U.S. patent application number 11/329881 was filed with the patent office on 2006-07-13 for coupling for joining two pipes.
This patent application is currently assigned to Rasmussen GmbH. Invention is credited to Janos Kertesz, Gerhard Wachter.
Application Number | 20060152005 11/329881 |
Document ID | / |
Family ID | 36250963 |
Filed Date | 2006-07-13 |
United States Patent
Application |
20060152005 |
Kind Code |
A1 |
Kertesz; Janos ; et
al. |
July 13, 2006 |
Coupling for joining two pipes
Abstract
Coupling for joining two pipes, whose end sections, each of
which is provided with a circumferential locking rib, can be
inserted in the coupling, wherein the coupling has at least one
elastic ring that joins at least two elongated webs, and wherein
the coupling has stop projections, which lock in place behind the
locking ribs when the end sections are inserted in the coupling and
can be unlocked to release the connection of the pipes by expanding
at least one of the rings. Each ring is produced separately from
the webs.
Inventors: |
Kertesz; Janos; (Hofheim,
DE) ; Wachter; Gerhard; (Budingen, DE) |
Correspondence
Address: |
Friedrich Kueffner
Suite 910
317 Madison Avenue
New York
NY
10017
US
|
Assignee: |
Rasmussen GmbH
|
Family ID: |
36250963 |
Appl. No.: |
11/329881 |
Filed: |
January 11, 2006 |
Current U.S.
Class: |
285/406 |
Current CPC
Class: |
F16L 37/0985 20130101;
F16L 37/0842 20130101 |
Class at
Publication: |
285/406 |
International
Class: |
F16L 23/00 20060101
F16L023/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 12, 2005 |
DE |
102005001380.5-24 |
Feb 10, 2005 |
DE |
102005006330.6-24 |
Claims
1. A coupling for joining two pipes having end sections, each of
which is provided with a circumferential locking rib and can be
inserted into the coupling, wherein the coupling has at least one
elastic ring that joins at least two elongated webs, and wherein
the coupling has stop projections, which lock in place behind the
locking ribs when the end sections are inserted in the coupling and
can be unlocked to release the connection of the pipes by expanding
at least one of the rings, wherein each ring has been produced
separately from the webs.
2. The coupling in accordance with claim 1, wherein the webs are
flexurally stiff.
3. The coupling in accordance with claim 1, wherein the webs are
provided with stiffening ribs.
4. The coupling in accordance with claim 1, wherein each ring
contains spring steel.
5. The coupling in accordance with claim 1, wherein the coupling is
of metal.
6. The coupling in accordance with claim 1, wherein each ring is a
spring band clip.
7. The coupling in accordance with claim 1, wherein the webs and/or
the sole ring or at least one of the rings contain or contains
plastic.
8. The coupling in accordance with claim 7, wherein the plastic is
reinforced plastic.
9. The coupling in accordance with claim 1, wherein the webs have a
metal core that has been extrusion-coated with plastic.
10. The coupling in accordance with claim 1, wherein when two rings
are used, one of them is connected with one end of each web and the
other is connected with the other end of each web.
11. The coupling in accordance with claim 1, wherein each web has
one groove per ring for holding a ring.
12. The coupling in accordance with claim 9, wherein each end of
the webs has a groove for holding a ring.
13. The coupling in accordance with claim 10, wherein each groove
extends transversely to a longitudinal direction of the webs.
14. The coupling in accordance with claim 13, wherein the depth of
the grooves extends in the longitudinal direction of the webs, and
the width of the grooves corresponds to the thickness of the
rings.
15. The coupling in accordance with claim 14, wherein the rings
have been formed from strips secured in at least one of the
grooves.
16. The coupling in accordance with claim 15, wherein the ends of
the strips have been joined by positive locking.
17. The coupling in accordance with claim 11, wherein and each ring
is secured in at least one groove of the webs by an interference
fit, snap fit, positive locking, or material bonding.
18. The coupling in accordance with claim 1, wherein each ring has
been produced as a closed ring by injection molding.
19. The coupling in accordance with claim 1, wherein each ring is
corrugated.
20. The coupling in accordance with claim 1, wherein the rings are
joined by elongated parts that are secured in longitudinal grooves
of the webs by a snap fit.
21. The coupling in accordance with claim 1, wherein the webs are
comprised of thermoplastic material, and each ring has been
extrusion-coated by the material of the webs.
22. The coupling in accordance with claim 1, wherein when two webs
are used, the webs are joined by a joint.
23. The coupling in accordance with claim 22, wherein the joint is
a film joint or hinge.
24. The coupling in accordance with claim 6, wherein if the rings
are designed as spring band clips secured on or near the ends of
the webs, the spreading jaws of one of the spring band clips are
displaced by 180.degree. in the circumferential direction of the
coupling relative to the spreading jaws of the other spring band
clip.
25. The coupling in accordance with claim 1, wherein each web has
been formed from a sheet-metal part by punching and bending.
26. The coupling in accordance with claim 4, wherein each ring has
a break and a joint on the diametrically opposite side from the
break, wherein the webs are of plastic, and each ring is held in
the plastic of the webs except for the break and the joint.
27. The coupling in accordance with claim 26, wherein the joint is
an elastically flexible part of the ring.
28. The coupling in accordance with claim 27, wherein the joint
forms a rim that projects outwardly from the ring.
29. The coupling in accordance with claim 26, wherein each ring has
been extrusion-coated with the plastic of the webs.
30. The coupling in accordance with claim 26, wherein the webs have
radially outwardly projecting knobs on both sides of the break.
31. The coupling in accordance with claim 26, wherein a ring is
provided close to or at each end of the web, and the break in one
ring is arranged with a displacement of 180.degree. relative to the
break in the other ring in the circumferential direction of the
rings.
32. The coupling in accordance with claim 26, wherein the webs are
held together by a connecting device, which releasably bridges the
ring break or each ring break.
33. The coupling for joining two pipes having end sections, each of
which is provided with a circumferential locking rib, and which can
be inserted into the coupling, wherein the coupling has at least
two elastic ring segments that join at least two elongated webs,
and wherein the coupling has stop projections locked in place
behind the locking ribs when the end sections have been inserted in
the coupling and can be unlocked to release the connection of the
pipes by deforming at least one of the ring segments, wherein each
ring segment has been produced separately from the webs.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a coupling for joining two
pipes, whose end sections, each of which is provided with a
circumferential locking rib, can be inserted into the coupling,
wherein the coupling has at least one elastic ring that joins at
least two elongated webs, and wherein the coupling has stop
projections, which lock in place behind the locking ribs when the
end sections are inserted in the coupling and can be unlocked to
release the connection of the pipes by expanding at least one of
the rings.
[0003] 2. Description of the Related Art
[0004] A coupling of this type is known from EP 1 378 701 A1. It is
produced as a one-piece injection-molded plastic part. However, if
a very hot fluid is to be conducted through the pipes that are to
be joined, it is possible that at least those parts of the coupling
that come into direct contact with the pipes will not be able to
withstand the high temperatures of the fluid or the pipes. The same
problem can occur in the vicinity of a very hot object, e.g., the
engine or exhaust system of a motor vehicle. Moreover, the webs are
designed as spring arms. Therefore, the coupling is unable to
withstand strong forces that act to bend the pipes relative to each
other, so that the joint would become loose.
SUMMARY OF THE INVENTION
[0005] It is the primary object of the invention to provide a
coupling of the aforementioned type which can be produced at least
partly from material that is more heat-resistant and can withstand
larger mechanical loads.
[0006] In accordance with the invention, this objective is achieved
by the fact that each ring has been produced separately from the
webs.
[0007] With this type of construction, the materials for the
individual parts can be more or less freely selected.
[0008] For example, it is possible for the webs to be flexurally
stiff, for example, by the use of suitably stiff material,
particularly metal.
[0009] Furthermore, the webs can be provided with stiffening ribs,
especially ones which extend in the longitudinal direction of the
webs.
[0010] In addition, more than two webs can be provided, for
example, three or four webs that are uniformly distributed over the
circumference of the ring or rings or two webs on one side of the
coupling and two webs on the other side.
[0011] The coupling can consist exclusively of metal.
[0012] In this regard, at least the sole ring or each ring can
contain spring steel.
[0013] It is especially advantageous if each ring is designed as a
spring band clip. A spring band clip can be expanded against its
spring tension in a conventional way to release the coupling from
at least one of the pipes, especially if the spring band clip is
fastened at one end or near one end of the webs, and thus to
release the connection of the pipes. If only one spring band clip
is used as the only ring, it can also be fastened in the middle of
the length of the webs. In this case, the coupling can also be
released from both pipes at the same time by means of the spring
band clip.
[0014] Alternatively, it is possible for the webs and/or the one
ring or at least one of the rings to contain plastic, especially
reinforced plastic.
[0015] In addition, the rings can also be constructed
conventionally as closed circular rings with a greater diameter
than the pipes, or they can be oval in shape. If they are oval, the
stop projections should be located within those regions of the
rings whose radius of curvature is the greatest. The rings can then
be radially expanded in the regions that have the stop projections
by radial compression of the regions of the rings between the stop
projections in order to unlock the stop projections behind one or
both of the locking ribs and release the connection of the pipes by
the coupling.
[0016] Furthermore, the webs can have a metal core that is
extrusion-coated with plastic.
[0017] When two rings are used, one of them can have been connected
with one end of each web and the other can have been connected with
the other end of each web.
[0018] In addition, each web can have one groove per ring for
holding the ring.
[0019] In this regard, each end of the webs can have a groove for
receiving a ring.
[0020] Each groove can extend transversely to the longitudinal
direction of the webs, while the depth of the grooves extends in
the longitudinal direction of the webs, and the width of the
grooves corresponds to the thickness of the rings.
[0021] The rings can have been formed from strips, which have been
secured in at least one of the grooves. In this regard, the ends of
the strips can have been joined by positive locking, and each ring
can have been secured in at least one groove of the webs by an
interference fit, snap fit, positive locking, or material
bonding.
[0022] Preferably, each ring is corrugated.
[0023] Alternatively, each ring can have been produced as a closed
ring by injection molding. This eliminates their production from
strips, bending them together in the shape of a ring, and joining
the ends of the strips.
[0024] Another possibility consists in having joined the rings by
elongated parts that have been secured in longitudinal. grooves of
the webs by a snap fit. This has the advantage that in the case of
relatively small diameters of the pipes, the rings can remain
unchanged, and only the radii of curvature of the webs and their
stop projections would have to be reduced accordingly.
[0025] In addition, the webs can consist of thermoplastic material,
in which case each ring has been extrusion-coated by the material
of the webs. This eliminates the need for separate assembly of the
rings and webs. Nevertheless, they can be produced from different
materials. If the rings have been made of metal, they are
simultaneously protected against corrosion by the plastic that
surrounds them.
[0026] When two webs are used, the webs can have been joined by a
joint, especially a film joint or hinge. The webs then always
remain joined, which is advantageous especially with respect to
their storage, transport, or assembly.
[0027] If the rings are designed as spring band clips on or near
the ends of the webs, the spreading jaws of one of the spring band
clips should be displaced by 180.degree. in the circumferential
direction of the coupling relative to those of the other spring
band clip. With this arrangement, it is possible to move the webs
uniformly over the circumference of the coupling in the radial
direction towards the outside during the expansion of the spring
band clips by spreading their spreading jaws in order to release
the coupling from the pipes.
[0028] Furthermore, each web can have been alternatively produced
from a sheet-metal part by punching and bending.
[0029] In another embodiment, when the ring or each ring is made of
spring steel, each ring has a break and a joint on the
diametrically opposite side from the break, the webs consist of
plastic, and each ring is held in the plastic of the webs except
for the break and the joint. In this regard, each web extends over
almost half the circumference of the ring, more or less in the form
of one half of a hollow cylinder cut in two axially. Therefore, the
webs are very flexurally stiff about an axis that extends
transversely to their axial length. Due to the break(s) and the
joint(s), the webs, including the ring or rings, can be spread
approximately radially to the pipes in a simple way by inserting a
spreading tool, e.g., spreading pliers, into the gap or slit formed
by the break in order to disengage the stop projections from the
locking ribs of the pipes and open the coupling, so that at least
one of the coupled pipes can be pulled out of the coupling to
separate the pipes when desired.
[0030] In this embodiment, the joint can be an elastically flexible
part of the ring. This part of the ring is thus an integral,
one-piece part of each ring. Therefore, the joint is formed at the
same time that the ring is produced.
[0031] The joint forms a bulge that projects outwardly from the
ring. Due to this shape of the joint, when the coupling is opened,
the webs and thus their stop projections are moved outward more or
less the same distance in the radial direction of the pipes and
disengage from the locking ribs of the pipes without a large
spreading movement of the ring or rings. This is an advantage, for
example, in the case of very small pipe diameters and
correspondingly small ring diameters.
[0032] In addition, each ring can have been extrusion-coated with
the plastic of the webs. This saves separate assembly of the parts
of the coupling. At the same time, the plastic provides corrosion
protection for the ring or rings.
[0033] To facilitate the opening of the coupling when the break in
the ring leaves only a very small gap that would make it difficult
to insert a spreading tool, the webs can have radially outwardly
projecting knobs on both sides of the break. The spreading tool can
then be easily inserted between these knobs. The knobs can be
formed in a very simple way at the same time as the web injection
process.
[0034] In this embodiment as well, provision is preferably made to
provide a ring close to or at each end of the web and to arrange
the break in one ring with a displacement of 180.degree. relative
to the break in the other ring in the circumferential direction of
the rings. This arrangement of the breaks in the rings also assists
in allowing the webs to be uniformly lifted from the pipes in the
radial direction over their circumference until their stop
projections no longer engage the locking ribs of the pipes, so that
the pipes can be separated.
[0035] In addition, the webs can be held together by a connecting
device, which releasably bridges the ring break or each ring break.
This connecting device increases protection against spreading of
the rings under high bending forces exerted on the coupling. At the
same time, it serves as an assembly indicator, which makes it
evident whether the connection of the pipes by the coupling has
been carried out correctly.
[0036] EP 1 378 701 A1 also discloses a coupling for joining two
pipes, whose end sections, each of which is provided with a
circumferential locking rib, can be inserted in the coupling,
wherein the coupling has at least two elastic ring segments that
join at least two elongated webs, and wherein the coupling has stop
projections, which lock in place behind the locking ribs when the
end sections are inserted in the coupling and can be unlocked to
release the connection of the pipes by deforming at least one of
the ring segments.
[0037] With respect to this disclosure, a second objective of the
invention is likewise to specify a coupling which can be produced
at least partly from material that is more heat-resistant and can
withstand larger mechanical loads.
[0038] In accordance with the invention, this second objective is
likewise achieved by the fact that each ring segment has been
produced separately from the webs.
[0039] The various features of novelty, which characterize the
invention, are pointed out with particularity in the claims annexed
to and forming part of the disclosure. For a better understanding
of the invention, its operating advantages, and specific objects
attained by its use, reference should be had to the drawing and
descriptive matter in which there are illustrated and described
preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWING
[0040] In the drawing:
[0041] FIG. 1 shows an axial section through a connection of two
pipes by means of a first embodiment of a coupling of the
invention.
[0042] FIG. 2 is the same axial section through the pipes to be
connected as in FIG. 1 but without the coupling;
[0043] FIG. 3 is a perspective view of the coupling of FIG. 1;
[0044] FIG. 4 is an axial view of the coupling of FIG. 1;
[0045] FIG. 5 is a front elevation of a web of the coupling of FIG.
1;
[0046] FIG. 6 is a side view of the web of FIG. 5;
[0047] FIG. 7 is an axial view of a ring of the coupling of FIG.
1;
[0048] FIG. 8 is an enlarged view of the section X of the view of
the ring of FIG. 7;
[0049] FIG. 9 shows a side view of the ring of FIG. 7;
[0050] FIG. 10 is a side view of a somewhat modified web of the
coupling of FIG. 1;
[0051] FIG. 11 shows another modification of a web of the coupling
of FIG. 1 in longitudinal section;
[0052] FIG. 12 shows an embodiment of a ring of the coupling of
FIG. 1 that is somewhat modified relative to FIGS. 7 to 9 in the
non-bent (flat) state before closure of the ring;
[0053] FIG. 13 shows another modification of a ring of the coupling
of FIG. 1 in the non-bent state before closure of the ring;
[0054] FIG. 14 is a perspective exploded view of a second
embodiment of a coupling of the invention with two webs and a
spring band clip;
[0055] FIG. 15 is an axial view of a third-embodiment of the
invention, in which the shape of the ring is modified relative to
the embodiment of FIG. 1;
[0056] FIG. 16 is a side view of a fourth embodiment of the
invention;
[0057] FIG. 17 is an axial view of the embodiment of FIG. 16;
[0058] FIG. 18 shows an enlarged section of the coupling of FIGS.
16 and 17 with a modified embodiment of a joint of the coupling of
FIGS. 16 and 17;
[0059] FIGS. 19 shows an embodiment that is modified in such a way
relative to the fourth embodiment that two narrower rings are
provided instead of one broad ring made of spring steel;
[0060] FIG. 20 shows an axial view of a part of a fifth embodiment
of a coupling of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0061] FIG. 1 and FIGS. 3 to 9 show a specific embodiment of the
coupling of the invention and its individual parts. The coupling is
used to join two pipes 1 and 2, which are made of a thermoplastic
material or metal and are only partially shown in the drawings.
Pipes 1 and 2 are shown in FIG. 2 without the coupling. The end
sections 3 and 4 of the pipes 1 and 2 are inserted in the coupling
and fitted together. The regions of the end sections 3 and 4 that
are fitted together are sealed from each other by a gasket 5. The
end section 4 is welded to the remaining part 6 of the pipe 2. Each
end section 3 and 4 has a circumferential locking rib 7 and 8,
respectively.
[0062] The coupling has radially inwardly projecting stop
projections 10 at the ends of axial, flexurally stiff webs 9. The
stop projections lock or snap in behind the locking ribs 7 and 8
when the end sections 7 and 8 are inserted in the coupling, and at
the same time they fit together. For this purpose, the webs 9 are
joined at their ends by elastic rings 11, and the locking ribs 7, 8
and the stop projections 10 are provided with inclined surfaces.
Therefore, when the pipes 1, 2 are connected, the stop projections
10 slide over the locking ribs 7, 8, accompanied by elastic
expansion of the rings 11, until the stop projections 10 snap in
behind the locking ribs 7, 8.
[0063] To be able to release the connection of the pipes 1, 2, the
rings 11 have a slightly oval or elliptical shape (see FIGS. 4 and
7), and the webs are joined with the rings 11 in the areas that lie
between the areas with the smaller radius of curvature.
Alternatively, the rings 11 can also be circular, with their
diameter being greater than the inside diameter of the stop
projections 10. Radial compression of the areas between the webs 9
causes the areas of the rings 11 that are connected with the webs 9
to be forced apart to such an extent that the inner edges of the
stop projections 10 are forced radially outward beyond the
circumference of the locking ribs 7, 8, after which the pipes 1, 2
can be separated. However, it is also possible to expand only one
ring 11 in the areas connected with the webs 9 by radial
compression of the ring areas between the webs 9 to separate the
pipes 1, 2.
[0064] The webs 9 and rings 11 are separately produced and then
connected with each other. Therefore, the rings can be individually
produced in different shapes and from different materials.
[0065] In the specific embodiment shown in FIG. 1 and FIGS. 3 to 9,
the rings 11 are produced from flat strips, whose ends are joined,
e.g., by welding. To join the rings 11 with the webs 9, each end of
the webs 9 is provided with a groove 12. The grooves 12 extend
essentially transversely to the webs 9. The depth of the grooves 12
extends in the longitudinal direction of the webs 9, and the width
of the grooves 12 corresponds to the thickness of the rings 11. The
rings 11 are inserted with axially narrower regions 13 (see
especially FIG. 9) in the grooves 12 and secured therein. The
narrower regions 13 are somewhat bent, as are the grooves 12 that
receive them (see FIGS. 4, 5, and 7). The bending as well as the
steps 14 at the transitions from the narrower regions 13 to the
broader regions of the rings 11 that lie between them prevent a
relative rotation of the rings 11 and grooves 12 in the
circumferential direction of the rings, to which prevention the
steps 14 that rest against the side of the webs 9 next to the base
of the groove also contribute. In addition, the narrower regions 13
are bounded by projecting rims 15, of which the rim 15 in section X
is shown enlarged in FIG. 8. These rims 15 also assist in
preventing the webs 9 and rings 11 from rotation relative to each
other in the circumferential direction of the rings 11.
[0066] In addition, the webs 9 are provided with stiffening ribs
16, which extend parallel to one another on the outside of the webs
9 in the longitudinal direction of the webs 9. Seven stiffening
ribs 16 are shown in the drawings. However, the number of
stiffening ribs 16 depends on the width of the webs 9 and the width
of the stiffening ribs 16 and on the required stiffness of the webs
9.
[0067] All parts of the coupling can be made of metal. The rings 11
preferably consist of spring steel but can also be made of
elastically flexible plastic. Furthermore, it is possible for one
of the rings 11 to be made of metal and the other of plastic. The
webs 9 can also be made of plastic. The plastic of both the webs 9
and the rings 11 can be reinforced, for example, with glass fibers,
carbon fibers, glass beads, or particles of minerals. However, the
webs 9 can also have a metal core extrusion-coated with a
plastic.
[0068] The rings 11 can be secured in the grooves 12 in a variety
of ways. For example, it is possible to secure them in the grooves
12 by an interference fit or by material bonding, for example, by
welding or adhesive bonding. It is also possible to secure them in
the grooves 12 by positive locking. An example of a
positive-locking connection is shown in FIG. 10, in which the
grooves 12 are provided with elastically yielding stop projections
17 on the inside of one of their edges that extends transversely to
the longitudinal direction of the web 9. When the rings 11 are
inserted into the grooves 12, the stop projections 17 yield and
lock into place behind the rings 11, which are inserted as far as
the base of the groove. In this case, the webs 9 would consist of
some elastic plastic or of a metal core extrusion-coated with some
elastic plastic.
[0069] However, as shown in FIG. 11, it is also possible to form
tapped holes 18 in the webs 9 transversely to the grooves 12. The
tapped holes 18 extend at least as far as the grooves 12 or, as
shown in FIG. 11, beyond the grooves 12. Screws can be screwed
through these tapped holes 18 and through corresponding holes 19
(see FIGS. 12 and 13).in the rings 11. In addition, the stop
projections 17 can also be provided here. This enables the coupling
to withstand very high axial tensile forces exerted on the coupling
by the pipes 1, 2.
[0070] The rings 11 can be designed as closed rings in the first
place. However, they can also be designed as initially flat strips,
which are then bent around more or less circularly and joined at
their ends. For example, the ends can then be welded or joined by
positive locking. Thus, as shown in FIG. 12, a positive-locking
connection of the ends of the strips 11a can be produced by forming
one end as a hook 20, preferably a right-angled hook, and by
providing the other end with an undercut 21 that matches the shape
of the hook 20. The hook 20 is then hooked into the undercut 21
after or during the bending of the strip 11a into a circular shape.
During the assembly of the rings 11 and webs 9, the joint can then
be laid in one of the grooves 12 according to FIG. 11 and
additionally secured by two screws, each of which is screwed
through one of two tapped holes 18, which pass through the
corresponding grooves 12, and through one of the holes 19, which
are placed near the ends of the strip 11a.
[0071] Alternatively, the strip 11a shown in FIG. 13 can be
provided at one of its ends with a wedge-shaped tip 22 and at its
other end with a wedge-shaped slot 23 that matches the shape of the
tip 22. When the strip 11a is bent around, the tip 22 fits into the
slot 23. The joint can then be inserted in a groove 12 of the web
9, as shown in FIG. 11, and secured by two screws that pass through
the tapped holes 18 and holes 19.
[0072] FIG. 14 shows an embodiment of a coupling of the invention
in an exploded view, in which two opposite webs 9 are joined on
their radially inner side by a ring in the form of a spring band
clip 24, which is made of spring steel. The spring band clip 24 is
fitted onto the radially inner sides of the webs in grooves 25 that
run transversely to the webs and is secured therein, for example,
by adhesive and/or screws or by means of a snap fit. In the
illustrated embodiment, the spring band clip is secured in the
grooves 25 by adhesive bonding.
[0073] The spring band clip 24 is a conventional hose band clip,
which tightens by its own spring tension around a hose that is to
be clamped on a pipe or pipe fitting and can be released again by
expansion by means of suitable pliers applied at their radial
spreading jaws 26 and 27. This causes the diameter of the spring
band clip 24 to increase until a projection 28 of one spreading jaw
26 stops against the other spreading jaw 27.
[0074] In this design of the coupling, if the end sections 3 and 4
of the pipes 1 and 2 are inserted and fitted together in the
coupling, the spring band clip 24 fastened to the webs 9 is
expanded against its spring tension until the stop projections 10
lock in place behind the locking ribs 7, 8. To release the coupling
and separate the pipes 1, 2, the spring band clip 24 is expanded
manually or by means of pliers until the inside edges of the stop
projections 10 lie on a larger circular arc than the outer edges of
the locking ribs 7, 8.
[0075] Alternatively, the spring band clip 24 can be secured on the
outer circumference of the webs 9; for example, it can likewise be
fastened by adhesive in a transverse groove or secured by a snap
fit or by means of screws.
[0076] In addition, instead of the illustrated spring band clip 24,
a different clip can be used, for example, a tensible hose band
clip, which expands when opened, e.g., a so-called worm drive hose
clip.
[0077] In addition, with suitable design of the grooves 12, it is
possible to fasten a spring band clip 24 in each groove 12.
[0078] The rings 11 can be connected by elongated narrow parts,
which are fastened in longitudinal grooves of the webs 9 by a snap
fit. In the case of still smaller diameters of the pipes, the rings
11 can then remain unchanged. Only the radii of curvature of the
webs 9 and their stop projections 10 would have to be reduced
accordingly.
[0079] If the webs 9 are made of thermoplastic plastic and each
ring 11 is extrusion-coated with the material of the webs 9, a
subsequent assembly of the webs and rings 11, 24 can be dispensed
with. However, the webs 9 and rings 11, 24 can be made of different
materials. If the rings 11, 24 are made of metal, the webs, if they
surround the material of the rings 11, 24, simultaneously provide
corrosion protection for the rings 11, 24.
[0080] In addition, in the case of two webs 9, the webs 9 can be
joined by a joint (not shown), especially a film joint or hinge.
The webs 9 then always remain joined, which simplifies especially
their assembly, transport, or storage.
[0081] If the rings are designed as spring band clips 24 on or near
the ends of the webs 9, the spreading jaws 26, 27 of one of the
spring band clips 24 should be displaced by 180.degree. in the
circumferential direction of the coupling relative to those of the
other spring band clip 24. This makes it possible to move the webs
uniformly over the entire circumference of the coupling in the
radial direction towards the outside during the expansion of the
spring band clips if the webs 9 are designed suitably long.
Furthermore, the spreading jaws 26, 27 of one of the spring band
clips 24 can be compressed with one hand, and the spreading jaws of
the other spring band clip 24 can be compressed with the other
hand, whether this is done by direct manual manipulation or by
means of pliers, in order to spread or expand the spring band
clips. This facilitates the operation of the spring band clips,
especially if they have a large spring tension, in order to open
the coupling.
[0082] FIG. 15 shows an axial view of an embodiment of the coupling
of the invention, in which the rings 11 are likewise made of a
spring band, which, however, is corrugated. The corrugated form can
be more or less rectangular, as shown in the drawing.
Alternatively, the corrugated form can have modified half-waves,
for example, semicircular half-waves. Furthermore, the corrugated
form does not have to be periodic. Depending on the circumference
of the rings 11, the width of the webs 9, and the width of the
half-waves, three or more webs 9 can be provided instead of only
two webs 9 in each case. In this regard, the webs 9 can be arranged
with a uniform distribution over the circumference of the rings 11,
which also applies to the uncorrugated rings 11 or clips. At the
same time, the corrugations can help prevent a displacement of the
webs 9 in the circumferential direction of the rings 11.
[0083] Instead of the spring band clip 24 made of a flat band or
strip, as shown in FIG. 14, a spring band clip with a corrugated
band or strip can also be used.
[0084] In addition, the webs in a form similar to that of the webs
9 can be produced from a sheet-metal part by punching and
bending.
[0085] In the embodiment of the coupling of the invention according
to FIGS. 16 and 17, the coupling comprises a ring 11 and two webs
9. In this embodiment, the width of the ring 11 is almost the same
as the axial length of the webs 9. The ring 11 is likewise produced
from a spring steel band. However, it has a narrow break
(interruption) 29, i.e., a slit or gap that runs all the way
through axially. However, the break 29 could also be wider. The
ring 11 would then be shaped somewhat like a C. Basically, it would
only be necessary that it extend more than 180.degree. in the
circumferential direction.
[0086] The webs 9 again consist of plastic, with which half of each
ring 11 is extrusion-coated. The ring 11 is secured in the webs 9
in this way. The extrusion coating of the ring saves separate
assembly of the parts of the coupling. At the same time, the
plastic provides the ring with corrosion protection.
[0087] The webs 9 extend on one side close to the , break 29 in the
ring 11 and on the other side close to a joint 30, which is formed
as a single piece with the ring 11 on the diametrically opposite
side from the break 29 and results from the flexural elasticity of
the spring steel band that forms the ring 11 between the webs 9.
Since the webs 9 extend almost 180.degree. along the circumference
of the coupling or the ring 11 and, in addition, are reinforced by
the broad ring 11, they are very flexurally stiff transversely to
their axial longitudinal direction, especially about a transverse
axis that runs through the break 29 and the joint 30. Therefore,
the stiffening ribs 16 of the previously described embodiments can
be eliminated. However, the webs 9 are provided with stop
projections 10 as in the preceding embodiments.
[0088] To remove at least one of the pipes 1, 2 (FIGS. 1 and 2)
from the coupling to the right or left, as shown in FIG. 16, for
the purpose of breaking the connection of the pipes, it is only
necessary to insert a spreading tool, e.g., simple spreading
pliers, into the break 29 and then to operate it, so that the ring
11 is turned about the joint 30, and thus the webs 9 and their stop
projections 10 are also moved radially apart until the stop
projections 10 no longer engage the locking ribs 7, 8 (FIGS. 1 and
2).
[0089] To design the break 29 as narrow as possible, recesses 31,
into which the spreading arms of spreading pliers fit, can be
formed in the ends of the ring 11. Alternatively or additionally,
radially outwardly projecting knobs 32 can be formed on the webs 9
in the vicinity of the break 29, and the spreading pliers or other
spreading tool can be applied on these knobs 32.
[0090] In the modification of the embodiment of FIGS. 16 and 17
that is illustrated as an enlarged section in FIG. 18, the joint 33
of the ring 11 is a bulge that projects outwardly from the ring 11
between the webs 9 opposite the break 29. It is shown here as a
more or less omega-shaped bulge, but it could also be C-shaped. Due
to this shape of the joint 33, when the coupling is opened, the
webs 9 and thus their stop projections 10 are moved more or less
the same distance in the radial direction of the pipes and
disengage from the locking ribs 7, 8 of the pipes 1, 2 without a
large spreading movement of the ring 11. This is advantageous
especially in the case of very small pipe diameters and
correspondingly small ring diameters.
[0091] In the embodiment shown in FIG. 19, instead of the one broad
ring 11 shown in FIGS. 16 and 17, two narrower rings 11 are
provided. They are embedded in or extrusion-coated by the plastic
of the webs 9 close to or at each axial end of the webs. In this
regard, the break 29 in one of the rings 11 is displaced
180.degree. relative to the break in the other ring in the
circumferential direction of the rings 11. This arrangement of the
breaks 29 in the rings 11 also assists in allowing the webs 9 to be
uniformly lifted from the pipes 1, 2 in the radial direction over
their circumference until their stop projections 10 no longer
engage the locking ribs 7, 8 of the pipes 1, 2, so that the pipes
1, 2 can be separated. In this regard, it is also possible to
spread only one of the rings 11 to disengage only one of the pipes
1, 2.
[0092] In the embodiment according to FIGS. 16 to 19, each of the
webs 9 can be provided in its axial center with a radially inwardly
projecting stop rib to limit the distance the pipe ends can be
pushed into the coupling and to ensure axial centering of the pipe
ends in the coupling.
[0093] In addition, the webs can be held together by a connecting
device (not shown), which releasably bridges the ring break or each
ring break. The connecting device can have a ring, preferably an
oval or elongated ring, which can lock into place in undercuts of
projections, for example, the knobs, on the webs on both sides of
the break(s), or it can have projections of this type on the webs,
which bridge the break(s) with axial hooks and are formed on or
fastened to at least one of the projections formed on one side of
the break and can be hooked onto or locked in place behind a
projection that is formed on the other side of the break. Instead
of the hooks, it is also possible for only axial extensions on at
least one of the projections, which is provided on a web or on the
web on one side of the break(s), to extend as far as an opposing
projection, which is provided on the other side of the break(s),
and to be releasably fastened to this opposing projection by a
bolt, which passes through holes in the extensions and in the
opposing projection.
[0094] This connecting device offers additional protection against
spreading of the rings under high bending forces exerted on the
coupling, for example, in a traffic accident of a motor vehicle in
which pipes are joined by the coupling. If, on the other hand, the
coupling is to be opened to separate the pipes, the connection of
the webs produced by the connecting device can be released in
advance. At the same time, the connecting device serves as an
assembly indicator, for if the webs have been connected by the
connecting device, this indicates that the connection of the pipes
has been carried out correctly, since the connection of the webs by
the connecting device is possible only if the pipes have first been
correctly joined by the coupling.
[0095] The embodiment of the coupling of the invention that is
shown in FIG. 20 differs from the embodiment shown in FIG. 1 first
by virtue of the fact that the webs 9 are not provided with grooves
12 that pass all the way through in the circumferential direction
of the coupling but rather with undercut grooves 12a, 12b that
extend only partially into the webs 9 in the circumferential
direction of the coupling at each axial end of the webs 9. Second,
the embodiment of FIG. 20 differs from that of FIG. 1 by virtue of
the fact that the webs 9 are not connected by one-part rings, such
as the rings 11, but rather are connected at each of their axial
ends by ring segments 11a, i.e., a total of four elastically
flexible segments made of plastic or spring steel, of which only
one is shown in FIG. 20. The ring segments 11a are strip-shaped,
and their ends are formed to conform to the grooves 12a, 12b, so
that the ends of the ring segments 11a can fit into the respective
grooves 12a, 12b, in which they are held by frictional engagement
in the axial direction and by positive locking in the
circumferential direction. The application of radial pressure on
the ring segments 11a from the outside lifts the webs 9 radially
from the pipes 1, 2 to disengage their stop projections from the
locking ribs 7, 8 of the pipes 1, 2 and thus to separate the
pipes.
[0096] Alternatively, instead of the grooves 12a, 12b that are
axially closed at one end, it is possible to form axially
continuous grooves with the same cross-sectional shape as that of
the grooves 12a, 12b in the sides of the webs 9 and to design the
ring segments 11a sufficiently wide that they, like the ring 11 in
FIG. 16, extend at least over almost the entire length of the webs
9. In this case, only two ring segments all together would be
necessary.
[0097] Another alternative consists in providing several webs 9
that are narrower in the circumferential direction of the coupling
and are uniformly distributed over the circumference of the
coupling. These webs 9 are each connected by ring segments that are
narrower in the circumferential direction of the coupling but
otherwise have the same form and are made of the same material as
the ring segments 11a. Therefore, depending on the size of the
diameter of the pipes 1, 2, the diameter of the coupling can be
adapted to the diameter of the pipe, by using a suitable number of
webs and ring segments.
[0098] While specific embodiments of the invention have been shown
and described in detail to illustrate the inventive principles, it
will be understood that the invention may be embodied otherwise
without departing from such principles.
* * * * *