Note: Descriptions are shown in the official language in which they were submitted.
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Background of _~he_ Invent~on
Field of the ~nvention
Thls invention relates to protective channel or conveyance
systems for conduits, and more partlcularly, but not by way of
llmltatlon, to corru~ated sheathing systems for loosely receiv-
lng electrlcal conductors extended between remotely spaced lo-
catlons.
Brlef Description of the Prior Art
The Natlonal Electrlcal Code ln use in the United States
contalns certain speclfic and exacting provisions rela~ive to
the types of power cable and electrical conduits whlch can be
used in certaln wiring situatlons and cable conveyance situ-
ations, and lncludes speclflcations and criterl~ to be observed
in encaslng conductor~, electrical wires ~nd cablo~ within cer-
taln nonmetalllc jackets enclosln~ condults. Such spec1flcatlonsapply to both surface extensions of cables or conductors in
which the cables or conductors and surrounding nonmetallic jackets
are mounted directly on the surface of walls or celllnn, and
also aerial extenslons in whlch a supportina cable is used to
hano or suspend a cased or jacketed electrical cable or conduc-
tor. The jackets required for the accommodation of such
electrical cable and conductors are, of course, in addition to
belnq nonmetallic, ~lexible so that~the necessary turns or bends
required to carry the cable over a predetermined course can be
utllized. Good flexibility is thus required of the jacket or
conduit which is to contain the electrical cable. It is further
required, of course, that where the nonl~etallic jackets or
conduits are arranaed in end-to-end relation to extend the total
lenath thereof, fittinos used for connections shall be such that
3U the electrlcal conductors are not exposed b~twee~ the len~ths of
~he conduits or at the fittinss. It ls al~o requlred th~t at ~he
terminal point of each conductor, a fittln~ or box which com~
pletely covers the end of the assembly ~hall be u6ed.
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3~9~3
~ 2
As a result of certain limitations of structural strength
believed to characterize such nonmetallic conduits as t~,ose
made of Dolyvinyl chloride and other thermoplastic materials,
the specifications of the code require that conduit havino a
nominal diametric size of 1~2 inch through one inch be supported
at intervals which do not exceed 3 feet between points of su?-
port. Also, in order to avoid short circuiting and fire
hazards, the brackets used to support spans of the enclosing
conduits are required to be attached to woodwork or plaster,
and are not permitted to contact any metalwork or other
electrically conductive material. Other requirements exist
for aerial cable assemblies suDDorted upon a messenger line
or cable.
In the case of metallic conduits or raceways used to carry
electrical conductors, it is required that contact with similar
metals (by the metallic raceway) be avolded in order to eliml-
nate the possibility of the occurrence of galvanic action.
Also, certaln restrlctions are provided upon the manner ln
which metallic raceways can be placed in contact with, or
buried in, the earth. These restrictions are based upon the
possibility of deterioration under conditions of corrosion and
rusting.
Due to the propensity of such metal raceways to crimp or
become distorted when they are bent through angles of 90 or
more, the code speclficatlons requ~re that installations which
lnclude such bends avoid crimping of the raceway in a manner
whlch will reduce the effective internal diameter thereof. To
this end, limitations are placed on the slze of the radius of
curves deflned by the inner edge of the metallic raceway in
certain installations.
In certaln types of installations whlch use rigid metallic
conduit, the material of which the conduit or raceway is con-
structed, must be flame retardent, resistant to impact or
crushing, resistant to distortion from heat under condltlons
likely to be encountered ln ~ervice, and resistant ~o sunlight.
It must also, when used under~round, be resl~tant to molsturo
and corro lve agent~, and 3u~f~c~ntly btr~ng to w~h~n~ abu~,
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such as by impact or crushin~ loads. Rinid nonmetallic conduit
or raceways are required to be supported along their len~th at
each three foot interval in the case of one-half inch to one
inch diameter conduit, and supDorted at from flve up to about
eight foot intervals for six inch diameter conduit. Bends made
in such rigid nonmetallic conduit are also required to be formed
in such a way that no crimpin~ or reduction in internal dia-
meter of the conduit results.
In Australian Patent 155,417, an electrical wirin~ system
is disclosed suitable for installation in building structures,
and includes at least one central conduit box and a plurality
of tubular conduits extending from the box for receiving insul-
ated electrlcal conductors. The tubular conduits ln Pach case
include at least one relatively short piece of corru~ated
flexible tubing, and at least one relatively lon~ piece of rigid
tubing co~nected in a relationshlp such that there is a pl~ce of
the flexible tublng interposed between the condult box and the
adjacent end of a piece of the rlgid tubing. The ends of the
rlgid tubin~ are threaded suitably to form a threaded interlock
with the corrugations of the flexible Qections of tubing.
U.S. Patent 3,936,417 to Ronden is directed to a poly-
vinyl chloride pipe or conduit which is sufficiently flexible
to permit it to be coiled up for transport and handlin~
purposes, but has sufficiently high impact and tensile strength
to satlsfy the most stringent requirements for commercial
nstallation. The composition prescribed in this patent also
has a hl~h distortlon temDerature.
In some lnstances, such as in a flexible cable shield
developed by IBM and disclosed ~n the IBM Technical Disclosure
Bulletln, Volume IX, No. 2, July of 1966, flexible corrugated
cable shlelds or conduits have been made in two semicylindrical
parts which can be folded lnto a cylinder abou~ an lnterconnec-
tlng hinqe, or couples together by pairs of matlng ~lange~
located at opposite sides of the two semlcyllndrlcal ~art~.
A modular cellular condu1t assembly conslstln~ of a
plurallty of corrugated conduit or pipe sections adapted for
use as an underground lnstallation ~or car~ying talophon- lln~-,
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electrical llnes and sim~lar conductors is described in U.S.
Patent 3,693,664. The individual corru~ated pipe or conduit
sections used in the assembl~ are each flexible to facilitate
shipment and installation.
A desi~eratum which existed for a number of vears, and
was aIlegedly solved in 1955 by t~e patentees in U.S. Patent
2,728,356, was the fabrication o~ a large diameter, thln
walled flexible plastic tubina. A diffic~lty which existed
with tublng of that sort as it had been previously provided
was that when subjected to bending, it tended to undergo
buckling or crimping, thus undesirably reducina the internal
diameter of the tubinq. The ~atentees proposed to overcome
the problem by providing a plurality of contiguous corrugations
in the tubing in which the minimum radius curvature of any
lS portion o~ the ridges and valleys of the corru~ations of the
tubing was at least three times the wall thic~ness at that
portlon of the corruqated tublng. The patentees provlded,
moreover, that the crest of the ridges and valleys of the
corrugations must constltute lon~ arcs of at least 150, and
not more than 270. The ridges and valleys of the corrugations
were each arcs formed about a radius many times the thickness
of the tubing wall. Further, the patent~es contemplated that
in the most preferred form~ the ridaes and valleys of the
corrugatlon have an identical radius. This allegedly resulted
in uniform dlstribution over a wide area of the stresses aris1na
from bending of the flexib}e tube~ without a concentration of
stress in any one narrow zone.
U.S. Patent 3,060,069 dlscloses a plastic corrugated
tublng useful for enclosing electrical conductors, and parti-
cularly of value in providing heat lnsulatlon for high resist-
ance electrical conductors.
A corrugated flexible conduit whlch can be transversely
flexed or bent without danger of collapsing or crlmplng, bu~
whlch ls incapable of undergolng axlal stretch, 1~ dlsclo~ed ln
35 U.S. Patent 2,891,581. Thls tublna, however, 1~ made o~ a
rubber composltion.
An objectionable characteristic of many types of
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corrugated tubing propo6ed as raceways or sheaths for electricalconductors in the prior art is that after bendins through a
relatively short radius, a tendency exists for the tubino to
sDrinq back or to underao a reduction in radius of curvature
at the bend location due to the elasti.c properties of the
material, and the nature of the corruqations formed therein.
This difficulty ls allegedly overcome by the partlcular
material of construction used in a corruoated tubing having
unconventlonal corru~ations therein, as shown and described
in U.S. Patent 3,908,704. In short, the side walls of each
corru~ation are o unequal lenath, or stated differently, the
principal axis of each corruoation extends at an acute angle
to the lon~itudinal axis of the tubing or conduit in which the
corrugations are formed. ~his enables each corruqation to
fold in under an adjoinina corrugation without kinkln~ or
reductlon in the effective internal ~iameter of the tublng when
bends are made on a very small radius. A sultable plastlc of
which this tublng may be made ls flexlble polyvlnyl chlorlde.
It is polnted out in the patent that where the corrugated tubing
ls used as a cable or harnessed dielectrlc for conductors, a
substantial advantage is obtained as a result of the very nood
dielectrlc properties of the plastic of which the tublng is made.
U.S. Patent 3,132,415 indicates it as a criteria of
corrugated electrical sheathing or conduits that such conduits
be manually coilable in bends of various radii which can be as
short as flve times the outside d~ameter of the conduit if
necessary. It is also desirable that the condult be sufficiently
reslllent that it can be restored to its origlnal straight form,
without residual bend deformations as it is lnstalled. The
conduit has hiah impact resistance (of the order of 0.9 foot-
pounds per inch accordin~ to ASTM D-256). The corrugated conduit
or conductor made in accordance with thi~ patent is said to be
capable of readily elono,ating and contracting wlth temperature
chanqes, without bowing out between pointq of support, or
buckling at ~upports. Moreover, the conduit can elon~ate or
shorten a brldae members move as a re~ult o expan~lon or
contraction, wlthout any harm belng ~on~ to th~ a~embly,
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~ corrugated e~ectrical conduit for containin~
electrical conductors is disclosed in ~.S. Patent 3,892,912.
In this conduit, the corrugations have flat trou~hs and crests
which extend parallel to the axis of the conduit, and the side
S walls of each of the corrugations are of equal length. ~he
crests, however, are of greater len~th, as measured longitu-
dinally along the conduit, than are the troughs
The standards and specifications established by
Underwriters Laboratories for rigid nonmetallic conduit~
constructed of polyvinyl chloride, polyethylene and similar
materlals require that the conduit be used at a temperature
not hlgher than 50C with ~iring rated, ln any case, not
higher than 90C. The specifications further provide that
such conduit or fittin~s shall provide a smooth internal
raceway for the pulling in of wires and cables, and that
such conduits shall not be threaded. For a so-called heavy
wall PVC conduit, specifications of Underwriters Laboratory
requlre that a wall thlckness ranging from 0.109 to 0.129
lnch be character~stlc of conduit having a nominal 1/2 inch
dlameter, and that a wall thickness rangin~ from 0.28 to
0.314 be characteristic of heavy wall PVC conduit having a
nom~nal diameter of 6 inches. ~or a so-called thin-walled
PVC conduit, the 1/2 inch conduit must have a wall ~hickness
ranglng from 0.060 to 0.080 inch. Four lnch conduit of the
thin-walled type must have a wall thickness of from 0.15 to
0.1~ inch.
The Underwriters Laboratory specifications further
require that elbow bends in a conduit effected throuqh
connectlon of elbows to a straight section of the conduit be
such that the bend is free of kinks and creases. It is
further requlred that for this straight walled, noncorruqated
conduit, no bends shall be sharper than 90. For a 1/2 inch
conduit, the radius of a bend in the conduit can be no
smaller ~han four lnches. For a ~ix lnch condult, the
radius needs to be no smaller than thl~ty lnches. For all
types of PVC conduit, the tens~le 3trength must ~e not lesR
than 5,500 pounds per square inch The Epeclflc~tion~ ~nd
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standards of Underwriters Laboratory further provide certain
crushing specifications: For ~xample, a l/2 inch stralght
wall condui~ must not undergo a r~duction of more than 30
in its internal diameter when a 3iX inch 5pec imen of the
conduit is subjected to a 1000 pound loading imposed upon
the central portion conduit. For th~n walled PVC conduit,
the same reduction in internal diameter rnust not be exceeded
when a load of 300 lbs. is centrally im~)sed upon a ~ix inch
specimen. For a six inch diameter conduit, the specified
reduction in internal diameter must not be exceeded under a
load of 850 lbs. in the case of the heavy-wall~d conduit.
Certain impact strength reguirements are also imposed upon
both the heavy-walled and thin-walled conduit.
Corrugated conduit suitable for underground burial and
for the containment and conveyance of telephone cables and
the like is manufactured and marketed under the trademark
"CORFLO~ by Haskon, Inc. o~ Middletown, Delaware. The
CORFLO underground corrugated duct l~ claim~d to have high
crush resistance, and high flexlbili~y which allows elbows
and bends to be easily form~d in the duct. The CORFLO
corrugated duct is made of high density polyethylene, and is
sold in sizes of from 1 1/2 inches up to 4 inches. The
impact resistance of the CORFLO polyethylene corrugated duct
ranges from about 40 foot-pounds for 1 1/2 inch duct up to
about 150 foot-pounds for 4 inch duct as determined by ASTM
D-2 4 4 4-7 0 TUP B .
Brief Description Of The Present_Invention
There is provided a system for suppvrting and conveying
electrical conductors canprising: at least one elongated,
syn~hetic resin tubular corrugated conduit havlng ex~ernal
annular corrugations extending therearound; and a ~ynthetic
resin sleeve for clampingly engaging such conduit includ-
ing: elongated, axially extending, radially movable corru-
gated clamping elements movable relatlve to each other for
closure abou~ the tubular corrugated conduit, and including
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arcuate corrugations dimensioned and configured to engage
and register with the corrugations of said ~ubular corru-
gated conduit; and means r~leasably converging said cl~mping
elements to retain said clamping elem~nts in a closed posi-
tion in engagement with said conduit, with the corrugationsof said clamping elements engaged with the corrugations of
~a id condui t .
There is also provided a synthetic resin connector clamp
for interconnecting two ~ections of corrugated tubing to
each other in end-to-end relation comprising: a medial
cylindrical body portion having a smooth outer peripheral
wall; a f irst split-jawed clamping portion connected to one
end of the cylindrical body portion; a second split- jawed
clamping portion connected to the opposite end of said body
portion from said first split-jawed clamping portion; each
of said first and second split- jawed clamping portions
comprising: at least one movable ~aw having an end flexibly
connected to an adjacent end of said body portion to facili-
tate movement of the jaw from a position in which it extends
parallel to the axis of the medial cylindrical body portion,
to a position in which it extends at an angle thereto, said
movable jaw having a plurality of arcuate corrugations
thereon each lying in a plane extending normal to the axis
of the medial cylindrical body portion, and conduit-
receiving means secured to said adjacent end of the bodyportion and defining a generally cylindrical structure with
said movable jaw when said movable jaw is positioned
parallel to the axis of the medial cylindrical body portion;
and means 51 idably mounted on said body portion and slid-
ably engageable with said movable jaw to move said jaw intoa position parallel to the axis of said medial body portion
when said means slid~bly mounted on the body portion is
axially moved along the body portion and onto the movable
ja~ and the conduit-receiving means.
The above system is useful particularly, though not
exclusively, for conveying, supporting and connecting electri~
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cal servlce cables and wires betwe~n ~eparated locations of
supply and service. The system includes a unique, corru-
gated, synthetlc resln ~ondult which may be very flexible
and mechanically qulte strong, b~t which may be thin-walled
and llght, so that it can easlly be manually manlpulate~ and
lnstalled. The above connector sleeves or cla~ps may be
used for clamping sectlons of the corr~gated condul~ ln end-
to-end relatlon to prevent axial ~lippase, and the system
may lnclude hanger sleeves for clamping the condult in a
non-slip engagement, and suspending it from a wall or simi
lar ~urface. The connector sleeves and hanger sleeves can
be made of electrlcally non-conductive material. T~e sys-
tem may lnclude ~ novel electrical outlet box which lncludes
internally toothed, conduit-receivinq inlet flttings inte-
lS grally f~rmed in the box for securely engaging ends of thecorrugated conduits with inlets to the box by interfitting
and physlcal interference between the corrugations of the
condult and the internally toothed, conduit-receiv~ng inlet
flttings.
The preferred flexlble, synthetic resin condult can be
manually bent to a relatively sharp bend of low radlus without
the elastlc memory of the materlal of construct~on of the con-
duit resulting in lts positlonal deviatlon, after bending, in
the dlrection of lts original configuration.
The preferred form of flexible conduit of synthetic resln,
though capable of being manually bent into a varlety of conflg-
urations involvlng relatively sharp bends, can be suspended at
spaced locations on a wall or other supporting structure in
such a way that lt w~ll undergo a relatively small deflection
from llnearity when so suspended, and when carrying electrical
cables or condult.
Preferably, the condult 18 a rlgld polyvlnyl chlorlde
corrugated condult which has a relatively ~hln wall (ranglng
fro~ a~out 0.1 inch ~o about 0.2 lnch), but has ~ h~h lmpact
35 6trength and hiqh cru~h re~istsnce. Thl~ conduit can be bent
through bends havlng B ra~iu~ a~ ~mall ~ four ~h~- wl~ho~t
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crimping or undergoing any reduction in internal diameter.
The tensile strength of the PVC corrugated conduit is prefer-
ably in excess of 5000 pounds per square inch.
The preferred system of flexible conduit and fittings
can be bent into various shapes to permit its installation
in a great variety of locations requiring changes of direction
of the conduit, and can be very quic]cly and easily installed
as a result of the manner in which the fittings utilized
with the conduit cooperate with the conduit as a system
is installed.
In accordance with the present invention there is
provided a connector sleeve for interconnecting elongated
sections of conduit comprising a split cylindrical section
of tubular conduit including a semi-cylindrical first part
having opposed, parallel longitudinal edges, a semi-cylindrical
second part having opposed, parallel, longitudinal edges,
hinge means interconnecting said semi-cylindrical first
and second parts at a longitudinal edge of each for folding
of the first and second parts toward and away from each
other between an open position and a closed position; and
constrictable strap means cooperating with said first and
second parts to retain said parts in a closed cylinder array.
Additional advantages will become apparent as the
following detailed description of certain preferred embodiments
of the invention is read in conjunction with the accompanying
drawings which illustrate such preferred embodiments.
General Description of the Drawinqs
Figure 1 is a view in elevation of one arrangement
of a system of flexible conduit and fittings of the invention,
and illustrating in section, a wall to which a portion of
the system is mounted, and an electrical box forming a portion
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oE the system.
Figure 2 is a detail view illustratiny, in section,
the manner in which an end portion of the corrugated conduit
forming a part of the system is engaged by a conduit-receiving
inlet fitting used at an inlet opening in an electrical box.
Figure 3 is one form of hanyer sleeve, constructed
in accordance with the present invention, and forming a part
of the flexible conduit and fittings system of the invention.
Figure 4 is a perspective view of one different form
of connecting clamp whic~ can be used in one embodiment of
the conduit and fitting system of the invention and illustrating
this connector clamp as it appears when opened apart preparatory
to receiving the opposed end portions of a pair of sections
of corrugated conduit disposed in end-to-end relation.
Figure 5 illustrates the connecting clamp shown in
Figure 4 as it appears when it is in its closed position,
and as it is used in conjunction with synthetic resin closure
straps forming a part of the connector clamp.
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Fi~ure 6 is a persOective view of yet another form of
connecting clamp useful in another e~.bodiment of the system of
the invention, and illustrating this connectin~ clamp as i~
appears when it is o~ened to its conduit-receiving position.
Fi~ure 7 is a pers~ective view of the connectin~ clamp
shown in Fi~ure 6, illustratinq this clamp as it apDears when
it is in its closed, conduit-enaaging position.
Figure 8 is a perspective view of a form of connector
sleeve which forms a part of the system of flexible conduit
and fittings of the presen~ invention.
Figure 9 is a sectional view taken through the longitudinal
axis of the connector sleeve shown in Figure 8.
Figure 10 ls a modified embodiment of the connector sleeve
illustrated in Figure 8.
Figure 11 is a sectional view taken along the lon~itudinal
center llne of the connector sleeve shown ln Fl~ure 10.
Flgure 12 ls a perspectlve vlew of another embodlment of
a connector clamp useful ln the present lnvention and show~nq
the clamp ln lts opened position.
Fiaure 13 is a perspective v~ew of the connector clamp of
Figure 12 showing the clamp in its closed positlon.
Fiaure 14 is a sectional view through the connector clamp
shown in Figure 13, and showin~ in section a pair of corrug~ted
condult sectlons clamped thereby.
Figure 15 ls a side elevation view of another form o
lnlet flttlng used ~n terminating~a corrugated conduit at an
openlna lnto an electrlcal box in the system of the lnvent~on.
~lgure 16 is a vlew partlally ln elevation and partlally
in section of the inlet fitting illustrated in F~gure lS, and
showlng, in section, a portlon of an electrical box in which
the lnlet fitting is mounted, and in dashed lines, a retainer
bushin~ used to mount the fitting ln the box.
Referrlng inltl~lly to Flgure 1 of the dr~wing~, th3 ~lexlble
3S conduit and fltting system o~ the lnventlon lnclude~ ~ ~lurallty
of lengths or sectlons 10 of corrugated condult. ~h~ corrugste~
-- conduit sections 10 each have a longltudlnal cro~s-~-ctlon~l
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conflguration as illust~ated in Ficure 2 of the drawin~s, and
preferably include a series of corruaations havina relativel~
sharp crests lOa which are interconnected by relatively sharp
or V-shaped troughs lOb. The corrugated conduit 10 is prefer-
ably constructed of polyvinyl chlorid~ which is of the typereferred to in the industry as rigid polvvinyl chloride,
contains at least 80 percent vinyl chloride, and is prefera~ly
one of the types referred to as Type 1 or Type 2 in the
specifications set forth in AST~l-D-1784-75. The corruaated
conduit 10 can be of varying diametric size, includino conduit
havin~ a diameter of up ~o six inches, but preferablv is
between 1/2 inch and 1 inch in diameter.
The wall thickness of the conduit, as measured normal to
the plane of one of the wall sections extending from a trough
lS to a crest of one of the corrugations, is preferably about
0.1 inch to about 0.13 inch in the case of the 1/2 inch
dlameter conduit, up to a wall thickness, as similarly measured,
of from about 0.13 lnch to about 0.20 inch in the case of the
1 inch dlameter conduit. This relatively thin wall thlckness
characteristic of the corrugated conduit, when constructed of
a riald polyvlnyl chloride, permlts the lenaths of the conduit
to be bent freely and easily by hand from a linear confiouration
to a selected confiauration in which the hend in the conduit
may define an an~le as small as 90 or less. In most instances,
however, installatlon requirements will not require bends
greater than 90~. In such cases,~the condult can be bent upon
a relatively small radius, lf deslred. For example, conduits
wlthln the preferred diametric slze range of from 1/2 inch to
1 inch can be easily bent upon a 4 inch radius without crimping
or reduction of the lnternal diameter of the conduit, and
without fatigulng, stressing or crac~lng o~ the tensioned,
radially outer wall of the conduit.
In the particular arranoement of the sy~tem lllustrated in
Flgure 1, several forms of fitting component~ URed ln the ~ystem
are il~ustrated, and a novel sy~thetlc resln electrieal box 11
adapted to recelve and securely enoage free end~ o~ the ~on~ult
ls lllustrated. Referrlnq lnlti~lly tO the ol~ctrlcal bo~
~L~3~3
- 13 -
such is here shown as b~ina a junction box rather than a
service box, and is used for receivino a plurality of elect-
rical conductors extended throu~h the flexible corruaated
conduits. Thus, a Dair of conductors 12 and 14 are extended
through one of the conduit sections, with the conductor 14
then being extended into a second conduit section alonq with
conductor 16 originatin~ in vet a third conduit section. The
three conduit sections which carry the conduits 12, 14 and 16
to the interior of the electrical box 11 are joined to side
walls 18 of the box through conduit-recei~ing inlet fittings,
designated generally by reference numeral 20, ~which are pressed
into conduit openings in the side walls of the box.
Each of the inlet fittings 20 comprises an annular element
havinn an axially extending annular flange 22 which aradually
narrows in thickness to a relativel~ sharp outer ed~e, and
whlch has a peripheral, radially inwardly extendin~ aroove 24
formed therearound. The groove 24 is sized to receive a
clrcular edge of a side wall 18 of the box at the locatlon
where a larae circular inlet opening is formed in the respec-
t~ve slde wall. The ~nlet fitting 20 is thus interlocked bysnap engagement with the respective ~ide wall 18 of the box 11.
Such snap enyagement is easily effected by pressin~ the fittina
from the inside of the box outwardly, and usina the wedging
actlon afforded by the tapered outer side of the annular flange
22 to force the side wall to a position where it will snap into
the groove 24.
Each lnlet fittlng 20 further includes a radially inwardly
extending receptor plate 26 which carries a centrally apertured
hub 28 at the radially inner slde thereof. The hub 28 has a
large openlng formed through the center thereof, and the opening
is defined and surrounded by a plurality of annular serrations
or sawtooth type ~rooves whlch are dimensloned to ~losely
register with the corruaatlons in the flexlble condult section~
10. This engagement is illu~trated ln Figure 2 of the drawlng~.
Sufficient flexibllity characterizes each of the inlet f1tttngff
20 and the end portion of each of the condult sectlons 10 to
permit the end of the ~onduit to ~e ~orc~d through tho op~lng
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- 14 -
ln the hub 28 of the fi~ting, and into registering snap engaae-
ment with the serrations formed around the central openi~c in
this hub. Each condult section 10 i5 thus positively inter-
locked with the electrical box 11.
S It will be understood that a suitable cover (not shown)
is provided for closure of the electrical box 11 after the
electrical conductors carried within the corrugated conduits
10 have been projected into the electrical box, and desired
connections to, or changes of direction of, the conduits have
~een effected within the electrical box 11, as may be required
by the particular lnstallation.
The corrugated flexlble conduit sections 10 utilized in
the system of the invention are, in many conventional installa-
tions, required to underso one or more bends of 90, and to be
su~ported in a horlzontal course at vertical elevations on
walls, or ln a particular vertical course up the side of a
wall. This type of arrangement is illustrated in Fiaure 1,
where lt wlll be noted that three of the right angle bends,
which can be easily accomplished by manual manipulation of
the sectlons 10, are lllustrated Figure 1 of the drawings
also illustrates a novel hanger sleeve 30 which can be used
in conjunction with the corruqated condult sections 10 for the
purpose of supportin~ a conduit section in a fixed position on
a wall~
The hanger sleeve 30 ls illustrated in detail in Figure 3.
This structural element is fabricated from an electricallv non-
conductive synthetic resln, and preferably is rigid polyvinyl
chloride of character similar to that of which the flexible
conduit lO is manufactured. The hanger sleeve 30 includes a
semi-cyllndrical body port~on 32 which is jolned at one longi-
tudinal edge to a first suspension flange 34 and at ~he other
longitudinal ed~e to a flat side wall 36 whlch is secured to,
and formed integrally wlth, a second suspenslon flange 38
posltloned ln substantially ~oplanar all~nmen~ wlth the fl~t
slde wall~
The ~ody portion 32 carries on the lnner side wall thereof
a first serles of axially spaced, radi~lly lnwasdly p~oj~ctin~
,,
~3~9;~3
-- 15 --
triangularly cross-sect~oned ribs 40 along one side thereof,
and a similar second series of ribs 42 on the opposite si~e
thereof. The ribs 40 and 42 are ~eometrically confi~ured to
register with the corrugations in the flexible conduit sections
10 at such time as the han~er sleeve is closed about a section
of the flexible conduit to brina the ribs 40 and 42 into mating
engagement with the corrugations of the conduit section. The
closed portion of the hanger sleeve 30 is illustrated in Figure
3. It will further be noted in referring to Figure ~ that the
suspension flanges 34 and 38 each carry facing, interlockin~
serrations or ribs 44 and 46, respectively, and that these
interlockinn ribs cause the suspension flan~es, when in
abutting registering contact, to lndex screw-receivino aper-
tures 50 formed through the suspe~sion flanges in alignment
with each other.
In use, the hanger sleeve 30 is first opened by separatln~
the ~uspension flange 34 and 38 sufficlently to permit an inter-
medlate portion of a section 10 of the corrugated flexible
cond~it to be inserted between these flanqes, and lnto the body
portlon 32 of the hanger sleeve. The hanaer sleeve 30 is then
closed about the conduit by pressing the suspension flanges 34
and 38 into reglsterin~ contact with each other. The character
of the synthetic resin material of which the hanoer sleeve 30
is constructed assures that such closure will firmly clamp the
hanger sleeve about the conduit section 10. After such engage-
ment of the hanger sleeve with the conduit section 10, a suitabl~
screw 42 can be inserted through the aligned screw recelving
apertures 50 in the suspension flanges 34 and 38 and into a wall
54 or the like to mount or hanq the flexible condult section on
the wall at thls locatlon in the manner illustrated in Fiaure 1.
In Figures 4 and S of the drawlngs, one form of connector
sleeve 59 used ln the system of the present inventton is
illustrated. The connector sleeve lncludes a spllt cyllndrical
corrugated section of tubing wh~ch lncl~des a semlcylindrlc31
first part 60 and a semicylindrlcal second part 62. The
corruga~ed semicylindrical parts 60 and 62 are ~o~ned by a
flexible, medial hinge section 64, and a p~lr of end hlng~
,~
:~36~3
- 16 -
sec~ions 66 and 68 whic~ are each spaced longitudinally from
the medial hinge section. The hinge sections permit the parts
60 and 62 to be folded about an axis extending longitudina11y
along the center line of the several alligned hinged sections
so that the two parts may be moved from an open position, as
shown in Flgure 4, to a closed position as shown in Figure S.
It will be noted in referring to Figures 4 and 5 that each of
the semicylindrical parts 60 and 62 has a plurality of contig-
uous, axially arranged circumferential corrugations 70 formed
therealong, and these corrugations are dimensioned and shaped
to faciltate registry with the corrugations of corrugated
conduit sections 10.
When the two parts 60 and 62 are folded abo~t the hinge
portions 64, 66 and 68 to a closed position as shown in
Figure 5, spaces are provided bet~een the end hinge ~ortions
66 and 68 and the medial hinged portion 64. These two spaces
facilitate the accommodation of a pair of flexible straps or
bands 72 and 74. The straps ~2 and 74 include respective end
portions 72a and 74a which carry lnwardly facing teeth~76.
The teeth 75 engage, throuah a ratchet action, a tongue carried
on the lnside of engaging blocks 78 and 80 which are secured to
the ends of the respective straps 72 and 74. This structure
facilitates the tight securement of the straps 72 and 74 about
the closed, semicylindrical Darts 60 and 62 of the sleeve 59 to
retain it ln its closed position.
In the use of the connector ~leeve, the opposed facina
ends of a pair of conduit sections 10 are placed within one of
the parts 60 or 62 of the connecting sleeve, and the respective
conduit sections then project from opposlte ends of this sleeve.
After placement of the corrugated conduit sections 10 in a
posltion in which the corrugations in the two sections mate or
register with the corresponding corrugatlons 70 on one of the
semicyllndrical parts 60 or 62, the other part ls then closed
about the facing corrugated conduit sections to tiahtlv ~ngage
the palr of conduit sectlons over a ma~or portion of thelr
periphery through reglstration of the corrugations. The ~tr~p~
72 and 74 are then placed around th~ conne~tor sleeva ~ ~hown
... .
~ r ~ .l
:1~3~
- 17 -
in Figure S and are tigh~tened about the connector sleeve and
the enclosed conduit section by pulling the end portions 72a
and 74a through the gau~ina blocks 78 and 80 until a tisht
securement is effected.
It should be pointed out that the connector sleeve S9
shown in Figures 4 and 5 can also be used as a hanger sleeve
for suspending or supporting a section of the corrugated
conduit on a wall or ceilina. Where such usage of the sleeve
is employed, suitable screws or nails are extended throuqh
the end portions 72(a) and 74~a) of the straps 72 and 74, and
into the wall or ceilin~ to hanq or suspend the sleeve at a
selected location, and with it the conduit section which
extends through the sleeve. It will be apparent, of course,
lS that the sleeve 59 shown in Fi~ures 4 and 5 can also function
dually as a connector sleeve and as a han~er 51eeve. This is
to say that a pair o~ the corrugated conduit sections 10 can
be placed with thelr end portions secured within the sleeve in
end-to-end relation, and both sections can then be supported
or suspended on a wall or celling in the manner describe~.
In Figures 6 and 7 of the drawings, a modified embodiment
of connector sleeve 81 is illustrated. As ln the cvnnector
sleeve embodiment shown in Fiqure 4, a pair of semicylindrical
parts 84 and 86 are utillzed, and these part~ are ~nterconnected
by a flexible hinqe portion 88 which extends alons, and inter-
connects, the opposed, adjacent lQngitudinal edges of the semi-
cylindrical parts. The hinge portion 88 is suff1ciently
flexlble that the semicylindrical parts 84 and 86 can be opened
apart to the position shown in Flqure 6 to facilitate the inser-
tion of a pair of conduit section ends withln one of the semi-
cylindrical parts in the manner prevlously described.
In the embodiment of the connector sleeve 81 shown in
Figure 6, the semicylindrical part 86 has form~d lntegrally
thereon, and adjacent one of the longltudinal edge0 of the part,
a palr of strap engaqing blocks 90 and92. The engaglng block~
90 and 92 function similarly to the blocks 78 and 80 prevlou~ly
described in referring to the connector sleeve embodiment of
~.......................... .
.
Figures 4 and S, and thus serve to receive and engage the tooth-
carrying end portions of a pair of flexible straps 94 and 96.
The flexible s~raps 94 and 96 are formed inte~rally with the
semicylindrical part 84 and project therefrom at a location
adjacent one of the lon~itudinal ed~es of this part of the
connector sleeve. When the connector sleeve 81 is in its
closed position, it appears as shown in Figure 6. It will be
understood, of course, that prior to closing the connector
sleeve, one or a pair of corrugated conduit sections is inserted
between the semlcylindrical parts 84 and 86 which function to
effect interconnection of two sections, or to support a sing~e
corrugated section or a pair of sections placed in end-to-end
relation.
In Figures 8 and 9, another embodiment of connector clam~
or sleeve 99 used in the system of the present invention is
illustxated. The connector sleeve 99 includes d central or
medial cylindrical body portion 100 which has smooth outer and
lnner wallR, ~nd whlch ls connected at its opposite ends to a
pair of spllt jawed clamping portions designated ~enerally by
reference numberals 102 and 104. Each of the split jawed
clamping portlons 102 and 104 is substantially identical to the
other, and each includes a pair of movable jaws 106 and 108
which are hlngedly connected by hlnges 110 and 112 to one end
of the central body portion 100 along a medial or arcuate seg-
ment of a circle. The movable jaws 106 and 108 can movet in a
pivotal motion, outwardly with re~pect to the axis of the
connector sleeve.
Each of the movable jaws 106 and 108 on the opposite ends
of the connector sleeve carries a plurality of internal arcuate
corrugations 109 which are shaped and dimensioned to register
with the corru~ations in one of the corrugated conduit sections
10. Each of the movable jaws is also provided on its outer
periphery with a relief or recess 113 whlch lles between a p~lr
of shoulders 114 and 116 formed on the outer side of the respec-
tive movable jaw. It wlll be noted tha~ the ~houlder 114 15
formed by the abrupt termination of an axially 310plng, arcuatc
ri~ 115 which slopes inwardly toward th~ body portlon 100. ~ha~
portlon o~ each of the movabl~ ~AW~ lOG ~n~ 108 ly~g ~Cw~n
, .i.
12~
- 19 -
the rib 115 and the respective hinge llG and 112 by which the
jaw is connected to the~Central body portion 100 is ~mooth, and
constitutes a segment of the outer periphery of a cylinder.
Positioned on opposite sides of the connector sleeve 99
S from each other, and between each opposed pair of movable
jaws 106 and 108 are a pair of rigid, axially extending scmicylin-
drical side walls 120 and 122. Each of the side walls 120 and
122 has a smooth outer peripheral surface formed on a segment of
a cylinder, and each has internal corrugations 123 which are lo-
cated to occupy a position of axial alignment with the corruga-
tions 110 in the movable jaws when the movable jaws are closed
as hereinafter explained. The corrugations 123 on the side wall
120 and 122 are also dimensioned and configured to register with
the corrugations of the corrugated conduit sections 10.
Slidably mounted on the connector s}eeve 99 for axial sliding
movement therealong are a pair of annular collars 126 and 128.
Each of the annular collars 126 and 128 is of rectangular cross-
section, and each collar has a transverse dimension which is
slightly smaller than the transverse dimension which is cha~acteris-
tic of the recess 113 as measured axially along the connector sleeve
99 .
As shown in Figure 9, the collars 126 and 128 can be slid
axially along the connector sleeve 99 so that either or both of
the collars pass over the respective arcuate ribs 115 on the
movable jaws 106 and 108 at one end of the connector sleeve and
snap into the recesses 112. In this manner, the movable jaws 10
~Z3(~LP3
- ?o -
and 108 are forced to a position of closure s~ch that, with the
rigid side portions 120 and 122, they form a closed cylinder,
the interior of which is lined by the corrugations 109 and 123
carried on the movable jaws and rigid wall portions.
A different embodiment of the connector sleeve used in the
system of the invention is shown in Figures 10 and ll of the
drawings. The connector sleeve 130 here illustrated is similar
in many respects to the connector sleeve embodiment shown in
Figures 8 and 9, and identical reference numerals have been
utilized for identifying identical parts of the sleeve. It will
be noted in referring to Figure 11 that the central cylindrical
body portion 100 of the connector sleeve 130 shown in Figure ll
is somewhat shorter than the central body portion 100 o~ the
sleeve embodiment shown in Figure 9. As in the case of the
earlier described connector sleeve, the central body portion
130 has smooth outer and inner walls, and has slidably mounted
around the outer periphery thereof a pair of annular collars
126 and 128.
The collars 126 and 128 can slide freely along the central
body portion 100 and out over a pa~r of split jawed clamping
portions, designated generally by reference nu~erals 132 and 134,
and located at the opposite ends of the central body portion.
Each split }awed clamping portion 132 and 134 is substantially
ldentical to the other, and each includes a pair of movable jaws
136 and 138. Each of the movable jaws 136 and 138 ls hingedly
.
.. . . _ . .
~ ;~3l?~ '3
- 21 -
connected to the central body portion 100 in the mdnner ~rc-
viously described, and each jaw carries a series of internal,
arcua~e corrugations 140 which are shaped and dimensioned to
register with the corrugations in each of the corrugated con-
duit sections 10. Each of the movable jaws 136 and 138 is
also provided on its outer periphery with a relief or reccss
142 which lies between a pair of shoulders 144 and 146. It
will be noted that the shoulder 146 is formed by the abrupt
termination of an axially sloping, arcuate rib 148 which
slopes inwardly toward the body portion. That portion of each
of the movable jaws 136 and 138 lying between the rib 148 and
the respective point of hinged connection of the jaw to the
central body portion is smooth, and constitutes a segment of the
outer periphery of a cylinder.
Positioned on oposite sides of the connector sleeve 130
from each other, and between each pair of opposed movable jaws
136 and 138, are a pair of rigid, axially extending semi- .
cylindrical side walls 150 and 152~ Each of the side walls 150
and 152 has a smooth outer peripheral surface formed as a segment
of a cylinder, and a smooth inner~peripheral surface similarly
for~ed
Projecting inwardly from the internal wall of the central
body portion 100 at a location which is substantially midway
between the points of hinged connection of the jaws 136 and 138
to the central body portion is an annular, radially inwardly
~L~3~ 33
- 22 -
projecting stop f}ange 154.
In the use of the connec-or s1eeve 130 shown in Fi~rcs l0
and 11, the end portions of a pair of corruga,ted conduit sections
10 are inserted into opposite ends of the connector sleeve 130
S until the end face of each corrugated conduit section abuts against
the radially inwardly projecting stop flange 154. With the corru-
gated conduit sections 10 thus aligned-in end-to-end relation,
and abutteù against the stop flange 154, the annular collars 126
and 128 can then be slid axially along the connector sleeve 130
until these collars pass up over the axially sloping, arcuate
ribs 148 and into the respective recesses 142 carried on each of
the movable jaws 136 and 138 at opposite ends of the connector
sleeve, The corrugated conduit sections are thus clamped firmly
within the connector sleeve in end-to-end relation as previously
lS described.
Another form of connector clamp useful in the system of
the invention is illustrated in Figures 12-14, and is designated
generally by reference numeral 160. The connector clamp 16Q
includes a split body which is made up o~ a first split body
portion 162 and a second split bo~y portion 164. The split
body portion 162 is characterized in having a semicylindrical
internal wall 166 which has a radially inwardly projecting,
arcuate, semicylindrical stop rib 168 formed centrally thereon.
On its outer side, the split body portion lfi2 has a substantial}y
planar surface 170 formins one side wall and intersecting another
.
~ ;~3CJ~3
- ~3 ~
substantially planar su~ace 172. The surfaces 170 and 172 are
joined by a longitudinally extendiag, radiused corner 174 ~hich
extends substantially parallel to the axis of the se~ic~lindrical
internal wall 166.
At the side of the surface 170 opposite its intersection
with the radiused corner 174, a slot or groove 178 is formed
in the body portion 162, and this slot or groove is slightly
undercut as shown at 178b in Figure 13. A final element of the
body portion 162 is an axially extendlng block 1~0 which projects
from one end of the body portion to the other, and on its inter-
nal side defines a portion of the semicylindrical inner wall 166
of the ~ody portion. The block 180 includes a facing surface
180b which is beveled or cut along a plane which lntersects at
an angle, the plane in which a corresponding facing s~rface 186
lS lies on the opposite side of the body portion 162.
The body portion 164 of the connector cla~p 160 ls formed
similarly to the body portion 162, and thus lncludes an internal
semicyllndrical wall 182. The internal semicylindrlcal wall 182
of the body portion 164 has a radially inwardly extendingl
arcuate semicylindrical stop rib 184 formed centrally thereon
and in alignment with the arcuate semicylindrical stop rib 168
formed on the body portion 162. On opposite sides of the stop
rib 184, and at locations spaced axially along the internal
: semicylindrical wall 182 of the body portion 164, a pair of
25 radial slots 188 and 190 are formed through the body portion,
and each slot is provided with a reduced transverse dimension
adjacent the outer side of the body portion (not visible) in
order to retaln an internally flanged locklng plate 192 which
is slidably posItioned in each of the radial slots 188 and 190.
It will be noted, as hereinafter described, that the loc~ing
plates 192 can slide radially in the slots 188 and 190, and
each carries a radially inner edge whlch is dimensioned to
facilitate engagement with corruqatlons of the corrugated
conduit sections 10 as shown in Flgure 14 and herelnafter
described.
The semicylindrical inner wall 182 of the body portlon 164
terminates at its opposlte lonal~udlnal edges ~t a p~lr o~
9~3
- 24 -
coplanar surfaces 196 and 198. The plane ~n which the surfaces
196 and 198 lie extends ~hrough the center of the cylinder upon
which the semicylindrical inner wall 182 is formed. It should
be pointed out that the synthetlc resin used for interconnecting
the body portions 162 and 164 forms a hinge 200 about which
these body portions may be folded to open and close the connec-
tor clamp as hereinaf~er described.
Connected to the external side of the body portion 164
which is connected to the hinge portion 200 is a locking band,
designated aenerally by reference nu~eral 202. The locking
band 202 is generally L-shaped in confiauration, and includes
a first leg 204 secured by a thin hing~ portion 206 to the body
portion 164, and a second leg 208 which is secured at substan-
tially a ri~ht angle to the leg 204. The legs 204 and 208 are
joined through a radiused corner 210 which conforms in its
radius of curvature to a radiused corner 212 formed along a
longitudlnal edge at the outerside of the body portlon 164. At
the free end of the leg 208 (that ls, the end opposlte its side
connected to the leg 204), the leg 208 carries a latching rib
210 which is configured to snap into, and register with, the
groove 178 ln the manner illustrated in Figure 13.
In the use of the connector clamp 160, as shown in Figure
14, the end portions of a pair of corrugated conduits 10 are
placed in end-to-end relation, with one side of the conduits
in contact with the semicylindrical inner wall 182 of the body
portion 164, and the end faces of the two conduit sections
abutting the stop rib 184. The body portion 162 is then folded
about the upper side of the two conduit sections 10 until the
surface 180b is adjacent and faces the surface 198, and the
surfaces 186 and 196 are ln abutting contact, and extend sub-
stantially parallel to each other. The locking band 202 is then
folded about the hinge portion 206 to cause the locking band to
be wrapped about the body portion 164, and the latchlng rlb 210
to be brought into a positlon of snap engagement wlth the rece3s
3S 178. When such snap en~agement ls effected, the conduit sectlon~
10 are located in end-end relation, ~nd are retalned flrmly ln
this position by the connector clamp.
'3
- 25 -
It will be noted i~ referring to Figure 14 that as the
lockin~ band 202 is folded about the body portion 164 and
positioned to facili~ate the snap engagement of the latching
rib 210 with the recess 178, the le~ 204 comes in contact with
the lockin~ plates 192, and causes these to be moved radiall~
inwardly through the slots 188 and 190 until the inner edaes
of the lockin~ plates, which are arcuate in configuration,
seat in and interlock with a pair of adjacent corru~ations
in the opposed conduit sections 10. Axial sliding movement
of the conduit sections 10 is thus prevented by this latching
engagement of the locking plates 192.
Another embodiment of inlet ~itting, also referred to as
a male terminal adapter, is illustrated in Figures 15 and 16.
The inlet fitting 208, as here illustrated, includes a medial
cylindrical body portion 210 which is characterized in having
a smooth outer peripheral wall and a smooth internal perlpheral
wall. The medlal cyllndrlcal body portlon 210 is formed
integrally, at one of its sides, with a pair of arcuately
cross-sectloned clamping portions designated generally ~y
reference numerals 214 and 216. The clamping portlons 214 and
216 extend in an axial direction from the cylindrical body
portion 10 and are identical in configuration to each other.
Each of the clamping portions 214 and 21S thus includes a
hinge portion 218 by which it is hingedly connected to the body
portlon 210. The hin~e portion is exteriorly defined by a
radially lnwardly projecting groo~e 220 formed transversely
across the clamping portion to reduce the thickness of the
synthetic resln material at this locatlon and permit flexin~ of
the clamping portion and pivoting movement inwardly and out-
wardly with respect to the axis of the lnlet flttlng.
A ramp or beveled or incll~ed surface 222 extends radially
outwardly from each clamping portlon from a point adjacent the
groove 220 to a point adjacent a rectangularly cros~-sectioned
recess or rellef 224. At the intersect~on of the ramp 222 and
the recess 224, a ~houlder 22~ is ~ormed; On the radlally
lnner side of e~ch of the clamping portions, ~ plurallty of
radlally inwardly projectin~, axially ~paced teeth 228 Ar~
~23~3
- 26 --
formed. It ~ill be note~ that the longest of these teeth which
projects the greatest radial distance into the interior of the
inlet fitting is located adjacent the axial end of the respec-
tive clamping portion which is spaced most distally rom the
cylindrical body portion 210, and that the length of the teeth
then diminishes in an axial direction toward the body portion
so that that tooth located nearest the shoulder 226 is the
shortest of the teeth and projects the shortest radial distance
into the fitting.
Slidably mounted around the body portion 210 for sliding
movement from that location into a position within ~he recess
224 (as illustrated in Figures 15 and 16) is an annular locking
collar 230. The locking collar 230 includes a rib 232 which is
positioned medially on the radially inner side of the locking
collar, and is located between two bevels or inclined surfaces
provided on the radiallv inner side of the lockins collar.
This construction permits the locking collar 230 to easily slide
upwardly over the ramp 222 from the medial cylindrical body
portion 210 and into the recess 224.
: 20 It will be noted in referring to Figures 15 and 16 that
the clamping portions 214 and 216 are each disposed on opposite
sides of the inlet fitting 208 illustrated in these figures so
as to be spaced from each other bv 180 around the inlet fitting,
and that the two clamping portions are separated from each other
by a pair of semi-cylindrical side portions 236 and 238. The
semi-cylindrical side portions 236~and 238 are formed on segments
of circles (in cross-section), and thus define with the clamping
portlons 214 and 216, a hollow cylindrical body which is adapted
to receive an end of one of the corrugated conduit sections 10
herelnbefore descrlbed~
On the opposlte side of the cylindrical body portion 210
from the side to wh1ch the side portion.~ 236 and 238 and clamplng
portions 214 and 216 are attached is a necked down portion of the
fitting 208 which defines a radlally lnwardly extendlng, annular
shoulder 240. The ~houlder 240 ls joined at lt~ inner ~lde to an
axially projecting, externally ~hr~aded nlpple 242. The out~ld~
diameter of the external threads 244 ~ormed on the nipplo 242 1
. .
~_ " .
g~3
- 27 -
such that the nlpple may be passed through the openina 246
formed in one of the side walls 248 of an electrlcal box. The
radially inwardly extending shoulder 240 forms a stop or abut-
ment preventing the remaining portion of the inlet fitting 208
S from passing through the openin~ 246.
When the inlet fitting 208 is mounted ~ithin the opening
246 in the side wall of an electrical box, the externally
threaded nipple 242 is passed through the opening 246 until
the shoulder 240 abuts the O-ring 250. At this time, a
threaded locking bushing 252, shown in dashed lines in ~igure
16, is threaded on the nipple 242 to firmly lock the inlet
fitting within the opening 246 of the box 248.
With ~he inlet fitting 208 locked in position in the
opening 246 in the box 24~ by means of the bushlna 252, the
lS clamping portlons 214 and 216 are permitted to flare out to a
locatlon which is diveraent with respect to the axis of the
inlet fitting. At thls time, the locking band 230 has been
slid alonq the fitting to a position where it surrounds the
medlal cyllndrical body portion 210. The end portion of a
corrugated conduit section 10 is then inserted into the open
end of the fitting between the side portions 236 and 238.
The lengths of the teeth 228 formed on the internal surface of
each of the clamping portions 214 and 216 and projecting
radially inwardly therefrom are dimensioned so that at this
time the teeth closes~ to the pivotal axis of each of the
clamping portions, thouah positio~ed closest to the axls of
the lnlet fitting, are shortest in length and thus do not
lnterfere wlth the insertion of the end portion of the corru-
gated sectlon 10 into the opened fitting.
After the conduit section has been firmly seated, in most
instanceS against the radially inwardly extending shoulder 240,
the locking collar or band 230 is slid axially alon~ the inlet
fittlng 208 until 1~ rides up over the ramps 222 on the outer
surface of each of the clamping portion~ 214 and 216 ~nd thu~
biases these clamping portions lnwardly about the hlnge portion
218 of each. Finally, the loc~lng coll~r or ba~d 230 is ~l~pp~d
into the recesses 224~so as to lock the cl~mpinq port~on~ 214
~3~)3
- 28 -
.
and 216 firmly in position where they are in allgnment and
complete a cylindrical fi~ure with the side portions 236 and
238. At this time, the teeth 228 firmly engage the corruga-
tions in the corru~ated conduit section 10 which has been
S inserted in the fittin~ to lock it in posltion and prevent it
from bein~ released from the fitting.
Although certain preferred embodiments of the invention
have been herein described in order to illustrate the principles
of the invention, it will be understood that various chanqes
10 and innovations can be made in the illustrated and described
structure without departure from ~he basic principles of the
invention. For example, in using the several system fittings
herein described, it may, in some installations and applications,
be desirable to use solvent bonding to join sections of conduit
lS to each other in end-to-end relation, or to join the end portion
of one or more conduit sections to or through a particular
fittin~. Thls technique is ~enerally well understood ln the
art, and where lt mlqht be used ln the system of the lnventlon
does not, per se, constltuta a novel aspect thereof. Changes
2Q and innovatlons whieh continue to rely upon and lnc.lude one or
more of the novel features of the system of the lntentlon are
thus contemplated, and such modifled systems are therefore
deemed to be circumscribed by the spirit and scope of the
invention except as the same is necessarily limited by the
appended claims or reasonable equivalents thereof.
