Note: Descriptions are shown in the official language in which they were submitted.
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A QUICK COUPLER THAT UNCOUPLES IN TWO STAGES
The invention relates to a quick coupler that
uncouples in two stages enabling the pressure of a fluid
in the coupler to be released prior to complete
uncoupling, the coupler comprising a female part and a
male part, the female part having a closure valve at its
upstream end, which valve is open when the female and
male parts are coupled together and is closed while they
are being uncoupled, the male part having an outside
surface provided with a collar, and the female part
including a latch which is movable a.n a radial direction
and which includes a bore extending in the axial
direction of the female part and through which the male
part passes, said latch including on the surface of its
bore two retaining projections designed to co-operate
separately with the collar of the male part, which
projections are offset from each other in the axial
direction.
French patent FR-A-1 503 989 discloses a quick
coupler in which the latch includes two teeth for co-
operating with a collar formed on the outer surface of
the male part, said two teeth being disposed on either
side of the male part on the latch so as to disengage the
male part from the female part in two stages
corresponding to the latch being pushed in once and
released once. Nevertheless, the engagement of the male
part in the sealing ring of the female part is such that
the male part is not fully disengaged from the sealing
ring or from the axial guidance portion, respectively,
when it is in its intermediate position, thereby making
rapid disengagement of the residual pressure downstream
from the valve of the female part impossible, since that
could result in whipping if the latch is released too
quickly.
In order to mitigate that drawback, French patent
application FR-A-2 514 855 proposes a quick coupler in
which the latch includes three locking teeth, of which a
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first tooth and a second tooth are arranged in separate
manner in the axial direction of the coupler inside a
radial bore of the latch, thereby defining a certain
axial distance over which the male part can move, and
where said first and second teeth are arranged on the
same side of the radial opening in the latch relative to
the male part which is inserted through said radial hole
of the latch, and where the third tooth is arranged in a
position that is axially between the first and second
teeth and on the opposite side thereto in the radial hole
of the latch. In this way, a shoulder formed on the
outer surface of the male part is locked in its fully
coupled position by the first tooth, and a first
operation of pushing in the latch disengages this first
tooth from the shoulder on the male part while
simultaneously causing the third tooth to engage in the
axial passage of the shoulder in the male part during
extraction so as to enable the male part to move back-
wards over an axial distance corresponding to the axial
distance between the first and third teeth. Thereafter,
the latch is released so that it returns into its initial
position under drive from a spring, and the third tooth
disengages from the shoulder of the male part as a result
of this release, while simultaneously the second tooth
engages in the axial passage of the shoulder in the male
part in order to enable said male part to reverse again
through an axial distance corresponding to the difference
between the axial positions of the third and second teeth
which retain the male part in the third axial position
before said male part is finally disengaged by a second
operation of pushing in the latch, thereby disengaging
the second tooth from the shoulder of the male part and
enabling the male part to be fully extracted, after which
the latch is released and returns to its initial
position.
In this manner, the male part is disengaged from its
coupling with the female part by a sequence of two pushes
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on the latch, a first push making partial uncoupling
possible during which the portion of the fluid under
pressure that is to be found downstream from the valve
can escape from the coupler prior to the male and female
parts becoming fully uncoupled, thereby making it
possible to avoid whipping due to said residual pressure
on uncoupling, and in particular, in the event of the
male and female parts being disengaged during the period
before the valve has closed completely.
The object of the present invention is to provide a
quick coupler that uncouples in two stages, and in
particular a quick coupler that uncouples in two stages
enabling the pressure of a fluid in the coupler to be
released before complete uncoupling, while requiring a
latch to be activated and related once only, and enabling
the two parts to be maintained temporarily connected
together after the latch has been released, and enabling
the parts then either to be recoupled or else completely
disengaged relative to each other, not by acting a second
time on the latch as described in French patent
application FR-A-2 514 855, but merely by pushing the
male part against the female part, which is possible even
while holding the pipe connected to the male part in
order to give it a small axial jog.
This object is achieved by a coupler as described in
the preamble, which is characterized by the fact that
each of the two projections in the bore of the latch is
in the form of a half-collar with at least one of them
being formed by two conical surfaces that are essentially
sickle-shaped, with at least the upstream-facing one of
said surfaces being suitable for fitting closely over at
least 180° of the collar of the male part.
Advantageously, the upstream-facing surface of the
frustoconical second half-collar situated axially further
downstream in the latch is also suitable for fitting
closely over at least 180° of the collar of the male
part.
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The downstream facing surface of the frustoconical
half-collar situated axially further upstream in the
latch may surround the collar over less than 180°.
In an embodiment of the present invention, the latch
is displaced radially by hand.
In another embodiment of the present invention, the
latch is activated by the caroming surface of a bushing
which is moved axially by hand.
The female part may include a first sealing ring for
sealing the inside of the female part relative to the
outside when the valve is in an open position, and also
seals said valve when it is in its closed position.
The female part may include a second sealing ring
for sealing the coupling between the valve and the male
part.
The valve may comprise an empty cylinder including a
closed head portion and a cylindrical portion provided
with holes that can be closed by said first sealing ring
when the valve is closed, said cylindrical portion
including two portions of different diameters of an axial
bore in said cylindrical portion, forming between them a
shoulder and a circumferential groove which serves as a
seat for a second sealing ring, the larger diameter
portion receiving a front portion of the male part.
The female part may include a spring urging the
valve into its closed position.
The head portion of the valve may include a frusto-
conical surface which is suitable for fitting closely
against a frustoconical surface of the first sealing
ring.
The larger diameter portion of the cylindrical
portion of the valve may include a plurality of radial
bores downstream from the second sealing ring, making it
possible, when the valve is closed and when the end of
the male part is disengaged from the sealing ring of the
valve, to exhaust the residual fluid under pressure that
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is to be found downstream from the valve towards the
outside.
The female part may include, in a downstream
position relative to the valve, a radial bore receiving
5 the latch, said radial bore opening out to one side of
the female part via an opening that is large enough to
pass the latch, and may include, at the end opposite to
said radial bore of the female part, an opening of
smaller size in communication with the radial openings of
the larger diameter portion of the cylindrical portion of
the valve to enable the residual fluid downstream from
the valve to escape to the outside of the female part
prior to the male and female parts being fully uncoupled.
The coupler may include an opening formed in the
front portion of the female part, or any other opening
allowing the fluid downstream from the valve to be
decompressed.
The invention is described below in detail with
reference to the drawings, by way of example.
Figures 1 to 6 show a coupler constituting an
embodiment of the present invention in six different
positions
Thus, Figure 1 is a longitudinal section through the
coupler in its completely uncoupled position.
Figure 2 is a longitudinal section (Figure 2a) and a
cross-section (Figure 2b) through the latch of the
coupler in a partially coupled-together position.
Figure 3 is a longitudinal section (Figure 3a) and a
cross-section (Figure 3b) through the latch of the
coupler in a fully coupled-together position.
Figure 4 is a longitudinal section (Figure 4a) and a
cross-section (Figure 4b) through the latch of the
coupler in a partially uncoupled safety position after
pushing on the latch.
Figure 5 is a longitudinal section (Figure 5a) and a
cross-section (Figure 5b) through the latch of the
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coupler in a partially uncoupled safety position after
the latch has been released.
Figure 6 is a longitudinal section (Figure 6a) and a
cross-section (Figure 6b) through the latch of the
coupler in its position immediately before complete
uncoupling.
Figure 7 is a longitudinal section through a coupler
forming another embodiment of the present invention, in
its fully coupled-together position.
Figure 8 shows four examples of male parts having
collar profiles that are appropriate for the present
invention.
Returning now to Figure 1, there can be seen a
coupler of the present invention in a fully uncoupled
position, the left side of the figure showing the up-
stream side where there is a source of fluid under
pressure, and the right side of the figure showing the
downstream side towards which the fluid under pressure
flows after the coupler has been fully coupled together.
The female part includes a first bushing 3 referred
to as an "outer" bushing, which includes an inside thread
at its upstream end, and a second bushing 1 that includes
an outside thread on its downstream end that is screwed
into the inside thread of the outer bushing 3, thereby
forming a housing for a sealing ring 4 which projects in-
wards from the two bushings.
The inner bushing 1 includes a shoulder 15
constituting a seat for a spring 2.
Inside the outer bushing 3 and also partially inside
the inner bushing 1, there is a valve 5 that includes a
head portion 16 and a cylindrical portion 17 which is
closed at its upstream end by said head portion 16, said
valve 5 being disposed so as to be axially slidable
inside an axial opening through the outer bushing 3 whose
inside diameter is substantially equal to the outside
diameter of the cylindrical portion 17 of the valve 5 so
as to guide the valve 5 accurately as it moves axially
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inside the outer bushing 3 during the various steps
involved in coupling and uncoupling the male and female
parts.
At its upstream end, the cylindrical portion 17
includes radial openings 18, while the head portion 16 at
one end of the openings and the cylindrical portion at
the other end thereof respectively include a frusto-
conical surface 19 and an annular surface as formed by a
polygonal generator line 20 suitable for fitting closely
against or being compressed against one of two
corresponding surfaces of the sealing ring 4 when the
valve 5 is respectively in its open position or in its
closed position.
Figures 1, 2, 4, 5, and 6 show positions of the
coupler in which the valve 5 is closed, i.e. in which the
frustoconical surface 19 of the head element 16 engages
closely against the frustoconical surface of the sealing
ring 4 so as to seal hermetically the portion of the
female part which is located upstream from the valve 5.
Figure 3 shows the valve 5 in its open position in
which the "polygonal" surface 20 is in contact with the
sealing ring 4 so that the openings 18 are open, thereby
allowing a fluid under pressure to pass from the upstream
end of the female part to the inside of the valve 5 by
passing through the openings 18.
The cylindrical portion 17 of the valve 15 includes
an inside bore having two sections of different
diameters, with the intersection of these two portions
forming a shoulder followed by a circumferential groove
in which there is received a sealing ring 6 which is
designed to seal the inside of the valve 5 and the inside
of the male part 10 towards the bore of the outer bushing
3 when the male part 10 is fully coupled inside the
female part.
The outer bushing 3 includes a radial bore 21 of
diameter greater than the diameter of its axial bore, and
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said radial bore 21 houses a latch 7 that is cylindrical
in shape.
The latch 7 has a radial bore 22 that occupies a
position that is more or less coaxial with the axial bore
in the outer bushing 3, so as to allow or prevent the
male part 10 to pass through the radial bore 22 of the
latch 7.
The male part 10 includes an insertion end 24 having
an outside diameter substantially equal to the inside
diameter of the larger diameter portion of the
cylindrical portion 17 of the valve 5 so that said end 24
of the male part 10 can be inserted into the cylindrical
portion 17 of the valve until it comes into abutment
against the sealing ring 6.
Downstream from the insertion end 24 of the male
part 10, the male part includes a circumferential
shoulder or collar 14 which is represented in Figure 1 by
its projection that includes a downstream slope and an
upstream slope, the upstream slope being steeper than the
downstream slope.
As can be seen in the longitudinal section of Figure
1, the radial bore 22 of the latch 7, includes a
projection 11 in the form of a frustoconical half-collar,
said first half-collar 11 being situated adjacent to an
accessible end of the latch 7, and a projection 12 in the
form of a frustoconical half-collar, said second half-
collar 12 being situated diametrically opposite the first
half-collar 11 and being offset therefrom in an upstream
direction.
Each of these two half-collars 11 and 12 is formed
by a pair of surfaces that are sickle-shaped, i.e. each
of them is curved to form a crescent extending over about
180° of a circle as defined by a radial section of the
inside wall of the bore of the latch 7.
In Figure 1 which is a longitudinal section through
the coupler, it can be seen that each of the two half-
collars 11 and 12 is represented by a projection having
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an upstream slope and a downstream slope, the downstream
slope being steeper than the upstream slope, the down-
stream slope corresponding to the upstream slope of the
collar on the male part, and the upstream slope
corresponding to the downstream slope on the collar of
the male part.
The upstream facing sickle-shaped surfaces of each
of these two half-collars are suitable for fitting over
at least 180° of the collar of the male part.
A spring 9 presses against a shoulder 26 of the
radial bore 21 of the outer bushing 3 to urge the latch 7
into a rest position, as shown in Figure 1.
In this completely uncoupled position as shown in
Figure 1, the fluid circuit is empty, fluid under
pressure upstream being held back by the valve 5 which is
urged against the sealing ring 4 by the spring 2 and by
the pressure of the fluid, and the latch 7 under thrust
from the spring 9 is in its rest position.
The larger diameter portion of the cylindrical
portion 17 of the valve 5 includes a downstream sealing
ring 6 for sealing the radial openings 27 and making it
possible, in the closed position of the valve 5 as shown
in Figure 1, for communication to take place between the
inside of the cylindrical portion 17 and the radial bore
21 of the latch 7.
This radial bore 21 also includes an opening 28
close to the shoulder 26 which serves as a seat for the
spring 9, thereby enabling residual pressure of fluid
contained inside the cylindrical portion 17 of the valve
5 and inside the male part 10, and also in all of the
downstream ducts, to escape to the outside during the
stage of operation of the coupler that is shown in Figure
4.
In order to obtain the partially coupled-together
position as shown in Figure 2, the male part 10 is pushed
into the female part, thereby moving the latch 7 down-
CA 02205483 1997-OS-16
wards by engagement of the collar 14 of the male part
engaging the half-collar 11.
The spring 9 is compressed and the front end 24 of
the male part 10 seals against the sealing ring 6. The
5 valve 5 is still in sealed contact against its sealing
ring 4.
In this position which is shown by Figure 2, the
male part is retained in the female part since the half-
collar 11 surrounds at least 180° of the downstream face
10 of the collar of the male part while fitting closely
against the shape thereof. The position of the male part
relative to the latch is shown particularly clearly in
Figure 2b.
To reach the fully coupled position, as shown in
Figure 3, the male part 10 continues to be pushed into
the female part so that the head portion 16 of the valve
5 pushes back the spring 2, so that the "polygonal"
surface 20 is no longer in contact with the sealing ring
4, and so that the openings 18 are opening and allow
fluid to pass, whether under pressure or not, from the
upstream end of the female part to the inside of the
valve 5, by passing through the openings 18.
During this operation, the latch 7 moves upwards
under thrust from the spring 9 so as to return to its
initial rest position.
In this fully coupled-together position, the male
part 10 is held in the female part since the half-collar
12 surrounds the downstream side of the collar 14 of the
male portion over at least 180° while fitting closely
over the shape thereof. The position of the male part
relative to the latch is shown particularly clearly in
Figure 3b.
This locking in the coupled-together position is due
to the fact that the conical sickle-shaped surface of the
collar 14 cannot slide over an opposing surface having
the same shape as the surface of the half-collar 12 if it
extends over 180° or more of the sickle-shaped surface.
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No locking takes place in the coupling direction
because, as shown in Figure 1, the distance dl is less
than the distance d2, which means that in the coupling
direction, the half-collar 12 surrounds the collar 14 of
the male part over less than 180°, whereas in the
uncoupling direction, the half-collar 12 surrounds the
collar 14 of the male part over 180°, or more.
Sealing relative to the outside is provided by the
sealing ring 6 which bears against the front portion 24
of the male part 10, and by the shoulder 33 (Figure 3a)
of the valve 5 which presses against the sealing ring 4.
When it is desired to uncouple the male and female
parts, hand pressure is applied to the accessible end of
the latch 7 so that the latch moves downwards, thereby
disengaging the collar 14 from the half-collar 12, after
which the male part reverses in the disengagement
direction until it is retained via its collar 14 by the
half-collar 11 which is at a certain distance axially
downstream from the half-collar 12.
This pushing in of the latch 7 thus enables the male
part 10 to reverse under drive from the inside fluid
pressure until it reaches an axial position in which the
collar 14 comes into abutment against the half-collar 11.
In this way, the half-collar 11 surrounds the collar 14
over 180° at least thereof, and fits closely to the shape
thereof.
During this reversal, which terminates in a final
position referred to as a "partially uncoupled" position
as shown in Figure 4, the valve 5 is pushed into its
closed position by the spring 2 and by the upstream fluid
pressure, and the end of the male part 10 disengages both
from the sealing ring 6 and at least partially from the
radial openings 27 in the cylindrical portion 17 of the
valve 5 so as to allow fluid under pressure that is to be
found downstream from the valve 5 to escape through the
openings 27, the radial bore 21 in the latch 7, and
finally the opening 28 or 29 so as to eliminate any force
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due to fluid pressure situated downstream from the valve
5, subsequently allowing disengagement to continue until
the male part is fully disengaged by reversing the half-
collar 11 into its initial position corresponding to the
rest position of the latch without any danger of whipping
which would normally occur if the male part is allowed to
uncouple without restriction while the ducts downstream
from the valve 5 are still under pressure.
The bore 29 parallel to the axis is provided in the
front portion of the female part and acts as a second
exhaust path for the pressure.
Figure 5 shows the coupler in a partially uncoupled,
safety, position after pressure on the latch 7 has been
released. The half-collar 11 surrounds the collar 14 of
the male part over at least 180°, and on the downstream
side thereof, thus retaining the male part in the female
part. This retention is provided by the thrust due to
the pressure of the downstream circuit until the residual
pressure has been released, and subsequently merely by
friction between the two conical sickle-shaped surfaces
of the half-collar 11 and of the collar 14, respectively,
preventing the latch from returning to its rest position.
The male part 10 is thus locked in this position and the
latch 7 remains in its low position with the spring 9
compressed. In this position, the assembly remains in
unstable equilibrium and the male part 10 cannot be
withdrawn for the time being from the female part.
From this "partially uncoupled", safety position, it
is possible either to recouple the two parts of the
coupler by exerting axial thrust in the coupling
direction until they each the fully coupled position as
shown in Figure 3, or else to disengage the two parts
fully from each other.
To separate the male part from the female part, a
short-duration axial thrust is exerted in the coupling
direction to disengage the two respective sickle-shaped
surfaces of the half-collar 11 and of half of the collar
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14, thereby separating the half-collar 11 from the collar
14. Figure 6 shows the position immediately before full
uncoupling, in which the male part is pushed in a little
in the direction of arrow F. Full uncoupling is obtained
by axial thrust on the male part in the coupling
direction as shown by arrow F until the latch 7 is
released and has risen to its initial, rest position
under thrust from the spring 9. As a result, the half-
collar 11 moves away from the axial path of the collar 14
and the male part 10 can be withdrawn so that the coupler
is fully uncoupled, as shown in Figure 1.
Figure 7 which shows another embodiment of the
present invention, shows a coupler that is identical to
that of Figures 1 to 6, except that it includes a latch 7
which is actuated by the cam surface of a bushing and not
directly by the hand applying thrust to the latch as in
the embodiment of Figures 1 to 6. The reference numerals
are identical to those used in Figures 1 to 6.
The coupler shown in Figure 7 is in its fully
coupled position.
The latch 7 has a spherical portion 35 and is
surrounded by an outer bushing 30 that slides axially and
that includes a cam surface 34 for co-operating with the
spherical portion 35 of the latch to actuate the latch 7.
The bushing 30 bears against a spring clip 32 via a ring
31. The collar 14 of the male part 10 is surrounded over
at least 180° by the half-collar 12 of the latch 7 which
is in its rest position. The valve 5 is open.
To reach the safety, uncoupled position, the bushing
30 is moved axially in translation in the upstream
direction. The spherical portion 35 of the latch 7 is
camped by the ramp 34 on the bushing 30, thereby causing
the latch 7 to move perpendicularly to the longitudinal
axis of the male part 10 and of the female part 3. This
downwards movement enables the collar 14 to be disengaged
from the half-collar 12. At this moment, the male part
reverses under thrust from the spring 2 via the valve 5
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and the sealing ring 6. When the spherical portion 35 of
the latch 7 lies over the cylindrical portion 36 of the
bushing 30, the half-collar 11 of the latch 7 surrounds
the collar 14 of the male part over at least 180°,
thereby retaining it in the female part 1. In this
position, the valve 5 is again in abutment against its
sealing ring 14, thus holding back the upstream pressure.
The front portion 24 has left the sealing ring 6, thereby
connecting the pressure on the downstream end to the
atmosphere via the holes 28 and 29, and the orifices 27
through the valve 5. The bushing 30 in its rear position
holds the latch 7 in this position so the male part
cannot be disengaged. In its rear position, the bushing
reveals a colored ring 31 indicating that the coupler is
in its safety position.
To fully uncouple the coupler, the bushing 30 is
returned to its initial position by being moved in the
downstream direction. The spherical portion 35 of the
latch 7 thus leaves the cylindrical bore 36 and returns
to the housing 37 formed in the bushing 30. The latch 7
follows the ramp 34 under thrust from the spring 9. In
this way, the collar 14 disengages from the half-collar
11,, and the male part can be fully disengaged.
Around its periphery at its narrowest portion, the
bushing 30 may include radial holes which make it easier
to disengage the residual fluid escaping from the opening
28 during the intermediate stage of uncoupling.
Figure 8 shows four examples of male parts having
different collar profiles which are particularly well
adapted as male parts for use in the present invention.
The various collar profiles shown in Figures 8a to 8d are
profiles complying with the following standards: ISO 6150
A (Figure 8a); ISO 6150 B (US MIL C 4109) (Figure 8b);
ISO 6150 C (Figure Sc); and ARO 210 (Figure 8d).
Clearly, any collar profile could be used providing the
shape of the projections into the bore of the latch in
CA 02205483 1997-OS-16
the female part matches the shape of the collar of the
male part in accordance with the present invention.
The invention is described above with reference to
two possible embodiments, it being understood that
5 numerous modifications could be provided by the person
skilled in the art without going beyond the spirit of the
invention.
This spirit of the invention lies in the principle
whereby full uncoupling of a coupler is provided by
10 pushing on the latch once only and then releasing it,
enabling partial uncoupling to be obtained between the
male and female parts and enabling them to be maintained
in the safety, or partially uncoupled position, followed
by axial thrust on the male part in the coupling
15 direction that enables the male part to be fully
r. ..a r.._.. ... ~L _ _ L
ui~eWgctgCU. Luttttg Lil~ 5tdge 1I1 WIllch Zlle male part 1.s
partially disengaged in the female part, the pressure of
any fluid downstream from the valve can quickly escape,
with this taking place before the full disengagement
stage can be performed.
To enable the fluid under pressure downstream from
the valve in the female part to escape, it is necessary
to provide a reverse path for the male part while
pressing down the latch, so that the male part can move
from its fully coupled position to its partially
uncoupled position, thereby enabling both the valve to be
closed and the exhaust paths for said fluid to be opened.
