Note: Descriptions are shown in the official language in which they were submitted.
~L259354
This invention relates to a coupling for a
hose.
A proposed hose coupling includes a
connecting member on ~ihich an end po~tion of a hose
can be pushed, and an e'astic clamping ring, with
the connecting member being provided on its outside
with a holc.ing rib which ex-tends therearound. The
ront side .surface OI the holding rib, which is
directed towards the push-on end of the connecting
me~!~er decreases in diameter towards the push-on end
for the end portion of the hose to be pushed on
to the rib over the front side surfaces. The clamping
rin(J surrounds the pushec.-on end portion of -the ho.se,
when the latter is on the connecting member~ in t:he
re~.ion of the holding rib, is shaped so that it can
be pushed, together with the hose, ovex the holding
rib, has closed peripheral edge portions at the
axial ends, and is provided with slots which pass
radially therethrough, which exter.d ir the axial
directlon of the cl.amping ring and whi.ch are
uniformly distributed in the peripheral directlon.
In a known hose coupling of this kind, the
rear side face of the holding ring which is remote
from the push-on end of the connectirg member e~tends
in a radial plane. ~t the axially forward and rear-
ward ends, the clamping ring has a respective irwardly
prcjectirg ar!nu~ar bead. The front bead is shaped
to press the end portion of the hose, which is fitted
on to the con.nect.ing member, against the decreasing
diameter front side surface of the holding rib and the
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~Z~9354
rear annular bead is shaped to press the end portion
against the cylindrical surface of the connecting
member, which adjoins the radial side surface of the
holding rib. The slots in the clamping ring are
axially shorter than the axial length of the holding
rib and web portions between the slots are compara-
tively thick in the radial direction, the thickness
thereof increasing on the inside towards the ends so
that, in conjunction with their axially short
lG dimensions, they are virtually inflexible in the
radial direction and their gripping force in the
region of -the holding rih is comparatively small.
This has an adverse effect on the sealing action and
the degree with which the hose i5 secured against
being pulled axially off the connecting member.
A hollow space in which there is no sealing
effect may be formed in the region between the rear
annular bead and the radial face of the holding rib,
between the cylindrical outside surface of the
connecting portion and the hose. ~efore the hose is
pushed on to the connecting member, the clamping
ring is fitted over the hose and then the hose and
the clamping ring are together pushed over the
connecting mem.ber for carrying the hose. In order to
permit the hose and the clamping ring to be easily
pushed on, the inside diameter at least of the radially
inwardly projecting annular bead on the clamping ring.
being the annular bead which leads in the direction
in which the hose is pushed Gn to the connecting
member, must be substantially larger than the outside
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12S93S4
diameter of the holding rib so that the clamping
force in the assembled condition, between the front
annular bead and the cvlindrical outside surface of
the connecting portion, is possibly too small, for
securing the hose in position in the axial direction
and providing a seal, in an adecluate fashion in
spite of the above-mentioned hollow space. If on the
other hand the inside diameter of the front annular
bead is smaller, then an excessively high force is
required to push the hose on to the connecting member,
and it is possible that that force cannot at least be
applied manually.
rrhere is thus a need for a generally
improved hose coupling which provides a better sealing
action and axial securing effect, with the hose and
the clamping ring being easier to push on to the
connecting member and preferahly with the clamping
ring being able to adjust to thermal expansion of the
hose material and shrinkage thereof due to cooling.
According to the present invention there is
provided a hose coupling including a connecting member
on which an end portion cf a hose can be pushed, which
connecting member is provided on its outside with a
holding rib which extends therearound, with the front
side surface of the holding rib, which is directed
towards the push-on end of the connectlng member,
decreasing in diameter towards said push-on end for
the end portion of the hose to be pushed on to the rib
over said front side surface, and an elastic clamping
ring for surrounding the pushed-on end ~ortion of the
12~9354
hose, when the latter is on the connecting member) in
the region of the holding rib, which ring is shaped
so that it can be pushed together with the hose, over
the holding rib, has closed peripheral edge portions
at the axial ends, and is provided with slots which
pass radially therethrough, which extend in the axial
direction of the clamping ring and which are uniformly
distributed in the peripheral direction, wherein the
rear side surface of the holdin~ rib decreases in
diameter away from said push-on end of the connectin~
member, the clampin~ rings slots extend at least over
the full axial length of the holdin~ rib, web portions
between the slots are elastically flexible in the
radial direction, and the mean diamet2r and the
inside diameter of the clamping ring in the region of
the web portions are constant, at least over the
major part of the axial length of the holding rib,
before a hose end and the clamping ring are pushed
on to the connection member, and such that, after
the hose end has been pushed on to the connecting
member, the web portions are elastically bulged out
in their axially central region with which they bridge
over the crest of the hold.ing rib, and apply a spring
biassi~g effect-to the hose.
The fact that the rear side surface of the
holding rib, which is remote from the push-on end
of the connecting member, decreases in diameter,
i.eO tapers, eliminates a hollow space or cavity
between the hose and the connectin~ member an~, bv
virtue of the long web portions which bend radially
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~2~935D~
outwardly at the region of the holding rib, the hose
is pressed firmly against the holding rib and the
connecting member over a greater axial length, with
the web portions producing the spring biassing effect,
so as to provide a better sealing effect and an axial
securing action. If therefore the front end of the
clamping ring carries an annular bead which projects
radially inwardly, -the inside diameter thereof can
be made comparatively large. Possible, a radially
inwardly projecting annular ~ead at che front end of
the slamping ring can be entirely omitted. This
facilitates pushing the hose and the clampinq ring
jointly on to the connecting member. In 'chis case,
the long elastic web portions facilitate the operation
of pushing the hose on to the connecting member,
while also providing for a spring biassing or pre-
stressing effect in a comparatively long axial region
of the end portion of the hose, which is pushed on to
the connecting member, so that ln that region the
clamping ring can resiliently yield to thermal
expansion of the hose material and can retighteIl in
the event of shrinkage of the hose material, caused
by cooling. This gives a further increase in the level
of security of the sealing action produced.
It is also desirable for the rear side
surface of the holding rib to be provided with
shallow teeth extending therearound. This even
further improves the axial securing ackion.
The teeth may be of a sawtooth configuration
in axial cross-section and each sawtooth side face
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1~5~354L
which is remote from the push-on end of the
connecting pGxtion may lie in a radial plane. This
tooth configuratiorl on the one hand facilitates the
operation of pushing the hose onto the connecting
member while on the other hand it resists, to a
particularly high degree, the hose bein~ pulled or
slipping off the connecting mernber.
The slots extend at least over the full
axial lenyth of the holdirg rib. With this configuration,
the web portions press the hose material resiliently
against the holding rib over thc entire axial length
thereof, which gives a correspondingly higher level
of security and certainty of sealing action and an
improved axial securing effect.
It is also desirable for the angle of
inclination of the rear side surface of the
holding rib to be less than that oE the front side
surface of the holding rib, and for the axial
length of the two side surfaces to be substantiall~
the same. This makes it easier for the connecting
member to be introduced into the hose and makes it
easier for the hose to be pushed onto the connecting
member. I~onetheless, the predominant part of the hose
which is pushed on to the connecting member, in
particular the front end thereof, bears under an
inherent biassing or prestressing force against the
connecting portion, thereby increasing the sealing
effect~
The axial length of the clamping ring may
be such that the end of the clamping ring which is
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~lZ5~3~9L
remote frGm the pushed-on end of the hose lies in
front of the push-on end of the connecting member.
In that way, the clamping ring resists the hose
material lifting away from the decreasing diameter
front side surface of the holding rib, even when the
hose is radially bent or deflected in front of the
push-on end of the connecting member.
The one peripheral edge portion of the
clamping ring may bear against the end face of the
pushed-on end of the hose. In that way, the
peripheral edge portion forms an abutment to prevent
the clamping ring from ~eing pushed on to the hose
too far.
The clamping ring is of a constant inside
diameter, before -the hose and the clamping ring are
pushed on to the connecting member, over the length
Gf the slots. This simplifies manufac.ure of the
clamping ring and ensures that, in their axially
central region with which they bridge over the
crest of the holding rlb, the web portions are
caused el.astically to bulge out and apply the desired
spring biassing effect to the hose.
In addition, the peripheral edge portion
of the clamping ring, which is bes.ide the rear side
of the holding rib, may be corrugated in the
peripheral directlon Th-.s permits the front end
of the clamping ring, consi.dered in the direction in
which the ring is fitted on to the connecting member,
-to enlarge, thereby facilitating pushing the clamping
ring into position on the connecting member.
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~ X5935~L
The latter ef~ect may also be achleved hy
the mean diameter of the clamping ring being constant
before the hose and the clamping ring are pushed on
to the connecting member, over a main portion of the
axial length of the clamping ring, and, in an
intermediate region, which adjoins the main portion
and which is adjacent to the peripheral edge portion
which is beside the rear side of ~he holding rib,
increasing in a directjon towards said peripheral
edge portion.
In this connection, the intermediate region
may be bent back radially outwardly and over the
outside of the claDIping ring so that the peripheral
edg~ portion which is beside the rear side face of
the holding rib surrounds the ~ain portion at a radial
spacing~ In this way, the clamping rin~ bears
constantly against the hose over its entire length
I~onetheless, it can eY~pand at its front end and can
easily be pushed over the holding rib, with the hose.
,o The peripheral edge portion of the clamping
ring, which is beside the rear slde face of the
holding rib, may be interrupted in the region hetween
two adjacent web portions, and the interruption may
be closed by a closure means. In this case~ t~le
closure means of the clamp-ng rincJ may be ope~ed
befcre the hose and the clamping ring are pushed on
to the connecting member, in order to facilitate this
operation.
The closure means may be a retaining or
detent closure. Such a -losure means is easy to handle.
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~2~93~4
~ n particular, the closure means may ~e
provided with portions which are formed on both ~ides
of the interruption ana which engage one behind the
other, thereby providin~ a closure means of simple
construc ;::ion .
A respeetive pro~eetion may be formed on
the per:ipheral edge portion having the interruption,
on both sides of the interruption, in the vicinity
thereor. The projeetions faeilitate the operation of
elosing the clo~ure means, as, for the purpo3es of
clo3ing the closure means, they only have to be
brought together in the peripheral c.irection.
In this arrangement, one proiection rnay
form the one closur2 portion so th~t there is no need
for an additional projection acting as a suppoxt
means for handling the closure means when closirlg same.
For a better understanding of the present
invention, and to show how the same may be carried
into effect, referenee will now be made, bv way of
example, to the aecompanying drawings, in whieh:-
Fig 1 is a view in axial seetion through ahose coupling accordi.ng to the invention,
Fig 2 is a view in radial section through
a elamping ring of the hose eoupling shown in Fig 1
Fig 3 is a perspective view OL part of a
c~amping ring of a hose coupling aceording to a seeond
embodiment of the invention,
Figs 4 to 9 are vlews in axial seetion of
clampin~ rings of hose -ouplings accord:ng to
further embodinlents of the invention, o~ a hose, and
~25935fl~
Fig 10 is a perspective view of a clamping
ring of a hose coupling according to anothe-c embodiment
of the inven-tion.
In the embodiment of the ln~Tention
illustrated in Figs 1 and 2 r the hose coupllng
comprises a connecting member or portion 1 and a
clarnping rlng 2 of elastic plastics material, a
hose 3 being clamped therebetween, by its en~
portion 4.
The connecting portion 1 has a holding rib
5 extending therearound, which begins at the push-on
end of the connecting portion 1 and terminates
approximately at the rearward end of the connecting
portiGn 1. ~ front side surface 7 of the rib 5
decreases in diameter towards a push-on end 6 of
the connecting member 1 and the rear side surface 8
of the rib S decreases in diameter away from the push-
on end 6. The angle of inclination of the front
side surface 7 is somewhat larger than the angle of
2~ inclination of the rear side surface 8 which is
provided with shallow teeth 9 ex~ending therearound.
The outside diameter of the tubular connecting portion
1 at the push-on end, being about 28mm, is somewhat
smaller than the inside diameter of the hose 3 in a
non-stressed condition, being about 29mm, in order to
make it easier for the hose 3 to be pushed on. The
outside diameter of the rearward end of the
connecting portion 1, at about 31mm, is somewhat
larger than the inside diamete-c of the hose 3 in the
unstressed condition. The side surfaces 7 and 8 are
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~ ~93~L
of approximately the same length of 20mm in the axial
direction, and are at an angle of about 7 and about
3 respectively. The l.argest outside diameter of the
holdlng rih 5 is about 33 mm. The teeth 9 are
substantially sawtooth-shape in cross-sect;.on.
Thei.r conical side face which is towards the push-on
end b extends over an axia' length of about. 1.5mr.
while the radial side face thereof extends over about
O.4mm. Th~ ancJle of inclination of the conical sides
of the teeth is therefore about 15.
rrhe clamping ring 2 has twenty-four slots
].2 which pas.s radially therethrough and which extend
in the axial direction as far as peripheral edge
portions in the form of annular beads 10 and 11.
~he slots 12 are defined by thin axial web portions
13 and are arrangec`t at unif~rm spacing from each
other in a distributed array arounc1 the periphery
of the clamping ring 2. The width of the slots is
about lmm. The annular beads 10 and 11 are closed
in the peripheral direction. ~he annular bead 11
bears with a radially inwardly projecting flange
portion aaainst the end face 14 of the end portion 4
so that the clampin~ ring 2 cannot be pushed further
over the end portion ~. Instead of the flange portion,
the hose 3 may be pro~ided, on its outside, with an
annular bead 15 to act as an abutment for the clamping
ring 2. Omitt.inc~ the radially inwardly proj~cting
flaIlge portion on t.he annular bead li. anc' forminq the
two annular beads 10 and 11 with the same inside
diameter as that of the web portions 13 further
-- 11 --
~S~335~
faciliiates manufacturing the clamping ring 2 and
pushins- the clamping ring 2 on to the hose 3, and
likewise jointly pushing the hose 3 and the clamping
r-ng 2 on to the connecting por-:ion 1, beyond the
holding rib 5.
The slots 12 extend at least over the full
axial length, and preferably over ~ore th~n the enti~e
axial ler~th of the holding rib 5, as illustrated.
The annular bead 10 is therefore disposed in front of
1~ the push-on end 6.
The inside diameter of the clampin4 ring 2
in the region of the slots 12, being about 38 mm, is
approximately equal to the outside cliameter of the
hose 3 in the non-stressed condition, wllich in turn
is laryer than the iargest outsi.1e dlameter of the
holdin~ rib 5.
The hose coupling shown in Figures 1 and ~
has the a~vantage that the end pGrtion 4 of the hose
3 is pressed a~ainst the connec-ting portion 1 over
the entire axial length of the end portion 4, ard the
hose material of the end portion 4 is under a
spring bias, as a result of the resiliercy ~f the ~eb
portions 13. The spring biassing effect ensures that
in the clamping region the clamping ring ~ yields to
thermal expansion of the hose material and prevents
the hose material from being subjected to an
excessive pressirg force. That counteracts permanent
deformation of the hose material. On the other hand,
after thermal expansion of the hose ma-terial and
subsequent cooling thereof, with the hose material
- 12 -
~XS9354
shrinki.ng, the arrangement also ensures that the
hose bears firmly against the connecting portion 1
because the elastic web portions spring back into
their starting positicn. Because the clamping ring
2 is longex than the end portion 4 of the hose 3 so
that the clamping ring 2 projects bevond the push-
on end 6 (towards the left in Figure 1), th~t
arrangement resists the end portion 4 lifting
radially away from the ccnnecting portion 1,
particularly the front side face 7, if the hose 3 is
radially deflected (bent) in front of the connecting
portion 1. In that case the clarnping ring 2, in
conjunction with the ta.pering, toothed cGnfiguration
of the rear side surface 8 of the holding rib 5,
affords a high degree of security in regard to the
end portion 4 being ~ulled or slipping axially off
the connecting portion 1, as could be the case when
thexe is a high fluid pressure in the interi.or of
the hose 3 or in the event of a high axia]. force
applied thereto from the out.side.
Before the hose 3 is pushed on to the pipe
portion 1, the clamping ring 2 is pushed over the
hose 3 into the illu.strated position. ~he hose 3 and
the clamping ring 2 are then jointly pushed on to the
connecting portion 1, i.n which respect a flan~e 16
at the rearward end of the connecting portion 1 or a
wall, corresponding to the flange 16, of a housing to
which the pipe pGrtion 1 is or exa~Lple inte~rally
connected serves as an abutment and prevents the hose
from bein~ pushed on too far. In other words, the
~' ,
;935~
arrangement ensures that the clamping ring 2 is in
a position with its rearward end (annular bead 10)
outside the connecting portion 1.
Figure 3 is a perspective ~iew on an
enlarged scale of a part of a second embodiment of a
clamping ring 2a. The clanping rin~ 2a may be used
in place of the clamping ring 2 for the hose coupling
shown in Fi.gure 1, and also comprises elastic
plast,ics material. ~nstea.d of the annular beads 10
and 11, ii has closed peripheral edge portions l.Oa and
lla. The peripheral edge portion lla which is beside
the side face 8 of the holding rib 5 is corrugated
in the peripheral ~,irection while the other perlpherc
edge portion lOa is smooth. Th2 clamping riny 2a
also has axial slots 12a which are defined by web
portions 13a. The axial length of the clamping ring
2a and the slots 12a and the inside diameter may
correspond ~o those of the clamping ring 2.
In this embodiment, the corrugated peripheral
edge po:rtion lla makes it easier for the clamping
ring 2a to be ~ushed on over the .holding rib 5.
In other respects, this arrangement has the same
advantages as the first embodiment described.
Figures 4 to 9 show further embodiments
of the clamping ring on the hose 3. In all clampincJ
rings 2b 'o 2g, the mean diameter (the mean value of
the inside and outside diameters) is constant over a
main portion of the axial length of the clamping
ring before the hose 3 and the clamping ring 2b to
2g a.re pushed on to the connecting portion 1 shown in
- 14 -
~A
~.X5~354
F.i.gure 1, which is not illustrated in Figures 4 to 9.
In an in-termediate region whlch adjoins the above-
mentioned main portion and which is adjacen~ to the
peripheral edge portion llb t~ llg which is
disposed beside the rear side face 8 oS the hoLding
rib 5 shown in Figure 1, the mean diamPter increases
in a direction towards the peripheral edge portion
llb to llg in order to facilitate pushin~ the hose
3 and the clampiny ring 2b to 2~ on to the connecting
portion 1, beyond the holding rib 5.
In the embodiments illustrated in Figures
4 and 5, the peripheral. ed~e portions llb to llc
e~tend at a spacing parallel to tlle peripheral
surface of the hose 3 (in the non-stressed condition),
while the edges o~ the peripheral edge porcions llb
and llc, which are leading when the ring is pushed
on to the connecting portion 1, are disposed in the
plane of the end. face 14 of ihe hose 3.
In the embodiments shown in E'igures 6 to 8,
the peripheral edge portions lld ~o llf which are the
leadin~ portions when ~he ring is plshed on to the
~onnecting portion 1 on the other hand bear against
the end face 14 so that they act as an abutment to
pre~.rent the clamping ring from being pushed on to the
hose 3 too far~
:~n tne embodiment illustrated in Fi~ure 9,
the bent or curved intermediate iegion is bent back
radia11y outward1y and o~er the outside o-E the
clamping r.ing 2g. Therefore1 the peripheral edge
portion llg whic~ after the component has been
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A
3 ~9354
pushed on to the connecting portion 1, is disposed
beside the rear side face 8 of the holding rib, also
extends around and at a radial spacin~ from ~he
nain portion of the clamping ring 2g, the main
portion beinc~ of cor,ctant diameter (before the
fitting operation . However, the web portivns 13g
be~r against tne hose 3 over a longer axial section.
As shown in Fi~ure 10, the peripheral edge
portion llh of the cla~ping ring 2h, which is the
leading edge in the fitting operation, has an
interruption 17 in the reg:ion of one of the slots
12h or between two adjacent web portions 13h.
Moreover, the slots 12 are closed at their ends as
the rear peripheral edge portion lG~ and, in the
remai.nin~ re~ion, also the peripheral edge portion
llh, are of a continuous confi.guration in the
~e.ripheral direction. The interruption 17 is
opened when the hose 3 and the clamping ring 2h are
pushed on to the connecting portion 1 in order to
facilitate that operation, and is closed after the
fi.tting operat:ion by a closure means 18.
The closure mean.s 1~) is a detent or snap
closure means havin~ two closure port..ons 20 and ~].
in the fcrm of substantially radial projections
which are formed on the peripheral edge portion llh
on both sides of the interrupti.on 17~ One closure
portion 20 i.s undercut on .its side which is towards
the .interruption 17 so that it is approximate:iy in
the shape of a question mark. The other closure
portion 21 is radial.ly somewhat shorter than the
- 16 -
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9359~
closure portion 20 and is undercut on ts side
which is remote from thé interruption 17. Another
rac~.j.al prc~ect:Lon 22 which is also formed close to
the interruption 17 on the undercut side of the
closure portion 22 facilitates the operation of
closing the cl.osure meansO In that arrangement, the
projections 20 and 22 are pressed together in the
peripheral direction manually or by means of a tool
until the substantially radially inwardly projectiny
part of the closure portion 20 has slipped over the
closure portion 21 and engages under the undercut
configurat.7On of the closure portj.on 210 The closnre
means may be opened again as desired by bending back
the radial secti.on oE the closure portion 20 in a
radiaJ. and out~ard direction.
~ ten the clamping ring 2h is pushed on,
radially inwardly projecting projections 23 of the
periphera]. ed~e portion llh bear against the end
face l~ of the hose 3 in order to prevent the clamping
ring 2h from being pushed or to the hose 2 too far.
~ odifications in the il].ustrated embodiments
may pro~ide for example that, in the embodiment
illustrated in Figures l and 2, the clamping ring 2,
instead of the annular bead ll, has a substantially
hook-shaped peripheral ed~e portion which first
extends somewhat radially inwardly and then somewhat
axially forwardly towards the axially opposite end
of the clamping ring 2 so that the cross-section
thereof (in an axial plane of the clamping ring 2) is
substantially in the for~.t c,f a U lying on its side.
A
~;~5935~
In all e~odiments moreover, the web portions,
instead of being of square or rectan~lllar cro~s-
section, ~ay be of a substantially U-~haped or
elliptical cross-section. Then, teeth which
correspond to the teeth 9 may also be formed on the
front side 7 of the holdin~ rib or only on the front
side 7.
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