Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROIJND OF TEIE INVENTION
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The present invention relates to improvements in instant
fittings for reinforced, multilayer flexible tubings for fluids.
SUMM~RY OF THE PRIOR ART
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The fittings according to the present invention are
adapted to be used with flexible pipes of the type reinforced by
a braided sheath and comprising at least three layers, viz. an
inner tube, a braided sheath and a protective wearing layer.
The purpose of these fittings is to effect the virtually
instantaneous connection of this type of tubing, with a view to
making considerable savings in manpower and to enable such fittings
to be made by personnel having no special qualification therefor.
The connection of a reinforced multilayer flexible tubing
is presently complicated and often requires bulky equipment,
particularly for crimping and in any case the operation is always
long, fairly delicate and expensive, and requires specialised and
experienced manpower.
Fixing devices are known using a screw, in which the inner
part of the tubing is mounted on a bush and the outer layer is
strongly compressed under the effect of a tightening due to one
of the following effects:
- Effect of radial compression, by crimping, by collar,
shells or compressed split rings;
- Effect of compression obtained by annular rolling of
axial type with formation of a retaining bead;
- Effect of radial compression made by the extension by
forcing of the inner diameter of the tubing under the effect of
screwing the inner bush;
- Effect of axial annular compression on local swell of
the tubing due to a reinforcement of the central bush, by screwing
or unscrewing a nut.
It is also known to use devices for direct crimping
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on the outer wall of the body or indirect crimping of members
which are integral with the body.
Devices are also ~nown in which addi-tional members such
as annular rings, incorporated with the locking and screwing
members enable the screw tightening members to be rotated withou-t
the members holding the flexible being able to rotate at the same
time.
In certain known devices, the bush supporting the inner
wall of the flexible is separated from the body, is detachable,
possibly ro-tatable and sometimes comprises an annular seal between
said bush and the body of the fitting.
It is also known to use devices allowing the instant fit-
ting of a tubing simply by coupling said latter in the fitting.
These are generally fittings with self-locking means in which a
cone cooperates with annular parts self-locking on said cone,
constituted by clips or split rings and having teeth for catching
on the inner diameter, internally -fluted or threaded segments
or retaining rings or balls.
Other self-locking devices with radial tightening are
also known. However, almost all these self-locking devices with
instant fitting are provided for a homogeneous tubing of precise
or calibrated dimensions and are not suitable for a multilayer
flexible tubing.
In fact, the instant fittings are generally subjected to
the pressure at the end of the tubing and their seal is obtained
on the outer diameter of the tubing. Therefore, they cannot be
suitable for a reinforced multilayer flexible tubing which always
requires that the seal be made on the innex diameter and never
on the end of the tubing. In fact, if the pressurised fluid arrives
at the end of a multilayer flexible tubing, said fluid flows
along the wires of the reinforcing braided sheath which is
never perfectly embedded and incorporated in the layers
o plastomer or elastomer, and causes the outer wearing layer of
low resistance to burst at low pressure, rendering the tubing
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unaesthetic, dangerous and inaccep-table to the user.
~ mong instant fittings, two devices are known for which
the seal is made on the inner diameter of the tubing and which
would consequently be suitable for multilayer flexible tubings;
however, in reality, these two devices have been studied to re-
place and compete against the instant fittings mentioned above.
They are therefore made for assembly on a semi-rigid,
semi-supple or supple tube of fairly good calibration and are not
suited for multilayer flexible tubings. In particular, the parts
supporting the tightening ef~o~ are~not sufficient to withstand
the considerable forces transmitted by the pressurised fluld and
the forces of traction.
It is an object of the present invention to remedy the
above-mentioned drawbacks by providing an improved fitting intended
for reinorced multilayer flexible tubings.
SUMMARY OF THE INVENTION
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In accordance with the present invention, the fitting
comprises a body internally provided with a cylindrical inlet whose
diameter is substantially equal to that of the tubing, means for
~0 compressing the tubing within the fitting adjacent the cylindrical
inlet, said compressing means being followed by a generally conical
portion, increasing in diameter from the compressing means into the
fitting, said body having a bore adjacent the large diameter end
of the conical portion and corresponding in diameter thereto, said
conical portion internally receiving a rotatable bush with external
gripping teeth on which an end of the tubing can be engaged, said
bush having a cylindrical extension engaged in a bore of the body,
said bush having an external groove in which an annular seal is
disposed, said bush being axially movable to a position locked
aga.inst rotation when the tubing is pushed into the fitting,and the
tubing being gripped between the rotatable toothed bush and the
conical portion of the body when the tubing and fitting are under
tension.
The fitting according to the invention enables long,
meticulous and expensive assembly operations requiring specialised
manpower, to be avoided.
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According to a novel feature of the invention, the fitting
allows a virtually instant fi~ting of the multilayer flexible
tubings.
Furthermore, the considerable importance of flexibles for
fluids under pressure and the increasing part played by servo-
controls by means of fluids is realised in industry, this resulting
in any improvement in the costs of establishing the fittings of
multilayer flexibles rendering the use thereof easier and more
current.
The device according to the invention comprises an assembly
of members constituting the fitting ready for use and it has an axial
cylindrical bore substantially equal to the outer diameter of the
flexible tubing.
According to a feature of the invention, a bare flexible
tubing is used, without any preparation other than its cut to
length, to the exclusion of any other preparation such as removal
of the braid, etc
Fitting consists simply in forcibly pushing the previously
lubricated tubing withrecip ~cating and rotating movements (thrust
20 with alternate sectorial rotations of 90 to 180) to the end of
the fitting. Locking in permanent position of functioning is then
effected, either by pulling on the tubing (thus enabling its
correct holding to be checked) or by placing it under a sufficient
pressure for this locking to be effected automatically.
The fitting presents a self-holding of the tublng and a
permanent self-seal due to the pressure itself, and preventing any
leakage by creeping or loss of tightening of the tubing in time or
as a function of the influences of hot or cold thermal cycles.
The fitting made according to the inventlon ensures the rota-
tion of the tubing in the fitting, thus avoiding the kinking thereof
and enabling the fitting and its tubing to be unscrewed or re-
screwed on any apparatus.
The device according to the invention may be made either in the
form of independent fittings, or in the form of a complete accessory
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screwing on the majority of standard fittings available on the
market, (with cuttlng ring, compression, collet, flat face, etc...)
and tranforming said fittings into instant connecting members for
multilayer flexible tubing or in the form oE an inexpensive,
standardised, cylindrical part forming a cartridge, said part being
able to be fitted by crimping or screwed and crimped or simply
screwed in a very simple, inexpensive body or directly screwed in
an apparatus, either in the form of a fitting terminated by a
tubular part of internal dimensions equal to those of the tubing
and entering directly in one of the conventional known fittings,
or in the form of a fitting terminating in a part having forms
complementary of a known instant fitting~
The device according to the invention employs a method o
checking the correct assembly of the tubing. Different marks
printed on the tubing itself allow said tubing to be cut at the
suitable spot and the correct length of fit thereof in the fitting
to be checked as well as the locking stroke, in order to check the
assembly without any loss of time.
Two symmetrical markings are made on the tubing~ one on one
side for the fit at one of the ends of the tubing and the other on
the opposite side for the fit at the other end.
The tubing undergoes reversed stresses of tightening and
extension, offset axially during the assembly of the tubing, but
these stresses are then combined at one spot by axial displacement
of the tubing and the bush to the outside of the tubing up to a
permanent position of locking. The axial displacement effects at
first a proyressive annular radial compression, with wedge effect,
of the tubing between the bush and the rotary ring; after a
calculated axial stroke, there is then produced a permanent locking
due to the limit of compressibility of the tubing and also if need
be by means of catching teeth on a ring locking the tubing after a
predetermined axial stroke and compression of the tubing. The
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compression and locking of the tubing are maintained under con-
straint by the pressurised fluid which permanently pushes the
bush.
BRIEF DESCF~IPTIt)N OF THE DRAWINGS
Fig. 1 ls a view in longitudinal section of an embodiment
of an im~roved fitting according to the invention, in which the
upper half view represents the fitting during assembly of the
tubing and the lower half view in locked position;
Fig, 2 is a view in longitudinal section of anothex embodi-
ment of the fitting shown in Fig~ l;
Fig. 3 is a half-view in longitudinal section of another
embodiment of the fitting in position of assembly of the tubing;
Fig. 4 is a half-view in section of another embodiment in
locked position of the tubing;
Fig. 5 is a view in longitudinal section of a fitting screwed
on a support member;
Fig. 6 is a half-view in longitudinal section of another
embodiment of a fitting when the tubing is assembled;
Fig, 7 is a half~view in longitudinal section of another
embodiment of a fitting in locked position;
Fig. 8 is a half-view in longitudinal section of another
embodiment of a fitting made of sheet metal in fitted position of
the tubing;
Fig. 9 is a half-view of another embodiment of the fitting
with a body in one piece and in locked position;
Fig, 10 is a view of the marking on one of the faces of the
tubing;
Fig. 11 is a view of the presentation of the tubing for
assembly in the fitting;
Fig, 12 is a view of the fit of the tubing in the fitting;
Fig, 13 is a view of the tubing locked in the fitting;
Fig, 14 is a half-view in longitudinal section of an embodi-
ment of a fitting in assembled position;
Fig. 15 is a half-view in section of the same fitting as
Fig. 14 in locked position;
Fig, 16 is a half-view in section of another embodiment of
the fitting in assembled position;
Fig. 17 is a view in section of the same fitting as Fig. 16
in locked position.
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DESCRIPTION OF THE PREFERRED EMBODIMENTS
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Referring now to the d~awings, ~ig. 1 shows a fitting which
comprises a body 1 having a threaded part 23 on which is
screwed a nut 7 which is in abutment against a shoulder ld of
the body in order to constitute a housing having an inlet bore
7c for a multilayer flexible tubing ~ constituted by at least
three layers, viz. a plastics tube 8c, a braided sheath 8b and a
wearing layer 8a. A~ter the bore 7c there is provided a
cylindrical housing 7a in which is mounted, in free rotation,
a ring 6 which is axially held prisoner between the shoulder ld
of the body and a shoulder 7b of the nut.
The rotary ring 6 presents, near the bore 7c, a gripping
ridge 6b extending radially inwardly, followed by a generally
conical part 6a. A ter the ring 6, the body has a bore 22 of
diameter equal to the large diameter of the cone 6a and a tapped
part lc in which is screwed a ring 4 crimped at lh and presenting
a housing 4a in the form of a hollow hexagon. ~he ring 4 pre-
sents a shoulder against which abuts an O-ring 3 which is held
on the opposite side by a ring 2 subjected to the action of a
spring r in abutment against the end of a bore lb provided in
the body. Inside the fitting thus defined, there is moun-ted
to slide and rotate a bush 5 having a tubular ~errule 5c guided
in a bore lf of the body, in the rings 2 and 4 and by the
O-ring 3 forming seal and cooperating with a shallow groove 5d,
said bush comprising in its median part a boss 5b in the form
of a hexagon adapted to engage in the hexagonal housing 4a
to ensure the locking of the bush 5 in rotatlon.
At the end opposite the tubular ferrule, the bush 5
has a toothed ferrule having at least two teeth 5a on which is
engaged the end of the tubing 8. The bush 5 is immobilised in
translation by the annular O-ring 3 engaged in the groove 5d
of the bush and in rotation by the hexagonal boss 5b adapted to
be engaged in the corresponding housing 4a of the ring 4.
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The fitting according to the invention is used as follows:
The user having lubricated the end of ~he tubing 8 on the
inside and outside, introduces said tubing into the bore 7c ~top
half-view of Fig. l) and pushes it against the gripping ridge 6b
of the ring 6 so that the tube is compressed slightly to occupy the
position 8d and then it takes its normal diameter again to be
engaged on the toothed ferrule of the bush 5 and surmount the
gripping teeth 5a where it remains seized until the tubing 8 abuts
at the end of the fitting on boss 5b of the bush. The fitting on
the bush is obtained by alternately pushing and turning the tubing
through 90 and 180. During fitting, the bush 5 is immobilised
in rotation and in translation due to the engagement of the hex-
agonal boss 5b in the corresponding housing 4a integral with the
body.
The fitting is then locked, thls being obtained by pulling
on the tubing either manually or by a sufficient pressure of fluid
axerted on the socket 5 which acts as a piston with the 0-ring 3.
This results in an axial displac~ment of the bush 5 which comes
into the position shown in the bottom half-view of Fig 1.
The swollen part 8e of the tubing progressively bears on
the cone 6a of the ring 6 and the tubing undergoes a gradually
stronger radial, annular compression with wedge effect, since it is
gripped between the bush 5 and the rotary ring 6.
When the limit of compressibility of the tubing is reached,
the axial stroke stops in a position shown in the bottom half-view
of Fig. 1.
The pressurised fluid acting on the bush 5 and the 0-ring
3, maintains a permanent axial thrust on the zone of seal of the
channels, this allowing a constant tightness in time whatever the
thermal cycles ~within the limits authorised by the seal and the
tubing). Ageing and hot creeping are therefore not to be feared
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The assembly constituted by the tubing 8, the bush 5 and -the
ring 6, may rotate, when the ~ittiny is locked with or without
pressure and this avoids any kinking of the tubing on assembly,
and enables the fitting to ~e unscrewed from an apparatus, without
dismantling the tubing, and re-assembly. In fact, the bush 5
being disengaged from the hexagonal housing 4a, it is no longer
immobilised in rotation and the above-mentioned assembly may be
animated by a rotary movement.
As shown in Fig. 1, the spring r, by pushing the ring 2 on
the O-ring 3, efEects a permanent compensation of the seal of the
O-ring. This arrangement is very useful when the extreme varia-
tions in temperature are considerable.
The annular seal 3 may present different forms apart from the
O-ring shown and it may be constituted in particular by a lipped
seal or anti-extrusion washers which can resist high pressures.
Fig. 2 shows a simplified version of the fitting which does
not comprise any elastic compensation by means of a spring on seal
3. The seal 3 is mounted in a groove la machined in the body. The
hexagonal housing 4a in which the boss 5b of the bush may engage
for immobilising the bush 5, is made directly in the body 1.
The fitting shown in its fitted position in Fia. 3 is con-
stituted by an inexpensive, standardised body or cartridge 19, of
cylindrical external form, fitted in a bore of a ferrule l whose
edge lu is crimped to occupy the position lt in a groove l9b of
the body 19. This body or cartridge 19 may also be screwed and
crimped or simply screwed on a ferrule l or an apparatus.
A seal 21 may be mounted between the body 19 and the ferrule
l constituted by an O-ring or a sealed bonding.
Furthermore the rotary ring 9 is made with a flange 9c which
is engaged in a groove l9a of the body l9 and it is provided with a
~lot extending over half of its length, in order to render it
elastic and thus to allow it to be forcibly fitted by elasticity
in body l9. This assembly of the rotary ring 9 renders it ir-
removable and allows it to rotate.
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Fig. 4 shows, in locked position, a fitting which comprises
a monobloc body 1 in which is mo~mted a non-split rotary ring 9,
which presents a groove 9c located opposite another groove ls of
the body 1 so as to form a toric housing in which is engaged an
elastic retaining ring 18 ensuring the axial locking of the ring
9 but nonetheless allowing rotation thereof.
Fig. 5 is a variant embodiment of -the fitting of Fig. 2 which
constitutes a complete accessory adapted to be screwed on different
known types of fittings to transform them into instant fittings for
multilayer tubings.
To this end, a sufficiently long nut 7 is used, screwed on a
threading 18 of a body 1 of fitting of known type, said nut 7 in-
ternally receiving a screwed sleeve 10 which presents a bore lOb
and a hexagonal housing lOd identical to the housing 4a of Figs. 1
and 2 and of which the shapes in contact with the fitting 1 are
complementary thereof The top half-view of Fig. 5 shows a conical
fitting lOa with cutting ring or conical bush. The bottom half-
view of Fig. 5 shows a so-called compression fitting with its
radius 11 and its guide lk.
The assembly of parts 10 or 11 of the bush 5 of the seal 3 or
lla of the rotary ring 6 and the nut 7 -forms a complete accessory
which may be used without modification.
This assembly may be mounted on cutting ring, compression,
collet or flat face fittings.
The rotary ring 6 comprises a gripping ridge 6b and a conical
part as described hereinabove; however, there are provided on~ the
cone two catching teeth 6c and 6d on which the tubing catches and
is locked after determined axial stro~e and compression.
Of course, it is possible to provide one or more teeth on the
ring 6.
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Fig~ 6 shows a fitting in which the body 1 comprises a tapping
20 in which is engaged a hollow screw 12 which replaces the nut 7
and the rotary ring 6.
In order that the tubing in locked position may rotate in
working position, the cone 12a and the gripping ridge 12b are
subjected to an anti-adherent surface treatment which replaces the
rotary ring 6.
To avoid the bush 5 escaping with the tubing, by an excess
of sliding, a flange 5e is provided on the bush 5, so that said
flange 5e comes into abutment on the screw 12.
Fig. 7 shows a variant embodiment of the fi~.ting of Fig. 6,
in locked position, in which the flange 5e is replaced by a washer
13 ~buttin~ on the boss 5b oE the bush.
The monobloc body 1 receives a rotary ring 15 held by a
washer 14 on which a crimped edge lm of the body 1 is bent.
Fig. 8 shows another embodiment of a fittlng in locked posi-
tion which comprises a tubular end ls adapted to be fixed in the
majority of the known fittings (with cutting ring, compression,
etc..... ......)
The body 1 has a tapping 20 in which are screwed a ring 16
having a hexagonal housing 16a adapted to receive the boss 5b of
the bush 5 and a piece 17 made from stamped sheet metal. Inside
the piece 17 is mounted a rotary piece 17c made of thin sheet
metal, guided in the cone 17b and in abutment against the gripping
ridge 17a.
Fig. 9 shows another embodiment of a fitting in locked posi-
tion whi.ch comprises a monoblock body 1 internally provided with
the. diferent bores and housings shown in Fig. 2 which may be made
either by turning and boring directly with an outer from l_ and
an inner from 1~, or by cutting-off, reserving a thin tubular part
ln adapted to be shaped to present the final form lq and lr.
~ t the other end of the body 1, the general shape is cylindri~
cal with a groove lt. This shape is adapted for a direct assembly
in instant fittings of the female type.
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Fiys 10, 11, 12, 13 show a method of verifying that the
tubing has been correctly fitted in the fitting, said method en-
abling the depth of fit and the locking to be checked.
Fig. 10 shows a tubing 8 on which are printed several series
of marking signs, a first series of arrows 8f indicating the direc-
tion of fit of the tubing in the fitting; a second series of
transverse lines 8d regularly spaced apart by a distance ~ which
corresponds to the length to be fitted, and a third series of square
marks 8e spaced by a distance B from the lines 8d and which gives
the stroke of locking.
The same marking is made on the opposite side on the tubing
but in the reverse direction for assembling the other end.
When the tubing is to be fitted, it is firstly cut along line
8d as shown in Fig. 10 to separate the unwanted part 8g.
The tubing being internally and externally lubricated, it is
fitted as described previously until the line 8d (Fig. 12) is
flush with the fitting, so that the fitting is correct and checked.
1Ocking is then effected by pulling on the tubing 8 until the
square mark 8e is flush with the fitting 7 as shown in Fig. 13.
This method thus makes it possible to check whether the locked
position is correct.
If there is a doubt concerning the assembly, the cycle may be
started again by pushing the tubing to check the fit and pulling it
to verify the locking thereof.
If the pressure of the fluid is sufficient, locking is effec-
ted automatically ~der the pressure of the fluid; it is then
sufficient to check the appearance of the square mark 8e whose
stroke B in minimum.
If the tubings do not or could not comprise any marking, it
is posslble to provide on the outside of the fitting a mark 24
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for checking the fit of the tubing and a mark 25 for checking the
locking. The user having a non-marked tubing makes the marks on
the tubing himself by means of a marking member and using marks
24 and 25 which figure on the fitting to determine the dis-tance
A for fit and distance B for lockin~.
The present invention finds its applications for all
multilayer flexible tubings having a sufficient possibility
of "tightening" and "extension" for their differences in
diameter to be fairly large to permit the automatic manual
assembly without excessive efforts.
This type of fitting is used for automobile
braking tubing, braided PVC tubings, much used on machines
or water, lubricating liquids or coolants (oils, soapsuds,
emulsion), used also for sprinkling, for dispensing liquid
foodstuff, for compressed air, agricultural treatment and
hydraulic servo-control.
However, this fitting ~evice is used with multi-
layer flexible tubings having a sufficient possibility of
tightening and extension for the differences in diameters
obtained to allow locking.
However, it has been ascertained that this fitting
may be used with tubings of greater rigidity, particularly
multi-layer high pressure tubings in which there is little
possibility of extension and tightening.
The following embodiment has for its object an
improvement in the fitting, enabling tubings of greater
rigidity to be used.
The fitting shown in Figs. 14 and 15 comprises, as
in the preceding embodiment, a body l on which is screwed a
nut 7 having a cylindrical housing 7a in which is mounted
,
a rotary ring 6 which is axially held prisoner between a shoulder
7b of the body and an elastic ring or clip 27 engaged in a groove
6c in the rotary ring.
The rotary ring 6 has an inlet bore 6e of a flexible
multi-layer tubing 8, a bead 6b forming constriction, extending
radially to the outside, followed by a generally conical portion
6a,
Furthermore, the bod~ 1 presents a housing 30 in the
form of a hexagon followed by a tapped hole lc in which i5 screwed
a ring 4 against which abuts an anti-extrusion washer 2 and an
0-ring 3 disposed in the housing la of -the body 1.
Inside the fitting thus defined is slidably and rotatably
mounted a bush 5 having a tubular ferrule 5c guided over its
whole len~th in a bore le of the body, b~ the 0-ring 3, the washer
2 and the ring 4, said bush comprising in its median part a boss
5b in the form of a hexagon adapted to engage in the hexagonal
housing 30 to ensure locking o~ the bush 5.
At the end opposite the tubular ferrule, the bush 5
presents a toothed ferrule having teeth 5a and a channel or tooth
5g of larger diameter than teeth 5a on which the end of the pipe
8 is engaged.
Following the tooth or channel 5X there is provided a
groove 5e in which is mounted an 0-ring 28 in contact with the
inner surface of the tubing 8. A rounded part 29 provided on
the bush 5 between the groove 5e and the boss 5b is adapted to
receive the end of the tubing 8 when said latter is tightened,
as shown in Fig. 15,
A split ring 26 is interposed between the conical
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portion 6e of the ring 6 and the outer surface of the
tubing 8, said ring being provided externally with a
conical portion 26a cooperating with the conical portion
6a and internally with a series of teeth 26b adapted to be
engaged in the outer wall of the tubing 8. The ring 26 has
at least two longitudinal slots such as 26f which give it
suitable elasticity for assembly on the tubing 8.
The ring 26 is adapted to come into abutment against
a shoulder 6d of the rotary ring 6.
The split ring 26 which allows the tubing 8 to be
assembled is driven during the period of locking of the
tubing by the tubing itself, along the conical portion 6a,
this tightening the ring 26 on the tubing by its teeth 26b,
so that the tubin~ is securely gripped between the teeth 5a
and the teeth 26b, This powerful tightening effort is
calculated as a function of the tubing, its thickness and its
actual capacity of compression. The longitudinal stroke of
the bush 5 and of the tubing 8, the angle of the conical
portion 6a are provided to obtain the effort and compression
necèssary for the tubings used.
The bush 5 presents a large outer diameter preventing
ejection thereof, and it may come into positive abutment
axially in the ring 9.
The assembly as shown in Figs. 14 and 15 is intended
to allow a permanent axial thrust on part 8f of the
tubing. Furthermore, this fitting may be used with tubings
allowing a slight extension along 8e of the tubing, due to
the presence of a tooth Sg of larger diameter than the teeth
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or channels 5a.
Figs. 16 and 17 show another embodiment of the
fitting in which the rotary ring 6 has been eliminated
and the conical,portion 7f is made directly in the nut 7,
so that the ring 26 is in contact, by its conical portion
26a, with the conical portion 7f.
As in the preceding embodiment, the split ring 26
tightens the tubing 8 by its teeth 26b and has slots 26f.
The fitting shown in Figs. 16 and 17 is used more
particularly for assembling a tubing 8 which has virtually
no possibility of extension.
The bush 5 comprises a flange 5f against which
abuts the end 26e of the ring ~6, the other end of which
is adapted to abut against the shoulder 7e of the nut 7.
As in the preceding embodiment, the tubing 8 is
manually mounted by force on the bush 5, whilst the boss , `~
5b is engaged in the housing 30 and locking is effected
by pulling on the tubing 8 which drives the bush 5 whose
flange Sf comes into abutment against the end 26e of
the ring 26 displacing said ring in the direction of the
conical portion 7f of the nut 7, so that the end of the
tubing 8 is held compressed between the bush 5 and the
ring 26. Locking stops when the split ring 26 comes into
abutment against the shoulder 7e.
In this case, the conical portion 7f and part
7h comprise an anti-adherent coating allowing easier
rotation and locking of the tubing.
As the bush 5 extends by its tubular ferrule 5c
in the bore le of the body, it is possible to push the
bush axially by said ferrule 5c in order to proceed with
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locking, This operation may be effected manually, by means
of a jack or a threaded part. In this case, locking is
energetic and complete, which may be highly advantageous for
the mass manufacture of high pressure flexible tubings.
Verification, checking and locking of manufactured
flexible tubings may be effected by drawing on a traction
machine.
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