tha description which
follo~s is to be understood as being a broad, teaching
disclosure directed to persons of skill in the
appropriate arts, and not as limiting upon the present
invention.
Referring now more particularly -to the
accompanying drawings, the present invention is shown
embodied in a number of different garments for
suppresslng accumulation of electrostatic charges, each
of which comprises a body engaging member. In Figures 1
through 9, to which a-ttention wTII first be direc-ted,
the body engaging member is in the form of a foot
engaging member, whlch may be a sandal (Figures
through 3), a woman~s shoe (Figures 4 through 6), a
man's shoe (Figures 7 and 8), or an overshoe, footcover
or bootie (Figure 9). Persons skilled in tha arts
relating to garments of this general class will be able
to recognize other types of foot engaging garments which
; may embody the present invention~ and it is contemplated
that any such garmen-t may use the present invention. It
is also contempla-ted that -the word l'garment" will here
be understood as beTng used with reference to any
articl~ of clothing or object which covers or engages
any portion of a person's body.
rhe sandal of Flgure 1, generally designat0d at
30, has a sole portton 31 and straps 32, 3~, 35; all of
whlch engage or contact the body of a wearer of the
sandal 30. In accordance with the present invention, a
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knlt fabric generally indicated at 3~ In Figures 2 and 3
forms at least a portlon of the body 0ngaging members of
the sandal 30. The knit fabrTc 36 has particular
characteristics as pointed out more fully hereTnafter,
such that electrostatic charges otherwTse possibly
accumulat1ng on the body of the wearer of the sandal 31~
are dTscharged or dissipated. In particular, the knit
fabrlc 36 is formed o~ yarn, preferably a synthetic yarn
such as polyes~er, knTtted into courses and wales. An
electrlcally conductive strand Is knitted with the yarn,
g7v1ng the fabrlc 36 its particular characteristTcs. The
yarn may be Icnit with a plaTn knit construction or may
be knlt with a plle knlt constructTon. In the latter
Tnstance, the conductlve strand may be knit wlth
stltches formlng the ground or base fabrlc from whtch
the plle extends, or may be knit wlth stltches forming
loop pile. Where a pile fabrlc Is used, placement of the
conductlve strand with the pile loops ~ay contrTbute to
~ maximlzatlon of the desired effects, and therefore may
be preferable.
The conductive strand used preferably Is a
synthetic monofllament yarn having electrIcally
conductlve characteristi C5 due to the inclusion of
conductlve materlals Tn the strand as extruded. Such
25 ~strands are available commerclally in the form of
mono~fllament nylon havlng carbon black extruded as a
bicomponent. Other forms of such conductive strands will
be known to persons of approprTate skill Tn the
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appllcable arts.
The woman~s shoe of Ftgures 4 through 6, generally
indicated there at 38~ may have the fabric 36 present in
an innerlining (Figure 5) and in a strap lining (Figure
6). Similarly~ the man's shoe of Figures 7 and 8,
generally indicated there at 39, may have the fabric
present in an tnneriining (Flgure ~). In each instance,
the presence of the fabric accompllshes the dlssipatton
or discharge of elecirostatic charges otherwlse possibly
accumulating on the body of the wearer of the shoe.
Lastly, wTth respect to the illustrated footwear, the
fabrlc 36 may be fabrTcated tnto an overshoe, footcover
or bootle as generally Indicated at 40 in Figure 9. Such
a footcover is particularly desirable for envlronments
In whlch persons may ordlnarlly expect to wear
conventlonal shoes, and yet statlc suppresslon Is
needed, as In an operatlng room or a clean room.
A fabrlc useful In the footwear constructlons
Illustrated and descrlbed to thls polnt Is shown In
20 ~Flgures 10 through 13. As there shown, the conductive
strands present in the fabric preferably are arranged,
due to the knlttlng process, In courses or bands In the
~abric. ~y spaclng such courses, a greater dlsslpatlon
effect Is achleved through the provlsion of more clearly
defIned pathways for the electrostatlc charges to follow
~In flowlng from the wearer's body. The fabrlc
~schematlcally Indlcated In Flgure 10 may be a plle
fabrlc, and may be constructed as shown more
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spectfically in Figures 11 through 13. There, a
conductlve strand is indicated at 41, while other yarns
knitted with the conductlve strand are indicated at 42.
FTgure 11 is included to indicate a typical stltch
construction, while Ftgures 12 and 13 are intended to
present an appearance more nearly approaching the actual
fabric as l<nlt. Persons skllled in the arts of knittTng
wlll be able to determine other knit fabric
constructions through whlch the advantages of the
present tnvention may be realized.
Garments embodying the present invention and
constructed to engage a leg are also contemplated by the
present tnventlon, as shown in Ftgures 14 through 17. As
; wlll be recognized by persons skllled in the appltcable
garment arts, such garments are oiten constructed of
kntt fabrlcs, and lend themselves admtrably to
applIcatlons of the present inventlon. In such garments
as the hose or half-hose illustrated in Figures 1~ and
at 44, the conductive strand or strands may be
Introduced into bands or courses 45 interspersed with
bands or courses 46 of other synthetlc or natural yarns
whlch are not conductive. As a consequence, static
otherwlse posstbly accumulattng on the body or clothing
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of a wearer of the hose 44 wtll be dlscharged to ground
25~ or dtsstpated, so as to avold such effects as sparktng
or~arctng, cllnglng clothing, and the Itke. Inasmuch as
tt ts relatlvely easy for a person to accumulate the
charge of approximately 2000 volts of electrostatTc
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dlfferential whlch gives rtse to sparlsing or arclng, as
many persons know from placlng a key to a lock or
shaklng hands after having walked across certain types
of carpet, avoidance of exploslons or other undeslrable
consequences of such dlscharges Is a result to be
apprec1ated.
Alternatives to the hose 44 of Flgure 14 are
contemplated as Includlng legwarmers as generally
Indlcated at 48 In Flgure 16 and low-cut socks as
generally Indlcated at 49 In Flgure 17. Each of these
alternatlve forms may have courses of conductlve strands
Interspersed wlth other courses 46 as descrlbed
above. Persons skilled In the arts of manufacturlng such
garments wtll be able to devlse stlll other leg engaglng
garments whtch wtll achteve the deslred result of the
present Inventlon.
Garments embodylng the present Inventlon may also
be constructed for engaging a hand, as suggested by the
mltten 50 of Figure 18 and the glove 51 of Flgure 20. In
each Instance, a fabrlc 36 has been employed, generally
; ~ as descrlbed above. In the Instance of the glove 51, the
glove Itself may be a plaln Icnlt fabrlc with the
conductlve strand knlt Into place, In order to achleve a
very thin glove useful In asslsttng entry into a rubber
25 ~glove such as used In a sterlle envlronment or wlthln a
controlled envlronment chamber. In the Instance of the
mltten 50, the yarn from whlch the mltten Is formed may
be a hlgh temperature yarn so as to make use of the
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mitten advantageous In such envtronments as foundrles or
steel mllls. As here used, "high temperature" means a
yarn which substantlally maintains structural integrity
and does not degrade at temperatures less than 550
degrees Fahrenheit. The phrase "structural integrity" is
Intended to mean maintainlng, upon reaching an elevateci
temperature, a tensile strength in the range of sixty
percent or more of the tensile strength at room
temperatures on the order of 70 degrees Fahrenheit.
"Degrade" is intended to describe melting, decomposition
or other loss of structural form. Examples of textile
fibers having the recited characteristics include aramid
fibers and polytetrafluoroethylene flbers.
; The fabrlc used in mittens as just described may
also be fabricated, using known technlques, into
garments resembling T shlrts for engaglng the torso of a
wearer. Such a proiectlve garment combines high
strength, thermal reslstance, and static suppression in
a partlcu!arly unusual and destrable way.
; In the drawlngs and specifications there has been
set forth a preferred embodiment of the invention and,
` although specific terms are used, the description thus
;~ given uses ter~linology in a generic and descriptive
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