Note: Descriptions are shown in the official language in which they were submitted.
The invention relates to a sealing or coupling device for two elements
which are to be concentrically connected to~ethQr with one element inserted
into the other - for example, a container and lid, two pipes, or a pipe snd
sleeve. The device comprises a clamp body for insertion into the radial space
between the two elements. At least one of the elements is bo~nded by a
conical surface facing the space, which conical sur~ace extends behind the
clamp body in the direction of the joint. The clamp body consists of elastic,
pliable, non-compressible material, which before installation has a thickness
greater than the maximum width of the space, in a rndial direction, and which
is located in the region of the conical surface.
Such a sealin~ or coupling device is described for example in the German
patent spacification 916268. The clamp body described has a prismatic profile
and s~ffers from the disadvantage that it moves axially durin~ the joining of
the two elements with resulting elastic deformations of the clamp body which
are considerable and which remain after both parts have been joined.
Conse~uently, they can lead to chronic deformities of the cla~p body which, in
terms of its re-use, is hardly satisfactory. In addition, the resistance to
pullin~ apart of the resultin~ connection leaves much to be desired.
; The object of the present invention is the provision of a sealin~ or
coupling device of the aforementioned type which, because it avoids
significant clamp body deformîties, provides improved resist~nce against
pulling apart of the resulting connection.
The above object is realized in the present invention by provision of
means for preventin~ an axi~l shift of the clamp body away from the conical
surace and by selecting the smallest distance between the conical surface and
the opposite surfsce (between which the clamp body is located) to be 0.1 to
0.5 times as great as the radisl thickness of the clamp body.
The clamp body is thus placed between the conical surface and the opposite
surface and a very small deformation is thus sufficient to effect the desired
securing and (as the case may be) sealing result. aelaxation of the body
material and chronic clamp body deformities need not therefore cause concern.
The clamp body has an annular form and i8 arrsn~ed on the conical surface
of the one part before the parts to be joined are fitted intv each other. The
other part may then very easily be slid in~ide or over the clamp body, because
the clamp body is Ible to slip to ~he necessary de~ree toward the widenin~
-- 1 --
space between the conical surface and the oppogite surface. It then rnakes
frictional contact with both surfaces with essent;ally the same initial
tension. A backwards separating movement of the two parts therefore results
in an increasing cumpression of the clamp body between the conical and
opposite surfaces. rhis is lim;ted by the deformability of the material used
in the manufac~ure of the clamp body and in no way allows, ~hen normal
materials are used, the clamp body to be forced through the smallest space
between the conical and opposed surfaces. In this case, "normal materiQls"
are understood to be mainly non-porous materials mad~ of elastic rubber
constituents.
In order to prevent an undesirable movement of the clamp body durinK
joinin~ of the parts, it is advantageous that there be provided a projection
which extends axially behind the clamp body from the part having the
aforementioned opposed surface. Such Q design, as well as bein~ simple to
manufacture, provides for good handling safety.
The support device can also be formed by an annular tensile element fixed
to the clamp body, ~hich abuts the part having the conical sureace. In such a
desi~n, the clamp body is effectively suspended, which ~ases its moulding
during the joining of the parts and therewith also the joining itself. A
particularly simple securement of the clamp body may be achieved in such a
design if the annular element is extended into a flange which lies against a
radially e%tended stop surface of the part featurin~ the conical surface. The
flQnge is thus visible from the exterior if the design allows, which enables
the subsequent checking of the quality of the resulting connection.
The tensile element, the flange and (if need be) the clamp body, can be
formed in one piece and can therefore all consist of rubber-elastic material.
Such a design is not only economical to produce, but moreover provides for an
a~ial shift of the clamp body toward the widenin~ space between the conical
surface and the opposite surface when the two parts to be joined are fitted
into each other. The joinin~ process is in this way greatly facilitated
without compromising the necessary static friction that occurs between the
clamp body and the surfaces pressin~ against it on either side. Such a design
further allows the later separation of the joined parts by providin~ the clamp
body on the side axially opposite the tensile element with a pulling tab, if
ths ~reatest radial distance between tho conical surEAce and the oppo~ite
.~ 3
surface is at least as lflrge as the radial extengion of the clamp body in an
unloaded state. In such a design, the clamp body may, aided by the pullin~
tab, be moved in the direction o~ the widening space between both par~s and
may finally be pulled out of the space. The separation of the parts can now
proceed unhindered, and the clamp body, by virtue of the elasticity of the
tensile element, can return to its previous position on the conical surface.
Re-joining of both parts as mentioned in the above designs is possible~
The surface opposite the conical surface can also have a conical shape and
can wrap around the clamp body in the direction of the joint. The clamp body
in such a design has a rigid structure on both sides. This can benefit the
reliability of the axial securement of the connected parts in critical
circumstances, especially if the introduction of vibr~tions into the
connection are of concern during normal use.
The conical and/or opposite surface and/or the clamp body can have ribs
extending toward the circumference and/or grooves in the region where the
surfaces meet, in order to improve the sealing properties, especially if
certain surface irre~ularities and/or impurities are present. Additionally,
there results an improvemen~ in the securing of the individual parts in the
axial direction.
The clamp body may assume flny profile; however, a circular design is
preferable. This is not only inexpensive to produce, but also makes possible
the acceptance of certain angular displacements between the parts to be
connected which are normally cylindrical in shape.
In designs in which the clamp body features a cross-sectional form
compatible with the pro~ile of the space bounded by the conical and opposite
surfaces, there occurs in eeneral an improved sealing result - especially if
the clamp body is designed with an annular membrane on the side facing the
joint, which under elastic initial tension lies against the inner one of the
concentrically joined parts. Similar designs recommend themselves for use
primarily in installations where the mutual connection of ~as and/or
waterpipes is involved.
In an advanta~eous design, the smallest distance between the conical
surface and the opposite surface is 0.2 to 0.3 times as gre~t as the maximu~
radial thickness of the clamp body. Without impedin~ the eflse of joining of
the two parts, a particularly ti~ht connection between the two parts results
within this range.
The angle enclosed by the conical surface and the axis of the sealin~ or
coupling device is generally 10 to 30 .
The proposed sealing or coupling device is excellently suited for cap
locks on containers or for the mutual joining of pipes. The device moreover
allows the anchoring of a variety of cylindrically shaped bodies in a space.
The clamp body comprises a conventional elastomeric sealant, for e~ample
nitrile-butadiene rubber, ethylene-propylene-terpolymer rubber, vinylide
fluoride hexafluoropropylene rubber, acrylonitrile-chloroprene rubber or
lQ epichlorohydrene rubber, preferably unfoamed. The surface of a clamp bodymade of such material may have a bubbly quality, so that a better surface seal
can be obtained, if the cl~mp and/or opposite surface features a highly
te~tured surface.
The hardness furthermore lies between 30 and 80 Shore A. Materials of
this kind are inexpensive to obtain and are easily made into the desired shape
by conventional means.
Where the invention is applied to the a~ial securing and sesling of a pipe
in a pipe supporting plate, the cl~mp body is connected by a tensile element
~similar in shape to a membrane) to a flange which has its front against the
supporting plate ~s well as having the outside of the clamp body against the
rearwardly widenin~ conical surface of the openin~. In this manner, the clamp
body when installed is practically unmovable and effects a good a~ial securing
of the pipe, which is contacted at least by the inner surface of the clamp
body as well as by the inner surface of the annular membrane associated
therewith. The latter has only a very small radial thickness. The pressure
of the sealed medium contributes directly to the pressure of the annular
membrane against the outer circumference of the pipe, as a result of which, in
addition to good a~isl securement, a ~ood seal is achieved. The fle~ibili.ty
of the membrane is in this instance oP critical importance. It ensures a
steady and solid contact between the clamp body and the received pipe, when
relative movements occur - for example as a re~ult of the int~oduction o~
vibrations o~ varying frequency. The proposed device is therefore
particularly suited for sealing and securin~ the heat exchan~e pipe of an air
conditioner in an automobile. At the same time, it lessens noise emlssions
from th~ relatively large surfaces of the individual parts.
~5~ 3
The radial fixin~ of the received pipe favours an especially ~ood
elasticity nnd softness that beneeits the Qcoustic insulation of the pipe.
This effect i5 primarily nchieved by the continuing of the rndial ixture of
the pipe within the support plate hole to be exclusively between the conical
surfacs of the hole and the cylindrical pipe. RelQtive shifts, resulting for
example ~rom vibrations, can in this mnnner be better isolated and lessened.
Ideally, the conical surface and the opposite surface should anclose an angle
of 10 to 18 .
For the installation of such n pipe, as a first step, the clamp body is
placed in the openin~ of the pipe supporting plate with the conical surface.
The enlar~ement at the rear of the part prevents it from slippin~ out by
itsel~, which is the reason that the work process can if necessary be carried
out separately from the actual installation of the pipes. The automation of
the installation is thus made easier. This is further simplified if a sheet
having formed therein several clamp bodies is used, whereby individual
positioning would be superfluous and entire devices can be fitted ~s
self-contained units into respective openin~s in the pipe supporting plate.
In such a manner, there ~esults an additional protection against corrosion in
cases in which the sheet materisl between the individual devices is continuous
and impermeable to fluids. This enables the use in production oP cheaply
available msterials.
In cases in which an ~djacent chamber is to be formed, a cover m~st be
placed on top of the pipe supporting plate. The sheet material csn ~t the
same time be used to seal the periphery of the cover. The production cost for
an air conditioner in an automobile, for e~ample, can in this way be reduced.
The pipes in question are inserted in the clamp bodies after the lntter
have been loc~ted in the support plate openings. This takes place by means of
a simple pushing motion ~nd readily occurs when the clamp body is bounded on
the inside by a conical surface that features a diameter which becomes
increasingly smaller toward the rear. In this case, a lubricant need not be
employed.
The foregoing also spplies to the fitting of the clamp body in the
openings. In this case, the clamp body has a conical surface on the e~terior,
between the enlargement and the annular membrane. This conicnl surface
connects both parts. The necesssry centr~l loc~tion of the device vis a vis
-- 5 --
.
v
the opening occurs to a great extent automatically. The length of each
annular membranes is ideally two to five times as great as the thickne~s.
In the examples described above, there results an axial securing of both
parts in ~he direction of the application o~ forces ~hich is not alw~ys
sufficient. In a preferred embodiment, therefore, the tensile element
referred to above e~ists to~ether with the tensile element of 8, second
laterally reversed clamp body and the second clamp body lies a&ainst a conical
surface whose arrangement is e~actly similar to that of the first. The first
and second tensile elements and the first and the second clamp bodies in this
case have a common a~is.
The clamp body in the area lying a~ially outside the regiotl of the conical
surface can be designed with at least one encircling bulge, whi.ch prior to the
insertion of the clamp body has a diameter smaller than that of the clamp
body. The inner diameter of the clamp body in this case may, i.n the area
lying radially outside the conical surface, be designed slightly larger than
the exterior diameter of the part to be received. The cross-saction of the
clamp body ther2fore does not need to be enlarged radially during insertion in
this re~ion, which greatly facilitates the insertion of the patt.
During insertion of the part, the bulged areas of the clamp body have
simply to be enlarged outwardly in a radial direction, which however is quite
possible since the bulges in this area do not come in contact ~lith the conical
surfaces in a radial direction and are therefore not constricted by same. In
this respect, they are easily enlarged in a radial direction, c:an easily be
moulded snd after insertisn o~ the part, press against its surf~ce under
elastic initial tension, which at the same time affords good sea~ing.
In order to achieve a good ~ealing result, it is most helpful if the
bulges are themselves fle~ible and pliable and therefore ~ell ~;uited to
ccnfor~ to the sur~ace of the body being accepted. Bulges of corresponding
shape however have only a very slight mechanical re~istance, which can lead to
3Q deformities and particularly to damage, especially on the side facing the part
to be accepted. These effects however can be avoided if the bulge is enlarged
radially by means of a thin walled collar before insertion of the part, if the
part is inserted through the collar and if the casing is then pulled out of
the bulge. The bul~e can thus lie snu61y a6ainst the surface of the inserted
body and can be effective in fulfilling its role.
It must be understood in light of the aforementioned discovery that the
tensile forces introduced from any ~irection into the already installed body
always cause a compression of the clamp body between one or both converging
conical surfaces and the upper aurface of the cylindrical p~Lrt which forms the
opposite surface. The cylindrical part and the conical surfaces consist of a
non-pliable material and the clamp body consists of a non-compressible
material. ~espite the application of such forces, therefore, there can be no
further axial shifting of the accepted part. The initial force required to
achieve this effect is transferred by the bulges lying tightly a~ainat the
surface of the part, to the clamp body. This is very slight and cannot cause
damage to the bulges. The strength of the initial force has no bearing on the
finally `achie~ed fixin~ result, which is insteRd dependent on the angle made
by the conical and opposite surfaces being as small as possible. In this
regard, an angle of between 10 and 35 has proven itself particularly
suitable. The an~le on both sides can vary if forces of varying strengths sre
involved. In relation to its normal use, however, a design which has proven
itself particularly effective has both converging conical surfaces and the
opposite surfaces enclosing identical angles.
The clamp body can consist of any material with soft elastic properties RS
long as these are in and of themselves not compressible. Because it is
especially economical, rubber is preferred, with a Shore A hardness of approx.
55 being advisable.
The bulges can be formed as sealing lips or may alternative~y take the
form of nnnular membranes. In the last case especiQlly, a good sealin~ result
is achieved, which causes the proposed de~ice to be well suited, for example,
to the area of installation.
In snother adv~ntageous design, the clamp body may consist of an elastic,
pliable polymer material; the bulge may have an inner cros*-section that
before insertion is smaller than the sxternal cross-section of the part; and
the bulge of the clamp surface on the side of the clamp bocly is ndjncent the
end of the part.
The insertion of the body to be accepted thus leads melely to a plastic
deformation of the clamp body (which consists of polymer mater~al, preferQbly
of rubber) and not to a permanent change in the ~hape of the received body.
The application of the proposed dasign is very simple. It is limited to
-- 7 --
the simple pushing in of the part to be secured, in Q casin~ already
containine the clamp body. In this csse, a certain amount of moulding is
necessary because the ree cross-section of the bulge remai,ns some~hQt smaller
than the external diameter of the part to be received.
The bulge consists however of the same soft elastic mal;erial as the clamp
body and is freely movable in a radial direction. The forces necessary to
produce the required deformations are thus very slight and relatively large
tolerances in the parts to be connected can be reconciled. As opposed to the
insertion of the cylindrically shaped body described above, its removal from
the casing is not automatically possible.
If an outwardly directed force is applied to the already installed clamp
body, this force is transferred with an elastic initial tension across the
bulge lying against the opposite surface, then to the clamp body. This lies
on the inside against the surface of the cylindrically shal?ed part, and on the
outside against the inner wall of the casing, whose cross section diminishes
outwardly in a wedge-like fashion. The forces introduced into the clamp body
cannot therefore lead to its axial shifting in an outward direction but ~erely
result in a radial compression of the clamp body between tlte conical surface
of the casin~ and the surface of the accepted part. The e~tent of this
compression is dependent upon the angle made by the conica:L surface and the
opposite surface as well as upon the strength of the introduced forces. The
relationships in this case are discussed above. In regard to the securing of
pipes, conical angles of lO to 35 have proven themselves e~cellent,
whereby an angle whose size diminishes toward the projection provides an
improved responsiveness and an angle widening progressivsly in the direction
of the projection provides an improvsd angular movability of the cylindrically
formed part. The rasulting connection may therefore be considered as
unbreakable. In cases in which it might be necessary to have a damage-free
disconnection, this is possible if the part to be received has a circular
boundary and if it is threaded. It can later on be unscre~ed from the clamp
body. In such a design, the pitch of the thread can have a proclivity to
becoming unsealed. This problem is solved by careful desll~n as well as by the
insertion of a sealant that will remain plaatic, for example v~aeline or
grease. Since the joining process doea not require any screwing steps, the
removing of the sealant from the threads does not occur.
The clamp body can, apart from the region of the clQmp surface, be at ~
slight distance from the surface of the body to be accepted, which very much
eases its insertion without ~t the game time endangering the integrity of the
resulting connection. ~or these purposes, the distance does not amount to
more than l to 2 tenths o~ a millimeter.
The shape of the clamp body and the casing must fit that of the body to be
accepted. It can have any shape and can have a polygonal, oval or circular
shape. The bulge can be bounded on the side facing the e!nd of the part by 2
surface ~hich is enlarged in cross-section. In this manner, mechanical damage
to the bulge as well as to the part to be accepted during mutual joining, can
be avoided.
In a further preferred embodiment the bulge on the inner side is bounded
by a surface running parallel to the axis. In thi~ manner, the bulge conPorms
e~ceptionally well to the surface, which is important for ths transfer of
forces introduced across the bul~e to the actual clamp body.
In yet a further preferred embodiment, the bulge is formed by an annular
membrane, which projects in an axial direction from the 1:hickened portion of
the clamp body. The radial thickness of such membrane is quite small and
amounts in general to only a few tenths of a miilimetre. The nxial len6th is
considerably greater, amounting to at least lmm and havin6 nt most a value
matching the diameter of the accepted part. A thin lining is thus
beneficial. In a mechanical sense, it is limited by the resistance capacity
required.
The clamp body consists of an elastically pliable po-Lymer material and is
in this respect easily workable and adaptable. An~ular shifts between the
a~i~ of the accepted body and that of the casing have thus in general no
bearing on the achieved result and can automatically be ;~ccommodnted.
The de~ice is especially well suited for sealing a~ainst liquids and the
mechanically stable securement of pipes as well as the production of pipe
joints. These may in their external form be adapted to designs employed in
the installation field and thereby become an inexpensive replacement for screw
joints commonly employed in this f ield for decades.
This ~ives rise at the same time to the advantage of an essentially
simplified instsllation as well as to good insulstion of body noise caused to
vibration and electricity often carried throu~h pipelines. A possible
_ g _
application is in the theft-proof attachment of automobile license plates.
The circularly bounded part featuring the total surface should however be
designed with a thread, in order to ma~e po~ible remov~l from the trunk of
the automobile. The part features a flat, rotationally symmetrical head that
lies on top of the license plate and an innsr hexagon or slit on the side
facinK the trunk.
In another useful form, the clamp body features an extension from the
narrowest SpQCing between the conical surface and the opposite surface. This
can for example form a cable grommet for the secure and nick-free threading of
cables throu~h the side of an electrical device. Such a cable grommet is ~ery
easily introduced into the opening made in the side of a device, whereby it is
not required that the opening itself be divided. Ergonomically desirable
arrangements are thereby possible. The insertion of the cable grommet in the
opening can, according to the design, originate either from the inside or the
outside.
Following the insertion of the cable grommet into the opening of the
device, the cable can be inserted from without, which is extraordinarily
simple inasmuch as flexible cables assume a certain rigidity in the cable
grommet so that during this step, no problems are caused by nic~ing.
The clamping region of the proposed cable grommet cnn be formed by a bulge
axially juxtaposed to the conical surface, or by a membrane which is thus
situated on the side of the device behind the conical e~tension of the bulge.
The elastic widening of the clamp region by the inserted cable is then
especially facilitated. It may be continued to any desired length and in this
manner enables d simple attachment of the wires to the iappropriate contacts.
The installation process is thereby completed.
If a tensile force is subsequently applied to the free end of the cable, a
direct transfer of forces to the clamp body occurs across the clamping
region. This presses tightly against the conical surface of the device and
thus against a rigid, self-enclosed surface. The cable grommct can thus not
be affected by the tensile forces applied to the csble, but rather undergoes
only a slight deforming under increasing pressure against the axternfll
diameter of the cable. The cable is prevented from giving and it is therefore
beneficial thst the pressurs forces are equally distributed over the entire
area. Severin~ of the ~ires or damage to the insulation is thereby virtually
-- 10 --
impossible.
The resulting securing of a cable in guch a cable grommet is to a large
extent dependent upon the conical angle of the opening ~Ind of the base of the
groove. In general, a better gecurement is achieved as the angle becomes
smaller. At the same time, however, an e~tended axial length must be
accepted, which is not nlways justifiable. Values betw~en 10 and 35
have in general proven themselves advantageous.
The inwardly projecting bulge should if possible be free of sharp-edged
parts, which could lead to cable dama8a and it is therefore useful if the
bulGe ends in a surface extending perpendicular to the cable grommet on the
side f&cing the device.
Internally, the bulge can be bounded by a surface ectending parallel to
the longitudinal axis whereby a particularly simple insertion of the cable can
result, if the bulge is in the form of a membrane and the end of the clamp
body facing the device protrudes in an a~ial direction.
The radial thickness of the membrane need be only a few tenlshs of a
millimeter, insofar as the mechanical fi~ing of the accepted cable is not
primarily based upon the mechanical integrity of the membrane, but rather as
illustrated above, upon the ac1sivation of conical forces in the area of the
conical and opposite surfaces. In this respect the meml)rane and the bulge
merely assume a separation function. For this purpose, a minimal strength is
sufficient. In general, this still lies below the strength required to permit
the damage-free insertion of the cable. Regardine the ]ast point in
particular, it may be necessary and useful in individual cases to slightly
increase the radial thickness of the membrane. The a~ial length does not
normally exceed the diameter of the accepted cable.
The invention will now be described further by way of example only and
with reference to the accompanying drawings, wherein:
Figures 1 through 5 illustrate a preferred embodimerlt of the invention
applied to the sealing of a lid upon a container;
Figures 6 and 7 illustrate the application of the invention to the joining
together of pipes;
Figures 8 through 10 illustrate the application of lshe invention to the
securement of pipes or other parts to a supporting plate;
Figures 11 and 12 illustrate further embodiments of the invention adapted
-- 11 --
to the interconnection of pipes; and
Fi~ure 13 illustrates an application of the invention to its use ~8 a
cable grommet.
Referring now to ~igure 1, there are shown portions of a lid 8 and a
container 9, which are impermeable to liyuids. ~oth are made of plastic.
The lid is provided with an annular eztension which Pits into the openin~
of the eontainer 9 and which is externally bounded by a conical surface 4,
which Bt its upper end has a smaller distance from the eontainer axis than at
the lower end. The eonieal surface 4 defines with the container axis an an~le
of 12 .
The eonical surfsce 4 is bounded at its upper end by an annular shoulder
11. In the angle between the shoulder 11 and the conical surface 4, the
ring-shaped elamp body 2 is located, sueh body eonsistin~ of soft elastie
rubber and having a cireular profile. The dimensions of the clamp body are
sueh that upon insertion of the lid havin~ the elamp body thereon into the
eontainer opening,:elastie deformationlof th~ elamp body profile oeeurs
between the shoulder 11, the conical surfaee 4 and the opposite surfaee S of
the eontainer. A snu~ eonneetion is thereby provided, espeeially between the
eonieal surfaee 4 and the opposite surfaee S.
If at this point an outwardly direeted force is applied to the lid, then
an increasin~ compression of the elamp body 2 results between the conical
surface 4 and the opposite surface S. The degree of mouldability of the elamp
body 2 however, is limited by virtue of the sp0cifie properties of the
material and does not permit Q eross-seetional reduetion of dimension ~.
Removal of the lid from the container is thus not possibLe without damage to
the elamp body and of the eontainer or lid.
The same effect occurs if the container is filled wil:h a medium under high
pressure, which results in an axial pressure upon the licl, leadin~ to an
increased eompression of the elamp body between the conic:al surface 4 and the
opposite surfaee S. ~gain, an unbreakable bond is provicled.
This prineiple applies to the other variations of the design as
illustrated. In Figure 2, for e~ample, the conical 3urfaea 4 is arranged on
the inside of the container, the opposite surface S now being arranged on the
side of the lid e~tension. Further, the profile of the clamp body 2 is
adapted to the shape of the spaee bounded by the oppositel surfaee S and the
- 12 -
.
conical surface 4 and, in addition, the clamp body features on the lower end a
membrane-like annular proJection 12, which lies tightly against the opposite
surfQce 5 under elastic initial tension. This works ~gainst removal of the
lid.
The clamp body 2 is connected with a flange 6 by means of an annular
tensile part 3. This supports the clamp body on ~he stop surface 7, while the
lid is inserted into ~he opening. Then, if an upwardly dirècted force is
e~erted upon the lid, this leads according to the above dQsign to a radial
compression of the clamp body 2 between the conical surface 4 and the opposite
surface 5.
Figure 3 illustrates an embodiment in which the lid is placed over the
container, the latter having a conical lip beariog the conical surface 4. The
clamp body has in this case a prismatic profile and is elastically connected
by the tensile part 3 to the flange 6, which is supported on the container
lip. After th0 joining of lid and container, the cla~p body is deformed in
the manner illustrated and securely holds the lid in place as well as
providing a solid base for the lid. Subsequent opening of the connection,
however, is possible by pulling on the pulling tab 13, which, after Q
temporary elastic defosmation of tensile part 3, causes a movement of the
clamp body do~nwardly in the direction of the widening gap between the conical
surface 4 and the opposite surface 5. The maximum distance between these
surfaces is larger than the radial thickness of the clamp body in an
undeformed state and after reaching this point, the clamp blody is no longer
capable of preventing removal of the lid, which can easily be removed. The
clamp body 2 returns to the illustrated original position after the pulling
tab 13 is loosened.
The design illustrated in Figure 4 is similar in function to that
previously described. In this case however, the opposite surface 5 features
an inwardly turned conical development, which is parallel to the conical
surface 4. The connsction between the lid and the container can again be
broken by employing the pulling tab 13.
~ igure 5 3hows an embodiment similar to that of Figure 1, in which however
the lid extends around the opening of the contalner on the outside.
Accordingly, a conical skirt ha~ing surface 4 depends from the lid surface 11
and is opposed to the cylindrically shaped surface of the container. The
- 13 -
. ~ .
f~
support surface 11 is coextensive with the lid cover portion.
In the pipe connector illustrated in Fi~ure 6 for connectin~ toEether two
pipas or a pipe and sleeve, the characteristic features of Figure 5 are
likewise present. In this case, the inner conical surface 4 of the sleeve or
larger pipe surrounds the opposite ~urface 5 of the inserted pipe, whereby an
undesirable axial shifting of the clamp body 2 (formed by an O-ring) durin~
the insertion of the pipe, is impeded by the surrounding shoulder portion 11
of the external pipe or sleeve.
Pigure 7 shows an application of the invention to the encl-on connection of
sleeveless pipes. The characteristic features of the embodiMent of ~i~ure 5
are again present and are located in opposed relationship to each o~her. The
conical surfaces can bend concavely or conve~ly in an axial dlrection.
Figure 8 shows an application of the invention to the sealed securement of
a pipe in a pipe supporting plate~ The clamp body 2 shown consists of rubber
with a Shore A hardness of 75. It serves the purpose of sealing the space
between pipe supporting plate 9 and pipe 8 subsequently inserted in an opening
in the plate. This may be, for example, a heat exchange pipe of an air
cooler, wherein the heat exchange pipe may have an exterior diameter of 15m~
and be made of copper and the pipe supportin~ plate consist of steel plate and
be 3.5mm thick.
The clamp body is connected by means of the tensile part :I to flange 6,
which lies against the surface of the pipe supporting plate.
In the embodiment of Figure 8, the profile of the rear portion of the
clamp body is thickened conically inside and outside. The smallest internal
diameter is 14.4Dm. The coextensive annular membrane 12 extends coaxially
with the pipe.
The clamp body has an annular outward bulge 13 having a semicircular
profile that extends rearwardly tangentially in a lateral plane and forwardly
tangentially as a conical surface that together with the a~is of the devlce
encloses an angl0 Oe lO . The profile mskes axial contact with an enlar~ed
conical opening in the pipe supporting plate over the rear third of such
opening. A conical surface extends between the bulge 13 and the membrane 12.
This is provided to ease the insertion of the device into the receivlng
opening. Together with the a%is of the device, it encloses a 45 angle.
With an a~ial length of 0.8mm, the membrane 12 has a radial thLckness of
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0.3 mm and the conical gurface 4 encloses togg~her with the Q~iS of the deYice
an angle o 18 .
Figure 9 shows a single and double form of the device of the invention,
having applicstion to a hot w~ter tank. The latter is reproduced in
longitudinal section ~nd consists of hard PVC and Peatures on its upper end
two holes in the casing which on one side enclose the connecting pipes 14 for
the inflow and outelow of water and on the other side the opening for the
insertion of the heating rod 15.
The holes in the casing are circular and bounded by flanges w'nich widen
conically in sn axial direction toward the bottom~ In these hoLes, internally
cylindrically profiled clamp bodies 2 of a non-compressible sofl: rubber are
placed, these making contQct with the conical flanges of the holes.
Each cl~mp body features an annular membrane 12, which lies against the
~ater pipes 14 or against the retainer 16 (see below) under elastic initial
tension. If an out~ardly (i.e., an upwerdly) directed ~ensile force is
applied to the water pipes or to the heating rod retainer, this tensile ~orce
is transferred across the ~embranes 12 to the clamp bodies 2, cQusing the
radial compression of the clamp bodies between the surface of the water pipes
14 or the outer cylindrical susface of the retainer 1~ and the respective
conical inner flange surfaces of the holes in the wall of the container 17.
The pipes 14 and retainer 16! as well as the container, consist of non-pli~ble
materials, while the clamp bodies 2 ~re made of non-compressible material
which is soft and elastic. An axial removal of the pipes 14 or of the
retainer 16 from the holes in the casing of the container is thus not possible.
The retainer 16 is bound on the inside by two converging conical surfaces
4a and the double clamp body 2a is located in the space between the conical
surfaces 4a and the heating rod 15. The clamp body 2a consists of a soft
elastic non-compressible materi~l and an annular membrane 12 extending from
each of the region~ lying axially outside the conical surfeces 4l. The
membrane, bePore insertion of the heating rod 15 features an inner dismeter
smaller than that of the heating rod 15 and the membrane thereby presses
tightly against the surface of the heating rod. If to this ~n ~:~ially or
inwardly directed force i3 applied, this leads each time to a radial
compression of the clamp body 2a a~ainst the conical surfaces 4~ and this
prevents eurther shlfting o~ the heating rod 15.
?
In order to ease the insertion of the heatin~ rod into the forward
membrane 12, an assembly tool is used. This consists of thin-walled aplat
collar, which can shrink to a diameter sli~ltly smaller tha~ the e~istin~
inner diameter of annular membrane 12. Sliding the collar into the membrane
is accordin~ly simple. It i5 ~hen simply spread open, for example with an
awl. It is stable if the ed~es 18 of the collar lying opposite each other in
the re~ion of the split abut and circumferentially support each other. The
awl may be removed and replaced by the heating rod 15, whereby the collar can
easily be pulled out of the elamp body 2, leavin~ the membrane 12 lyin~ snu~ly
against the surface of the heatin~ rod.
In the embodiment shown in Figure 10, a steel plate is deforme~ to provide
a conical flan~e definin~ a circular opening that widens toward the rear of
the platP. The inner surfaces of the conical opening enclose an angle of
20 . Element 8 is located concentrically in the casin~ and is cylindrical
in shape and forms the rear end of a drawhook. Element 8 also consists of
steel and is in this respect just as ri~id as flan~e 9. In the space between
parts ~ and 9, the clamp body 2 is placed. This essentially fills the space
and consists of a rubber elastic material with a Shore A hardness of approx.
55. It can easily be moulded and before insertion of part 8 is easily
positioned in the opening defined by flange 9. As a result, the e%terior
surface of the clamp body abuts the conical surface 4 of the flange 9, which
widens conically towsrd the top, and also the flan~e 6 of the clamp body 2
abuts the surface 7 of the steel plate, the flange 6 projecting radially
outwardly from the cl~mp body.
In the re~ion of the conical surface 4, the inner diameter of the clamp
body 2 is slightly lar~er than the outer diameter of the part 8 to be
flccepted. In the above example, the free space amounts to a tenth of a
millimeter. This facilitates the placement and insertion in the opening of
the clamp body 2 of the part 8 to be accepted.
At its upper end, the inner di~meter of the clamp body i8 r0duced by the
thin annular membrane 12 to a value which is les~ than the outer diameter of
the part 8 to be accepted. The membrane is, by virtue of its small radial
thickness, stretchable and the force required for the complete insertion of
part 8 a~ainst the stretching of the membrane i9 thus relatlvely low. After
insertion of part 8~ membrane 12 clinKs smoothly to its surface and effects a
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:
strong bond therewith.
If a downwardly directed tengile force is applied to the hookt the forces
are immediately applied QCroSS the clamp body 2, which consists of a slightly
pliable, but non-compressible material. The forces pre3sin~ the clamp body
into the conical tapered casing may thus merely lead to its deformation7 as
long as a modicum of free space remains. Once this is occupied, then no
further deformation of the clamp body can occur, irrespective of the softness
of the material employed - i.e., part 8 is fi%ed immovably in an axial
direction. The tensile forces which can be transferred across the drawhook
can thus be of any strength and nre essentially only limited by the mechanical
strength of parts 8 and 9.
Figure 11 illus~rates the application of the invention to the mutual
connection of line~rly abutting pipe ends. The part 9 forms a sleeve, which
consists in this case of PVC and features central and end regions of reduced
cross-section. This aid~ in positioning the pipes inserted into the sleeve 9
and in the centre of the sleeve, an inwardly extendin~ annular projection 19
is provided which serves QS a stop for the pipes.
From opposite ends, the symmetrically circular clamp bodies 2 are pushed
into the sleeve before insertion of the pipes. Each clamp body cons~sts of
soft rubber and has a fl~nge 6 which, after insertion, comes to rest against
the respective end surface of the sleeve and in this manner ensures the proper
location of the clampin~ surfaces in relation to the conical surface of the
casing, which diminishes conicslly in its cross-section toward the end of the
sleeve.
The inner diameter of the clamp body ;s slightly lar~er than the outer
diameter of the pip~e to be inserted. The pipe is thus easily inserted into
the preassembled pipe joint.
In this case as well, each clamp body has a projection for~ed by the
annular membrane 12. The projection juxtaposes with the axial e~tension of
the conical surfsce 9 and the inner di~meter of the membrane ~which is formed
in one piece with the clamp body), is before insertion of the pipe sli~htly
smaller than its outer diemeter.
All that is required for the assembly of the pipe ~oint is that the
already assembled pipe joint i9 pu~hed over the end of each pipe and ~lid
along it until the butt end surface of the pipe comes to r~t against the
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. .
internal flnnular proJection lg of the casing. If following this an outwardly
directed force is applied to the pipe, there results, as in the above
described case, a transfer of the force across the membrane 12 to the
conically tapered clamp body 2, and therewith its radial compression bet~leen
the outer side of the pipe and the conical surface ~ of the casing. Removal
o~ the pipe is thus not possible.
A similar effect occurs if a flowable medium is introduced into the pipe -
for example, pressurized gas or water. Since the frontal sur~ace o~ the pip0
is not sealed to the projection 19, the flowable medium passes into the
annular free space 20. This space lies in front of the clamp body in the
region of its greatest radial ext0nsion. Th0 result is that the pressure of
the medium contained in the pipe leads to a radial compression of the clamp
body 2 betwaen the wall of the pipe and the conical surface 4 of the casing.
This results in good sealing and a good axial securing of the inserted pipe.
Figure 12 illustrate~ an embodiment in which the pipes to be joined are
located at an angle of 90 to ~ach other. The casing surrounding the pipe
ends is similarly angled. The casing features however the sam0 clamp body and
has the same function as described in connection with Fi~,ure 11.
Designs of pipe joints other than those illustrated in Figures 11 and 12
are possible. ~hey include all basic designs required in the sanitation
field, in particular, T-joints, X-joints, angled joints having various angles
and reduction joints for the mutual connection of pipes of differing diameters.
In the examples given in Figures 11 and 12, the spatial position of the
butt end of the inserted pipe in an axial direction is defined by the
projection 19 and in a radial direction by the con~ines of the inner diameter
of the casing. The latter can surround the end of the pipe and be spaced
therefrom by a small distance, which makes it possible to accommodate angular
displacements between the pipes to be connected. The projection 19 can have
one or more cut-outs which permit com~unication between the pipe interior and
the space between the pipe and the casing ~and consequently with the free
space 20) in order to ~scilitate a guick pressure buildup in the free space 20.
In the examples shown in Figures 10 to 12, the clamp body is merely
loosely placed in the cfl~ing. The installation of the clamp body is in thi3
way made particulflrly simple. In certain circumstances on th0 other hand, it
is also possible to adhesively secure the sleeve to the clamp body. In this
way, very strong axially directed ten~ile forces in partlcular are trans~erred
o
more easily to the sleeve. The surfaces bounding the clamp body in an axial
direction generally adapt themselves to the superficial shape of the surfaces
to be secured in relation to each other. Notable surface irregularities are
generally absent, which is why such a clamp body design automatically ensures
the desired result. ~anufacture is accordingly simple and inexpensive.
However, the embodiments described above can have problems in obtaining
good seal if the surPaces to be gecured in relation to each other feature
gross irregularities - which, for example, often occur in concrete or in
poured materials. In order to achieve a good sealing result in these rases,
it has proven helpful to provide the clamp body on the surfaces in question
with a number of axially juxtaposed ribs that extend towart the
circumference. The single ribs have only a short axial extension and are
correspondingly very adaptable. They are thus capable of fitting easily into
the surface irregularities of such material surfaces and can in this mannPr
effect a tight connection. The individual ribs sequenced one after another
complement the effect of the remaining ribs, so that even in this unfavourable
situation, a reliable sealin~ result is achieved in addition to good
securement.
Figure 13 illustrates a example of an application in which the clamp body
body is lengthened into a cable grommet 21. This consists of a hollow body
extended lengthwise, made of soft rubber, which before insertion of the cabl0
is placed lnto the opening, the latter being provided with a conical 1ange
which widens toward the top of the housing 9 of a small alectrical apparatus.
Next, the cable to be accepted is pushed into the opening of the cable
grommet. This i5 relatively simple in that the inner dismeter of the grommet
i5 smaller than the outer diameter of the cable only in the region of the
annular membrane 12 located outside the conical surface 4. The membrane has
very little wall strength and it can easily be widened radially and is freely
movable. After the cable 2 is pushed through the grommet, the membrane
conforms tightly to its surface and provides a strong bond between the cable
and cable grommet. A downwardly directed pull upon the cable leads to a
reciprocal compression of the clamp body against the conical surface 4. Only
the former is pliable~ It therefore dsforms and lies tightly against the
surface of the received cable and further backward mo~ement of the cable is
thus impossible.
The degree of pressure exerted by the clamp body 2 in the re~ion of the
conical surface 4 on the surface of the cable depends on the size of the
conical an~le and the strength of the tensile ~orces applied to the cable.
Both are variable. The represented desiGn shows an angle of 30 , which has
proven itself exceptionally suitable in relation to the equipping of small
electrical devices.
The advantages to be gained with the above cable grommet lie mainly in
easy assembly and in good axial securement of the cable. During tensile
stresses applied to the cable, a good seal results at the point of
introduction.
The employment of auxiliary means to achieve this result is generally not
required. However, such means may further improve the already obtained seal,
especially in situations in which the clampin~ po;nt of the cable ~rommet is
formed by a freely projecting thin, annular membrane. In these cases, there
i5 a possibllity, after insertion of the cable, of applying a bonding a~ent or
glue on at least one point on the exterior. The materials are capable of
easily penetrating the membrane containing polymer material and may in this
manner contribute to an improYement in the connection between the cable sheath
and cable gro~met.
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