Note: Descriptions are shown in the official language in which they were submitted.
~5~
The present invention relates to couplings
in general, and more particularly to improvements in
couplings (hereinafter called hose couplings) which
can be used to establish separable but fluidtight
connections between pairs of tubular components,
especially between a rigid component and a deformable
component. Typical examples of such components are
nipples or analogous pieces of pipe (hereinafter
called pipes) and hoses consisting of flexible
10 material. Still more particularly, the invention
relates to improvements in hose couplings of -the
type wherein the means for securing the hose to the
pipe includes a tubular connector.
German Pat. No. 30 01 991 discloses a
hose coupling wherein a pawl is provided on a
connector to separably lock the connector to the
pipe. The pawl is biased to a locking position,
in which its pallet engages a radial shoulder of -the
pipe, by a torsion spring and the pivo-t for the
20 pawl is carried by a sleeve which surrounds the
connector and is movable axially thereon against the
opposition or under the action of a coil spring.
The purpose of the coil spring is to urge the sleeve
and the pawl thereon in a direction to maintain the
pallet of the pawl in engagement with the radial
shoulder of the pipe. The coil spring reacts against
an external shoulder of the connector and bears
against an internal shoulder of the sleeve. One
end of the connector has a frustoconical ex-ternal
30 surface which bears against an O-ring and urges the
~ ,~
~s~3~
latter agains-t an internal surface of the pipe
under the action of the coil spring.
A drawback of the patented coupling is
that it comprises an excessive number of component
parts including the aforementioned sleeve, a coil
spring and a discrete torsion spring for each pawl.
Moreover, several component parts of the patented
coupling are rather complicated so that their
manufacturing cost contributes significantly to the
overall cost of the coupling. E'urthermore, the
patent does not disclose the manner in which the
connector can be secured to the hose.
U.S. Pat. No. 3,394,954 discloses a tube
coupling for medical appliances wherein a -tubular
connector is assembled of several parts and serves
to establish a path for the flow of a fluid medium
between two rubber tubes. The patented coupling is
quite complex and the connections between the connector
and the rubber tubes are unreliable.
UOS. Pat. No. 4,123,091 discloses a tube
coupling with a positive locking connect and ready
disconnect. The coupling has several complex
parts and its dimensions, as considered in the
radial direction, are quite substantial.
Additional hose couplings are disclosed
in U.S. Pat. No. 1,043,683, in U.S. Pat. No. 1,312,584
and in British Pat. No. 1,334,486. These couplings
are not only bulky but also ex-tremely complex so
that they and/or their parts cannot be mass-
produced at a reasonable cost which is a prerequisite
for the utilization of hose couplings in motor
vehicles and the llke.
The invention resides in the provision of a
coupling which comprlses a pipe (e~g., a nipple which
is rigid with -the engine block in a motor vehicle)
having a first end portion, a hose having a second end
portion, a tubular connector having a first section
surrounded by the first end portion and a second section
in direct or indirect sealing engagement with and
arranged to share axial movements of the second end
portion, a sealing element (e.g., an O-ring or a
sleeve) which is interposed between the first section
and the first end portion to establish and maintain
a fluidtight seal between the connector and the pipe
while permitting at least some axial movement of the
first end portion and the first section relative to
each other, and at least one latching device which
serves to releasably lock the connector to the pipe.
The latching device includes a mobile(elastic or
rigid)firs-t portion which is a-t least indirectly
supported by the connector and a second portion (e.g.,
a pallet) which is movable into and from engagement with
the pipe, e.g., at least in part against the opposition
of the first portion (for example, the first portion of the
latching device can include a flexible web which yieldably
opposes movement of the second portion away of engagement
with -the pipe). The sealing elemen-t preferably
engages a cylindrical internal surface of the pipe,
and at least a portion of the connector preferably
~} --
~2~
constitutes a metallic or synthetic plastic cylinder.
The first portion of the latching device preferably
defines for the second portion a pivot axis which
is at least substantially tangential to the first
end portion so that the second portion of the
latching device is movable in a plane which includes
the axis of the first end portion. Instead of or in
addition to an elastically deformable web, the
first portion of the latching device can comprise or
constitute a spherical joint which secures the second
portion of the latching device to the connector.
The second portion of the latching device is preferably
accessible, most preferably freely accessible, at
the exterior of the first end portion so as to allow
for convenient detachment of the second portion of
the latching device from the pipe.
In accordance with one presently preferred
embodiment of the invention, the second section of
the connector is confined in the second end portion
and the first portion of the latching device
extends from the connector outwardly between the
first and second end portions. Also, the second
sec`ion of the connector can be mechanically
secured to the second end portion, e.g., by
providing the second section with one or more
external ribs and by employing a clamping device
which surrounds the second end portion and urges
its material against the rib or ribs of the second
section. It is preferred to employ a hose whose
(second) end portion consists of a deformable
-- 5 --
material, such as natural or synthetic rubber. The
latching device can be provided with an additional
portion which bears against the exterior of the
second end portion to urge the latter against the
rib or ribs oE the second sec-tion while the second
portion of the latching device engages the pipe.
The second and additional portions of the latching
device are preerably disposed at the opposite
sides of the first portion, as considered in the
axial dlrection of the two end portions, and the
additional portion of the latching device can slope
inwardly toward the axis of the second end portion
in a direction away from the first end portion. The
second section of the connector can be provided wi-th
one or more external grooves adjacent to -the rib or
ribs, and the additional section of the latching
device can be arranged to urge the material of the
second end portion into at least one such groove
when -the second portion of the latching device engages
the pipe, i.e., when the pipe is locked against
axial movement relative to the hose and connector.
The inner side of the second portion (e.g.,
the aforementioned pallet) of the latching device
can slope toward the axis of the first end portion
in a direction away from the second end portion.
This enables the second portion of the latching
device to slide over a radially extending shoulder
at -the free end of the first end portion in order -to
allow for disengagement of the pipe from the hose in
response to the application of an excessive axial
stress to the first and/or second end portion ln a
direction to move such end portions apart. The
second portion of the latching device can engage a
radial shoulder, a cylindrical portion or a
frustoconical portion of the external surface of the
first end portion.
The aforementioned additional portion of
the latching device can be designed to facilitate
disengagement of the second portion from the pipe.
To this end, the additional portion can slope
outwardly and away from the axis of the second end
portion in a direction away from the first end portion.
The second section of the connector can
be bonded, e.g., vulcanized, to the second end portion,
and such second section can be surrounded by or it
cansurround the second end portion. For example,
the second end portion can surround the second
section of the connector and can but need not
necessarily abut the first end portion. Alternatively,
the second end portion can be received between the
second section of the connector and the first end
portion, for example, in such a way that the second
end portion is surrounded by the first end portion
and surrounds the second section. It is also
possible to design the coupling in such a way that
one of the two end portions (particularly the first
end portion) surrounds the other end portion; this
contributes to the establishment of a highly
reliable fluidtight seal between the two end portions).
The sealing element can comprise at least
~5~
one circumferentially complete deformable sealing
lip which is in sealing contact with the preferably
cylindrical internal surface of the first end portion,
and such sealing lip can be in-tegral with the second
end portion (i.e., the seallng element can
constitute an integral part of the hose).
The second section and the second end
portion can be disposed end-to-end and their
abutting end faces can be bonded (e.g., vulcanized~
to each other. For example, the connector can
include a flange-like third section which is disposed
between the firs-t and second sections (or which can
constitute or form part of the second section) and
has one of the aforementioned end faces which are
bonded -to each other.
The sealing element can be received in an
external groove of -the first section of the
connector or it may be bonded (e.g., vulcanized) to
the connector. The second section of the connector
can surround a portion of the sealing element.
It is also possible to provide the first
end portion with an opening through which the latching
device extends radially outwardly or which receives
at least the major part of the latching device. The
latter is then preferably (but not necessarily)
integral with the connector.
The novel features which are considered as
characteristic of the invention are set for-th in
particular in the appended claims. The improved
hose coupling itself, however, both as to its
construction and its mode of operation, together
with additional features and advantages thereof,
will be best understood upon perusal of the
following detailed description of certain specific
embodiments with reference to the accompanying
drawing.
FIG. 1 is a fragmentary partly elevational
and partly axial sectional view of a coupling which
embodies one form of the invention and wherein the
end portion of the hose is mechanically secured to
the respective section of the connector by a band-
shaped clamping device;
FIG. 2 is a fragmentary partly elevational
and partly axial sectional view of a second coupling
with a modified latching devices which forms part
of the means for mechanically securing the end
portion of the hose to the respective section of the
connector;
FIG. 3 is a simi.lar view of a coupling
which constitutes a modifica-tion of the coupling
of FIG. 2 and whose latching devices are secured to
the connector by spherical joints;
FIG. 4 is a fragmentary axial sec-tional
view of a fourth coupling with a modified sealing
element and a connector which surrounds the end
portion of the hose;
FIG. 5 is a similar sectional view of a
coupling which constitu-tes a modification of the
coupling shown in FIG. 4;
FIG. 6 is a fragmentary axial sectional
view of a coupling wherein the latching element
or elements are not integral with a metallic
connector;
FIG. 7 is a similar sectional view of a
coupling which constitutes a modification of the
coupling shown in FIG. 6 and wherein the latching
device or devices are integral with the metallic
connector;
FIG. 8 illustrates a modiEication of the
coupling which is shown in FIG. 7;
FIG. 9 is an end elevational view of the
connector which forms part of the coupling shown
in FIG. 8;
FIG. 10 is a fragmentary axial sectional
view of a coupling constituting a modification of the
coupling which is shown in FIGS. 8 and 9;
FIG. 11 is a fragmentary axial sectional
view of a further coupling wherein the latching
device extends outwardly through an opening in the
end portion of the pipe;
FIG. 12 is a similar view of a Eirst
modification of the coupling which is shown in
FIG. ll;
FIG. 13 is a similar view of a second
modification of the coupling which is shown in FIG.
ll; and
FIG. 14 is a similar view of a third
modification of the coupling which is shown in
FIG. 11.
Referring first to FIG. l, there is shown
-- 10 --
,f~ t-~
a coupling which comprises a first tubular component
3 (hereinafter called pipe for short) which can
constitute a metallic nipple forming part of an
engine block in a motor vehicle, a second tubular
component 1 (hereinafter called hose) which can
consist of an elastomeric material (such as EPDM,
silicone rubber or another rubber-like substance),
a tubular connector 2 having a first section 4
surrounded by the end portion of the pipe 3 and a
second section 5 surrounded by the end portion of the
hose 1, and a sealing element 7 in the form of an
O-ring which is interposed between the cylindrical
internal surface 8 of the end portion of the pipe 3
and the external surface of the section 4. The
hose 1 need not necessarily consist of a pronouncedly
elastomeric material, i.e., its material can be
hard or substantially hard as long as the end
portion of the hose 1 can he properly slipped onto
the second section 5 of the connector 2. That
portion of the connector 2 which constitutes the
section 4 is a cylinder having a circumferentially
complete external groove 6 for the major portion of
the sealing element 7. The latter is inserted in
prestressed condition and ensures that the end
portion of the pipe 3 is and remains in sealing
engagement with the first section 4 even if the
connector 2 is shifted axially of the pipe 3 and/or
vice versa, as long as the sealing element 7
remains in con-tact with -the cylindrical internal
surface 8 of the end portion of the pipe 3. The
~5~
connector 2 is preferably made of a relatively
hard but at least slightly elastomeric synthetic
plastics material suc'n as polyamide which is
reinforced by glass fibers.
The external surface of the second
section 5 of the connector 2 is provided with a
first circumferentially complete rib 9 having a
frustoconical flank which slopes toward the axis
of the connector 2 in a direction away from the
secti.on 4 and a radial flank which faces toward the
pipe 3. The external surface of the section 5 is
further provided with a set of additional ribs 10
each of which has a substantially sawtoo-th shaped
profile and has a frustoconical flank sloping toward
the axis of the connector 2 in a direction toward
the section ~ as well as a radially extending flank
facing away from the pipe 3. The maximum diameters
of the additional ribs lO are preferably smaller than
the maximum diameter of the rib 9, and a-t least
some of the ribs lO are surrounded by a band-like
metallic or plastic clamp 11 which biases the
material of the end portion of the hose 1 into the
annular spaces between the ribs lO therewithin.
The mechanical connection between the second
section 5 of the connector 2 and the end portion
of the hose l is similar or analogous to that which
is disclosed in the commonly published German
patent application Serial No. 28 52 965 filed
December 1, 1978.
In accordance with a feature of the
- 12 -
invention, the improved coupling further comprises
at least one pawl-shaped latching device 13 which
is integrally secured to an intermediate portion of
the connector 2 by a web 12 forming part of or
constituting a first portion of the device 13.
The latter fur-ther comprises a pallet-shaped
second portion 14 which releasably engages -the pipe
3 to hold the connector 2 against axial movement
in a direction to the right, as viewed in FIG. 1,
and an additional or third portion 18 which can be
actuated by a finger 19 to disengage the pallet-
shaped second por-tion 14 from the pipe 3 so that
the latter can be disconnected from the section 4
against the opposition of the sealing elemen-t 7
which is in frictional and sealing engagement with
the in-ternal surface 8 and is confined in the
external groove 6 of the section 4. The web 12
is disposed between the end portions of the pipe 3
and hose 1 and is elastic. Thus, when the additional
or third portion 18 of the latching device 13 is
to be depressed toward the external surface of the
end portion of the hose 1, the flnger 19 must
overcome -the resistance of the web 12 in order -to
disengage -the por-tion or palle-t 1.4 from an external
radially extending shoulder 17 of a circumferentially
complete tooth-shaped portion or bead 16 of the
pipe 3. The bead 16 has a frustoconical surface 15
which tapers toward the axis of the pipe 3 in a
direction away from the radial shoulder 17. The
elas-ticity of -the web 12 is such tha-t the portion or
pallet 14 normally tends -to engage -the shoulder 17,
and the third or additional portion 18 of the latching
device 13 then slopes outwardly in a direction away
from the axis of the hose 1 and away from the end
portion of the pipe 3.
When the firs-t section 4 of the connector
2 is introduced into the end portion of -the pipe 3,
-the second portion or pallet 14 of the latching
device 13 rides over the frustoconical flank 15
of the bead 16 against the opposition of the
elastically deformable web 12 and thereupon snaps
behind the shoulder 17 to hold the connector 2
ayainst separation from the pipe 3. The bias of the
web 12 suffices to ensure that the second portion or
pallet 14 of the latching device 13 remains in
engagement with the radial shoulder 17 unless the
finger 19 of an operator depresses the third or
additional portion 18 so as to pivot the latching
device 13 in a plane including the axis of the
connector 2, i.e., about an axis which is defined
by the web 12 and extends substantially tangentially
of the end portion of the pipe 3.
The ability of the improved coupling to
resist separation of the first section 4 of the
connector 2 from the end portion of the pipe 3
can be enhanced by providing the connec-tor 2 with
two or more latching devices 13, e.g., with two
latching devices which are disposed diametrically
opposite each other with reference to the common
axis of the connector 2 and the end portions of
- 14 -
the pipe 3 and hose 1. If the connector 2 carries
two or more latching devices, such devices are
preferably of identical size and shape and are
preferably equidistant from one another, as
considered in the circumferential direction of the
coupling. The third or addi-tional portions 18 of
two or more latching devices 13 can be depressed
by one hand and at the same time to ensure a
convenient and rapld separation of the first section
4 from the end portion of the pipe 3 when the need
for such separation arises.
The web 12 may but need not necessarily
store energy when the pallet 14 engages the radially
extending shoulder 17 of the bead 16. However, the
web 12 preferably stores energy while the pallet
14 rides over the frustoconical flank 15 in a
direction toward the shoulder 17. This reduces the
likelihood of accidental separation of the latching
device 13 from the bead 16, i.e., it is necessary
to depress the third or additional portion 18 in
order to allow for separation of the first section
4 from the end por-tion of the pipe 3.
An important advantage of the improved
coup]ing is that it can dispense with -the spring-
biased sleeve which surrounds the tubular connector
of the coupling shown in the aforediscussed German
Pat. No. 30 01 991. Moreover, the improved
coupling dispenses with a ring-shaped retainer for
the sleeve which is used in the German patent as
well as with the coil spring and with the torsion
~5~
spring or springs of the patented coupling. Still
further, the internal surface of the pipe 3 need
not be provided with a frustoconical portion such
as that ln the pipe which is used in the coupling
of the German patent and is engaged by the sealing
element. The omi,ssion of the coil spring reduces
the effort which must be exerted in order to connect
the pipe 3 with or to disconnect the pipe from the
hose 1. Still further, the improved coupling can
be readi.ly manipulated by a robot in an automated
automobile assembling or other plant. The
mechanical connection between the connector section
5 and the end portion of the hose 1 by means of a
simple clamp 11 or the like can be established in the
manufacturing plant rather than at the locale of use
so that the attachment of the hose 1 to the pipe 3
takes up even less time since it merely involves
insertion of the connector section 4 into the
end portion of the pipe 3. The sealing element 7
is or can be inserted into the groove 6 at the locale
of assembling the connector section 5 with the end
portion of the hose 1.
The feature that the web 12 of the first
portion of the latching device 13 is integral with
! the connector 2 also contribu-tes to lower cost and
simplicity of the improved coupling. Thus, it is
not necessary to provide a discrete pintle or the
like for each latching device 13 and it is not
necessary to provide a discrete spring (such as the
torsion spring which is shown in the aforementioned
- 16 -
~5~
German patent) to bias the pallet 14 of the latching
device 13 into engagement with -the pipe 3O
An additional important advantage of -the
improved coupling is its simplicity. Thus, even an
unskilled person can immed.iately perceive -the purpose
and mode of manipulation of the readily observable
and readily accessible latching device or devices
13 so that the mode of operation of the improved
coupling need not be described in detail in expensive
manuals and the person in charge of assembling or
taking apart the improved coupling need not require
any training for proper manipulation of the latching
device or devices 13.
Still another important advantage of the
improved coupling is its compactness. Thus, the
coupling does not contribute to the combined axial
length of the pipe 3 and hose 1 since the end face
of the end portion of the hose 1 can be moved into
immediate or very close proxi.mity of the end face
of the end portion of the pipe 3. All that is
necessary is to leave an extremely narrow gap for
the passage of the web 12 radially outwardly so
that -the second and third por-tions 14 and 18 of the
latching device 13 can be located externally of
the end portions of the pipe 3 and hose 1.
Compactness of the coupling is highly desirable,
not only because it entails a reduction of the
initial cost for the material of -the parts 2 and 13
but also because the coupling occupies less room
under the hood of a motor vehicle if the improved
- 17 -
~5~
coupliny is used in connection with the assembly
of automobiles.
FIG. 2 shows a second coupling which
employs a modified tubular connec-tor 2a and a pipe
3a having a modified end portion surrounding the
respective section 4 of the connector 2a. The
section 5a extends into the end portion of the hose
1 and has a circumferentially complete external rib
9a as well as a circumferentially complete external
groove lOa inwardly adjacent to the rib 9a and
receiving a part of the end portion of the hose 1
under the action of a third or additional portion 20
of a modified latching device 13a. The manner in
which the sealing element 7 is received in the
external yroove 6 of the section 4 of the connector
2a and engages the cylindrical internal surface 8
of the end portion of the pipe 3a is the same as
described in connection with FIG. 1. The connector
2a is preferably made of a relatively stiff bu-t at
least slightly elastomeric material, such as
polyamide which is reinforced by glass fibers. The
first portion of the latching device 13a constitutes
a web 12 which is elastic and tends to maintain
the second portion or pallet 14a of the device 13a
in engagement wi-th the cylindrical portion 21 of the
external surface of the end portion of the pipe 3a.
The cylindrical portion 21 is inwardly adjacent to
a frustoconical surface or flank 17a which slopes
toward the axis of the end portion of the plpe 3a
in a direc-tion away from the hose 1. The circumferentially
- 18 -
complete bead 16a of the end portion of the pipe 3a
is further formed with a frustoconical surface or
flank 15 which -tapers in a direction toward -the
axis of the end portion of the hose 1 and facilitates
the movement of the pallet 14a over the radially
outermost part of the bead 16a, along the frustoconical
flank 17a and into engagement with -the cylindrical
portion 21 of the external surface of the pipe 3a.
When the pallet 14a bears against the cylinclrical
portion 21a, the third or additional portion 20 of
the latching device 13a bears against the external
surface of the end portion of the hose 1 and urges
the material of such end portion agai.ns-t the rib 9a
as well as into the external groove lOa of the
section 5a. As can be seen in FIG. 2, the connector
2a can be provided with a complete annulus of
closely adjacent latching devices 13a to thus
ensure that the first section 4 of the connector 2a
is held in the end portion o~ the pipe 3a with a
required force as well as that the second sec-tion 5a
is maintained in pronounced sealing engagement with
the surrounding end portion of the hose 1 even
though the section 5a does not exhibit the ribs 10
of the sec-tion 5 shown in FIG. 1. The bias of each
web 12 is sufficiently pronounced to main-tain the
respective pallet 14a in strong frictional engagement
with the cylindrical portion 21 of the external
surface of the end portion of the pipe 3a which
latter, in turn, ensures -that the third or addi-tional
portions 20 of the latching devices 13a maintain at
-- 19 --
B
least some material of the elastically deformable
end por-tion of the hose 1 in the groove lOa and in
sealing engagement with the rib 9a. It will be
noted that, in contrast to the additional portion 1
of -the latching device 13 shown in FIGo 1 I the
third or additional portions 20 of the latching
devices 13a shown in FIG. 2 slope -toward the axis
of the hose 1 in a direction away from the end
portion of the pipe 3a. The force with which the
third or additional portions 20 of the latching
devices 13a urge the material of the end portion of
the hose 1 into the groove lOa of the second section
5a decreases somewhat as the pallets 14a ride
beyond the crests between the frustoconical flanks
15 and 17a of the bead 16a, but such force is still
sufficient to ensure reliable retention of the first
section 4 in the end portion of the pipe 3a, i.e.,
to prevent accidental separation of the parts 3a and
2a or a separa-tion of such parts in response to the
exertion of a relatively small axially oriented
force upon the end portion of the pipe 3a and/or upon
the connector 2a. Furthermore, the deforming action
of the third or additional portions 20 upon the end
portion of the hose 1 can be readily selected in
such a way that the end portion of the hose 1
cannot be readily or accidentally separated from
the section 5a while the pallets 14a bear against the
cylindrical por-tion 21 of the ex-ternal surface of the
end portion of the pipe 3a. The pallets l'la are
biased against the cylindrical portion 21 under the
- 20 -
ac-tion of the elastically deformed webs 12 as well
as under the action of the elastically deformed
end portion of the hose 1, i.e., of that part of
-the hose which is engaged by the third or additional
portions 20 of the latching devices 13a.
The necessary deformation of the end
portion of the hose 1 (and the penetration of the
material of such end portion into -the groove lOa)
is ensured by appropriate selection of the dimensions
of various componen-ts of the coupling which is shown
in FIG. 2. Thus, the diameter of the circle which
is defined by the innermost parts or tips of the
third or additional portions 20 of the latching
devices 13a shown in FIG. 2 when the pallets 14a
of such latching devices engage the cylindrical
portion 21 of the external surface of the end
portion of -the pipe 3a is less than the maximum
diameter of the second section 5a plus two wall
thicknesses of the hose 1 in undeformed condition
of the latter. In fac-t, adequa-te deformation of the
end portion of the hose 1 is assured even if the
diameter of the circle defined by the tips of the
third or additional portions 20 is less than the
diameter of the surface a-t the bottom o:E the groove
lOa plus two wall thicknesses of the hose 1 in
undeformed condition of the latter. The deformed
end portion of the hose 1 bears against the rib
9a as well as against the circumferentially complete
edge at the inner end of the groove lOa (as considered
in the axial direction of the section 5a), and
- 21 -
~5~
such deformation of the end portion of the hose 1
at both axial ends of the groove lOa ensures that
the end portion of the hose is mechanically held
against axial movement with reference to the second
section 5a (and/or vice versa) with a rather
pronounced force as well as that the parts 2a and
1 remain in continuous sealing engagement with one
another.
If the coupling of FIG. 2 is subjected
to the action of an axially oriented force which
tends to separate the second section 5a from the
hose 1, e.g., to the action of a force which tends
to move the end portion of the hose 1 axially and
away from the end portion of the pipe 3a and/or
vice versa, the pallets 14a of the latching
devices 13a slide along the frustoconical flank 17a
of -the bead 16a toward the crest between the
flanks 15 and 17a so that the tips of -the third or
additional portions 20 move nearer to the axis of
the second section 5a and subject the end portion
of the hose 1 to an even more pronounced deforming
action. Thus, the resistance which the third or
additional portions 20 of the latching devices 13a
offer to separation of the hose 1 from the second
section 5a of -the connector 2a increases in response
to an increase of the force which tends to separate
the hose 1 from the connector 2a. Such increase in
the resistance oE -third or addi-tional por-tions 20
to separation of the hose 1 from the second section
5a takes place simultaneously with an increase of the
- 22 -
resistance which the pallets 14a of the latching
devices 13a offer to separatlon of the first
section 4 from the end portion of the pipe 3a. This
will be readily appreciated by bearing in mind that
the pallets 14a begin to engage the frustoconical
flank 17a as soon as they are forced to leave the
cylindrical portion 21 of the external surface of
the end portion of the pipe 3a on their way toward
the end face of the pipe. Thus, the coupling of
FIG. 2 can be disengaged only in response to the
exertion of a force which suffices to subject the
latching devices 13a to a deformation such as is
required to slide the tips of the pallets 14a over
the frustoconical flank 17a and onto the frustoconical
flank lS of the bead 16a. Separation of the first
section 4 of the connector 2a from the end portion
of the pipe 3a can be facilitated by an operator
who urges the third or additional portions 20 deeper
into the material of the end portion of the hose 1,
i.e., nearer to the external surface of the second
section 5a. This can be effected by finger pressure
or by using a flexible element which is placed
around the outer sides of the third or additional
portions 20 and is tightened around the coupling.
It is equally within the purview of the invention to
provide each of the latching devices 13a with an
additional portion corresponding to the portion
18 of the latching device 13 to facilitate separation
of the first section 4 of the connector 2a from the
end portion of the pipe 3a. Such additional portions
~-5~
facilitate the task of causing the third portions 20
to move nearer to the periphery of the second
section 5a.
FIG. 2 shows that the internal surfaces
or inner sides 22 of the pallets 14a slope toward
the axis of the pipe 3a in a direction away from the
end portion of the hose 1 when the pallets 14a
engage the cylindrical portion 21 of the external
surface of the pipe. The slope of the surfaces or
sides 22 is more pronounced than the slope of the
frustonical flank 17a of the bead 16a. Such
inclination of the inner sides 22 of the pallets
14a renders it possible to replace the bead 16a with
a bead of the type shown in FIG. 1, i.e., with a
bead having a frustoconical flank 15 and a radial
flank or shoulder corresponding to the shoulder 17
shown in FIG. 1. The inner sides 22 of the pallets
14a can slide over the radial shoulder 17 when the
first section 4 of the connector 2a shown in FIG. 2
is in the process of being separated from a pipe
having an end portion of the type shown in FIG. 1
(i.e., with a bead 16 having a frustoconical flank
15 and a radial shoulder 17). Still further, it
is possible to replace the pallets 14a of the
la-tching devices 13a with pallets (14) of the type
shown in FIG. 1, i.e., with pallets whose inner
sides extend substantially radially of the end
portion of the pipe 3 or 3a when such pallets
engage the cylindrical surface portion 21 of the pipe,
depending on the configuration of the bead on -the
- 24 -
~5g~
pipe which is used with a connector 2a having an
annulus of latching devices 13a with pallets 14
in lieu of pallets 14a. The just described
modification can be resorted to with particular
advantage when the end portion of the pipe has a
bead 16a, i.e., a bead with two mutually inclined
frustoconical flanks 15 and 17a.
It will be seen that the outer sides of
the latching devices 13 and 13a are readily
accessible from the exterior of the respective
coupling. This affords convenient access to the
portion 18 of the latching device 13 and to the
portions 20 of the latching devices 13a for the
purpose of facilitating separation of the first
section 4 of the connector 2 or 2a from the end
portion of the pipe 3 or 3a.
The coupling of FIG. 3 differs from the
coupling of FIG. 2 in that the first portion of each
latching device 13a comprises or constitutes a
spherical joint enabling the portions 14a and 20
to pivot in a plane which includes the axis of the
coupling, i.e., about an axis which is tangential
to the connector 2b. The web 12a of the first
portion of each latching device 13a shown in FIG.
3 has a sphere 23 extending in-to a complementary
socket 24 of the connector 2b. I-t will be appreciated
that the connec-tor 2b of FIG. 3 can carry two or
more latching devices 13a of the type shown in FIG.
2 and two or more latching devices 13a wi-th
spherical joints 23, 24 and webs 12a.
- 25 -
~l~5~
The couplings of FIGS. 2 and 3 exhibit the
advantage that the latching devices 13a not only
secure the connector 2a or 2b to the pipe 3a but
also that their portions 20 constitute component
parts of the means for mechanically locking the end
portion of the hose 1 to the section 5a of the
connector 2a or 2b. Thus, the clamp 11 of -the
coupling which is shown in FIG. 1 can be omitted.
Moreover, and as explained above, the resistance
which the portions 20 of the latching devices 13a
offer to separation of the hose 1 from the section
5a of the connector 2a or 2b increases in response
to increasing tendency of the end portion of the
pipe 3a to become separated from the section ~ of
the connector 2a or 2b at a time when such separation
is not desired. Still further, the preferably
elastic material of the end portion of the hose 1
assists the webs 12 and 12a of FIGS. 2 and 3 in
maintaining the pallets l~a of the latching devices
13a in pronounced engagement with the cylindrical
portion 21 of the external surface of the pipe 3a
because the material of the hose 1 tends to pivot
the latching devices 13a in a counterclockwise
direction, as viewed in FIG. 2 or 3, through the
medium of the portions 20. In fact, the webs 12
or 12a of FIG. 2 or 3 need not be elastic at all
(i.e., they need not contribute to retention of the
pallets l~la in engagement with -the respective
cylindrical portions 21) because such function can
be taken over entirely by the material of the end
- 26 -
portion of the hose 1.
The porti.ons 20 of the latching devices
13a can establish a reliable seal be-tween the end
portion of the hose 1 and the sec-tion 5a of the
connector 2a or 2b even if the groove lOa of FIG.
2 or 3 is omitted. However, the provision of such
groove contribu-tes significantly to the reliability
of sealing action which is established between the
external suxface of the section 5a and the internal
surface of the end portion of the hose 1. Flexing
of a part of the end portion of the hose 1 into the
groove lOa under the action of portions 20 of the
latching devices 13a has been found to greatly
reduce the likelihood of leakage of a gaseous or
hydraulic fluid between the section 5a and the hose
1. Furthermore, reliability of the sealing action
between the hose 1 and the section 5a increases
when the end portion of the pipe 3a tends to become
separated from the section ~ of the connector 2a or
2b due to the aforediscussed cooperation between the
pallets 14a and the frustoconical flank 17a of the
bead 16a. The inclination of the inner sides 22
in the aforediscussed manner also contributes to a
more reliable cooperation between the palle~s 14a and
the bead 16a in enhancing the sealing action of
portions 20 when the end portion of the pipe 3a
tends to become separated from the section ~ of the
connector 2a or 2b or vice versa. However, and as
already mentioned above, the pallets 14a can
cooperate wi-th the flank 17a to enhance the
- 27 -
~5~
sealing action of the por-tions 20 even if the inner
sides of the pallets 14a extend radially or subs-tantially
radially of the end por-tion of the pipe 3a.
FIG. 4 illustrates a fourth coupling
whexein the first section 4a of a modified connector
2c is surrounded by the end portion of the pipe 3
and the second section 5b of the connector 2c
surrounds the end portion of the hose 1. The
sections 4a and 5b are integrally connected to each
other by a radially extending third section or
flange 26 having an annular end face 25 which
abuts against and is vulcanized or otherwise
bonded to the adjacent end face of the end portion
of the hose 1. The connector 2c can be made of
polyamide. If desired, the cylindrical external
surEace of the end portion of the hose 1 can be
bonded to the cylindrical internal surface of the
second section 5b to even further reduce the
likelihood of separation of the parts 1, 2c and/or
leakage of fluid between such parts. The hose 1
can be vulcanized to the section 5b and/or flange 26
by heating to a temperature between 170 and 180C.
and subsequent cooling. The bonding operation
renders it possible to simplify the design of the
section 5b, i.e., such section need not be provided
with one or more external ribs and/or grooves.
The sealing element of the coupling which
is shown in FIG. 4 is a sleeve-like element 7a
having a cylindrical internal surface which is
bonded (e.g., vulcanized) to the cylindrical external
- 28 -
~5~
surface of the section 4a and one or more elastically
deformable circumferentially complete external
lips 27 in sealing engagement with the cylindrical
internal surface 8 of the end portion of the pipe 3.
The external surface of the sealing element 7a is
further provided with a circumferentially complete
bead 28 whose outer diameter (in undeformed
condition of the sealing element 7a) exceeds the
diameter of the internal surface 8 so that the bead
28 undergoes at least some deformation and sealingly
engages the surface 8 when it is forced ~either
entirely or in part) into the end portion of the
plpe 3. The bead 28 is immediately adjacent to the
respective side of the third secti.on or flange 26
of the connector 2c.
The latching device 13 of the coupling
shown in FIG. 4 is analogous to the latchiny device
13 of FIG. 1. ~lso, the bead 16 at the free end of
the end portion of the pipe 3 is similar or
identical with the bead 16 of the pipe which is
shown in FIG. 1. The only difference between the
latching devices 13 of FIGS. 1 and 4 is that the
additional portion 18 of the latching device shown
in FIG. 4 extends in substantial parallelism with
the axis of the coupling when the pallet 14 engages
the radially extendiny shoulder 17 of -the bead 16.
FIG. 5 shows another coupling which
distinguishes from the coupling of FIG. 4 in that
the second section 5c of the connector 2d has the
same inner and outer diameters as the :Eirs-t section
s~
4a and is received in the end portion of the hose 1.
Furthermore, the sleeve-like sealing element 7b of
the coupling which is shown in FIG. 5 has several
external sealing lips 27 in sealing engagement with
the cylindrical internal surface 8 of the end
portion of the pipe 3. The external surface of the
second section 5c is vulcanized or otherwise
bonded to the internal surface of the end portion
of the hose 1, and the external surface of the
section 4a is vulcanized or otherwise bonded to the
internal surface of the sealing element 7b. The
inclination of the additional portion 18 of the
latching device 13 which is shown in FIG. 5
resembles that of the additional portion 18 shown
in FIG. 1. The weh 12 of the latching device 13
of FIG. 5 is flanked by the end faces of the end
portions of the pipe 3 and hose 1.
Referring to FIG. 6, there is shown a
further coupling wherein the latching device 13b
is not integral with a metallic connector 2e.
Furthermore, the sleeve-like sealing element 7c is
integral with the end portion of the hose 1 and has
two deformable external lips 27 in sealing
engagement with the cylindrical internal surface 8
of the end portion of the pipe 3 which is identical
with the pipe 3 of FIG. 1. The cylindrical first
section 4b of the connector 2e has a radially
outwardly extending collar 29 which abuts against
the end face of the sealing element 7c, i.e.,
against the end face of the hose 1. The cylindrical
- 30 -
~5C~
external surface of the cylindrical section 4b
and/or 5c of the connector 2e is bonded (e.g.,
vulcani~ed) to the cylindrical internal surface
of the end portion of the hose 1. The manner in
which the preferably thermoplastic material of the
hose 1 can be bonded to the metallic material of the
connector 2e is well known in the art and need not
be described here.
The latching device 13b is integral with
a metallic ring 30 whose internal surface is
vulcanized or otherwise bonded to the end portion
of the hose 1. The material of the ring 30 and
latching device 13b can be identical with the
material of the connector 2e. The latching device
13b comprises a first portion or web 12b which is
elastically deformable and is integral with the
ring 30, and a second portion including the pallet
14 which can engage the radial shoulder of the bead
at the free end of the end portion of the pipe 3.
The end portion of the hose 1 constitutes a
means for indirectly attaching the latching device
13b to the connector 2e. The ring 30 can carry two
or more discrete latching devices 13br e.g., a
complete annulus of closely adjacent latching devices.
~ n advantage of the coupling of FIG. 6,
wherein the sealing element 7c is integral with the
end portion of the hose 1, is that the sealing
element need not be machined and mounted as a
separate part. This con-tributes to a reduction of
the initial and assembly cost of the coupling.
- 31 -
~s~
Moreover, the seal between the pipe 3 and hose 1 is
very reliable because an integral part (sealing
element 7c) of the hose is moved into direct
sealing engagement with the end portion of the pipe.
An advantage of the establishment of a
bond between the end portion of the hose 1 and the
respective section or sections 5b-26, 5c) of the
connector 2c, 2d or 2e is that such bond invariably
prevents leakage of fluid between the connec-tor
and the hose as well as that the fluidtight connection
between the connector and the hose does not require
the provision of additional parts (such as the
clamp 11). Moreover, those surfaces or end faces
of the hose and connector which are to be bonded to
each other are preferably smooth cylindrical or
radially extending surfaces which require much less
machining or other treatment than the making of ribs
and/or grooves in the external surface of the
respective section of the connector. Still further,
vulcanizing is a relatively simple operation which
can be carried out in a fully automatic way in
contrast to the application of a clamp or the like
which can also be automated but at a higher cost.
It has been found that the establishment of bonds
by vulcanizing or another suitable technique
ensures the establishment of connections which are
highly reliable at pressures which are anticipated
in pipelines employing the improved coupling.
Insertion of the second section (5c) of
the connector 2d or 2e into the hose 1 in a manner
~5~Bs~
as shown in FIGS~ 5 and 6 is desirable and advantageous
on the additional ground that -the normally radially
expanded end portion of the hose contributes to the
establishment of an even more reliable seal between
the connector and the hose.
The provision of one or more lips 27 on
the sealing element 7a, 7b or 7c is desirable and
advantageous because the inner diameter of the end
portion of the pipe 3 need not be selected with a
high degree of precision, i.e., the deformable lip
or lips compensate for eventual deviations of the
diameter of the internal surface 8 from an optimum
diameter. Moreover, the internal surface 8 need
not be machined with a high degree of precision.
FIGo 7 shows a coupling wherein the connector
2f consists of sheet metal and a portion of its
second section 5c surrounds -the respective end
portion of the sleeve-like sealing element 7d.
The second section 5c includes a radially outwardly
extending flange 31 which is disposed be-tween the
end face of -the end portion of the hose 1 and the
adjacent end por-tion of the sealing element 7d.
The latching device 13b is integral with the flange
31. The sealing element 7d has a bead 28 corresponding
to that which is shown in FIG~ 4 and a set of
coaxial axially spaced sealing lips 27 which engage
the cylindrical in-ternal surface 8 of -the end
portion of the pipe 3. The latter is identical with
the pipe 3 of FIG~ 1~ The end face of the hose 1
is bonded (e.g., vulcanized) to the flange 31 of the
connector 2f. The axial length of the seallng element
7d approximates that of the connector 2f; the left~
hand end face of this sealing element abuts agains-t
the radially outwardly ex-tending collar 29 of the
firs-t section 4b of the connector 2f. It is
preferred to establish a permanent bond (e.g., by
vulcanizing) between the cylindrical internal
surface of the element 7d and the cylindrical
external surface of the connector 2f all the way
between the flange 31 and collar 29.
The coupling of FIGS. 8 and 9 is similar
to the coupling of FIG. 7 except that the bead 28 of
the sealing element 7d is replaced with a cylindrical
end portion 32 which is confined between two concentric
parts of the second section 5c. The end por-tion 32
of the sealing element 7e can be sealingly clamped
between the outer part 30 and the radially inwardly
adjacent inner part of the second section 5c.
The part 30 is connected with the inner part of the
second section 5c by the radially extending flange
31 whose outer side is bonded (e.g./ vulcanized)
to the adjacent end face of the hose 1. In addition
to having its end portion 32clamped between the
parts of the second section 5c, the internal surface
of the sealing element 7e can be bonded to the
external surface of the first section ~b or to the
external surface of the first section ~b as well
as -to the external surface of the radially inner
part of the second section 5c of the metallic
connector 2f. FIG. 9 shows that the flange 31 of
- 3~ -
r~
the second section 5c of the connec-tor 2f i.s
integral with three equidis-tant latching devices
13b with elastic webs 12b and second portions
including pallets 14 which normally engage the
radial shoulder of the bead including the frustoconical
flank 15 shown in FIG. 8. It is clear that the
number of latching devices 13b can be reduced to
less than three or increased to four or more.
An advantage of the coupling which is shown
in FIGS. 8 and 9 is tha-t -the connector 2f is not
only sealingly bonded to but is also in mechanical
sealing engagement with (the portion 32 oE the)
sealing element 7e. Moreover, the part 30 can
resile with the webs 12b so that the elasticity
of each latching device 13b in the region of the
parts 12b and 30 is quite pronounced and the pallets
14 can more readily slide along the flank 15 on
their way -toward engagement with the readial
shoulder at the free end of the end portion of the
pipe 3. Still further, end portion of the hose 1
can be bonded to -the flange 31 (as actually shown
in FIG. 8) or to the external surface of the part 30
of the second section 5c~ The bonding of the end
face of the hose 1 to -the flange 31 in a manner as
shown in FIG. 8 is preferred a-t this time because the
internal surface of the hose 1 is at leas-t
substan-tially flush wi-th the internal surface of the
connector 2f so tha-t -the parts 2f and 1 do no-t
in-terfere with -the flow of a Fluid medium through the
assembled coupling.
~5~B
FIG. 10 shows a coupling which is similar
to the coupling of E'IGS. 8 and 9 excep-t that the
rlng 30 which carries one or more latching devices
13b is indirectly affixed to the connector 2e by
the right-hand end portion 32 of the sealing
element 7e. The left-hand end portion of the
sealing element 7e has a set of five sealing
lips 27 in contact with the cylindrical internal
surface of the pipe 3. The end portion of the hose
1 surrounds and is bonded to the ring 30, the internal
surface of the ring 30 is bonded to the external
surface of the second section 5c, and the internal
surface of the sealing elemen-t 7e is bonded to the
external surface of the connector 2e of FIG. 10.
Referring to FIG. 11, there is shown a
coupling comprising a metallic pipe 3b whose end
portion has at least one opening 33, namely one
opening for each latching device 13c. The latter
is integral with the connector 2d which is an
elongated cylinder having a first section 4a
bonded to the internal surface of the sleeve-like
sealing element 7b and a second section 5c bonded
directly to the internal surface of the end portion
of the hose 1. FIG. 11 shows that the outer side
of the latching device 13c is curved outwardly and
away from the sealing elemen-t 7b so that the device
13c is automatically depressed radially inwardly by
pivoting in the region of its web 12 when the end
por-tion of the pipe 3b is slipped over and beyond
the sealing element 7b, i.e., when the pipe 3b is
~5~
moved in a direction to -the right and the parts 1,
2d and 7b are held against axial movement, when the
parts 1, 2d and 7b are moved axially to the left
and the pipe 3b is held against axial movement or
when the pipe 3b is moved to the right and the
parts 1, 2d, 7b are moved to the left, as viewed in
FIG. 11. The second or outer portion o the latching
device 13c of FIG. 11 is depressed by the end face
of the end portion of the pipe 3b when such end
face advances beyond the sealing element 7b to move
toward and into abutment with the end face of the
hose lo The person assembling the coupling of
FIG. 11 must ensure that the latching device 13c is
aligned with the opening 33 so that the second portion
of this device can move radially outwardly under the
action of the elastically deformable web 12 when
the device 13c registers with the opening 33. The
surface 34 bounding a portion of the opening 33
reduces the likelihood of accidental separation of
the end portion of the pipe 3b from the lips 27
of the sealing element 7b and from the latching
device 13c. The surface 34 performs the function
of the radial shoulder 17 which is shown in FIG. 1.
The internal surface oE the end portion of
the hose 1 is bonded (e.g., vulcanized) to the
external surface of the second section 5c oE the
connector 2d of FIG. 11. The internal surface of
the sealing element 7b is bonded to the external
surface of the first section 4a. As shown ln FIG.
11, the end face of the hose 1 can actually abut
- 37 -
against the end face of the pipe 3b.
FIG. 12 illustrates a modlfication of the
coupling which is shown in FIG. 11. The main
difference is that the end portion of the hose 1
is received between the end portion of the pipe 3b
and the second section 5c of the connector 2d.
The external surface of the second section 5c is
bonded to the internal surface of the end portion
of the hose 1, and the internal surface of the
sleeve-like sealing element 7b is bonded to the
external surface of the first section 4a. The
coupling of FIG. 12 can establish a highly satisfactory
seal between the end portions of the pipe 3b and
hose 1.
FIG. 13 shows a second modification of the
coupling which is illustrated in FIG. 11. The
connector 2d has a relatively short first section
4a whose external surface is bonded to the sleeve-
like sealing element 7f and an even shorter second
section 5c including a radially outwardly extending
web 12 constituting an integral first portion of the
latching device 13d. The second portion of the
latching device 13d is nearly completely received
in the opening 33 of the end portion of the plpe 3b
and abuts against the suxface 34 to be thereby
held against accidental or unintentional disengagement
from the end portion of the pipe. The end face of
the end portion of the hose 1 is bonded to a portion
of or to the entire web 12. In the embodiment of
FIG. 13, the opening 33 of the end por-tion of the
- 38 -
~s~
pipe 3b is nearly completely filled by the second
or outer portion of the latching device 13d. The
coupling of FJG. 13 can be modified by replacing
the connector 2d with a connector 2f of the type
shown in FIG. 8 but the configuration of the second
portion of the latching device preferably remains
unchanged so that such second portion can fill or
nearly fill -the opening 33 in the end portion of the
pipe 3b. The section 5c of the connector 2d shown
in FIG. 13 can be provided with a complete annulus
of latching devices 13d which are bonded to -the end
face of the hose 1 to ensure that the connector 2d
invariably shares all axial movements of the hose
and vice versa. As mentioned above, the sealing
element 7f of FIG. 13 is bonded to the section 4a.
The coupling of FIG. 14 differs from the
coupling of FIG. 13 in that the second or outer portion
of the latching device 13e fills only a part of the
opening 33 in the end portion of the pipe 3b. As
can be readily seen in FIG. 14, the second portion
of the latching device 13e slopes outwardly and
away from the periphery of the end portion of the
hose 1 in a direction away from the sealing
element 7f. The purpose of the surface 34 in the
opening 33 is the same as the purpose of the radial
shoulder 17 in the coupling of FIG. 1 or of the
surface 34 in the coupling of FIG. 11.
An advantage of the couplings which are
shown in FIGS. 11 to 14 is that -the free end of the
pipe 3b need not be provided with an external bead
- 39 -
but merely with an opening 33 for each of the latching
devices 13c, 13d or 13e or with one opening for two
or more neighboring latching devices. Furthermore,
the latching devices 13c, 13d and 13e are much
si~pler and hence less expensive than the previously
described latching devices.
All of the illustrated couplings exhibit
the advantage that the la-tching devices are at least
indirectly carried by the connector. This reduces
the overall cost of the couplings and simpli~ies the
assembly of their parts. In practically all embodiments
of the invention, the connector can be assembled
with the latching device or devices, with the sealing
element and with the hose in the manufacturing plant
so that its first section is merely pushed into the
end portion of the pipe 3, 3a or 3b in order to
complete the assembly o~ the coupling.
- 40 -
