[0001] The invention relates to an adapter for use in pipes or tubes of gas devices, particularly
gas discharge pipes, particularly in combination with combustion air supply pipes,
that concentrically engage about the gas discharge pipes in order to form an annular
air channel therewith.
[0002] Such adapters are used to couple supply pipes and discharge pipes of gas devices
to the pipes to and from a discharge structure. The location of the adapter may in
principle be anywhere between the gas device and the discharge structure in horizontal
or vertical pipe portions. The adapter will often be arranged near the gas device,
connecting to the supply and discharge passages provided in said gas device.
[0003] Such adapters may also be formed for forming a transition between pipes of different
diameters. For instance the supply and discharge passages at the boiler side may have
a diameter of 60 mm and 100 mm, respectively, and the pipes to the discharge structure
a diameter of 80 mm and 125 mm, respectively.
[0004] Adapters may furthermore be provided with a condensation interception and condensation
drain for condensation that flows along the inner surface of the gas discharge pipe
and may not end up in the boiler.
[0005] Known adapters have an inner pipe adapter including condensation interception and
condensation drain, to which a connection pipe is integrally formed that axially protrudes
a length from an outer pipe adapter, which has the shape of a casing. The condensation
interception is an annular channel to which a radially extending drain pipe has been
connected, which extends through a hole in the casing and to which a further pipe
or tube can be connected. There are at least to embodiments, with connection pipes
that are provided with a connection end for accommodation of the gas discharge pipe
at the boiler side and with a connection end for accommodation by the gas discharge
pipe at the boiler side, respectively. Which one is needed depends on the embodiment
of the boiler in question, particularly the gas discharge pipe accommodated therein.
Said gas discharge pipe usually ends at a location within the housing of the boiler,
which can be reached through a hole in the housing wall onto which the casing can
be attached. The hole can be bounded by the material of the housing wall itself, or
by a combined flange/collar, in which the flange has been attached to the housing
wall and the collar forms a means for connection to the casing. Casing and inner pipe
adapter are placed as an assembly, in which the fitter should ensure a good connection
of the connection pipe to the gas discharge pipe situated in the boiler, which may
be difficult due to lack of a good overview.
[0006] It is an object of the invention to improve on this.
[0007] From one aspect the invention to that end provides an adapter for two concentric
pipes for gas devices, particularly an inner pipe for discharge of flue gasses of
a boiler to the outside and an outer casing which, together with the inner pipe, defines
an annular outer pipe for supply of combustion air to the boiler, comprising an inner
pipe adapter and an outer pipe adapter, which each have a lower end and an upper end,
that can each respectively be coupled to further first pipes leading to the boiler
and to second pipes leading away from the boiler and to a discharge structure, in
which the inner pipe adapter is provided with condensation interception means and
with condensation drain means and is provided above the lower end of the outer pipe
adapter with a passage for fitting accommodation of an inner pipe at boiler side.
[0008] In that way the connection pipe is actually uncoupled from the inner pipe adapter
and in production and stocking one type of inner pipe adapter will suffice and the
connection pipe can be produced separately in two or more versions, in accordance
with a male and female end or length. The fitting is then simplified as well, as the
fitter is able to easily place the separate connection pipe on the gas discharge pipe
situated in the boiler, and is then able to arrange the adapter with the outer pipe
adapter to the boiler wall and the inner pipe adapter over the connection pipe in
a controlled way. The inner pipe adapter can furthermore be easily inserted into the
outer pipe adapter.
[0009] It is noted that from Utility model 29705212 a connection assembly is known for connection
of an outer pipe and an inner pipe concentric therewith to connection pipe stubs in
the boiler, said connection pipe stubs having the same diameter as the pipes. The
connection for the outer pipe forms a shell provided with two flanges, which shell
is put around the pipe stub at the boiler and around the lower end of the outer pipe,
after which the flanges are riveted or fastened to each other with bolts. The connection
for the inner pipe comprises a piece of pipe that is placed around the lower end of
the inner pipe and around the upper end of a connection pipe, which connection pipe
itself is accommodated with its lower end in the connection pipe stub on the boiler.
Within the connection pipe a piece of pipe is placed that has been formed with a narrowing,
a condensation drain pipe being placed at the level of the narrowing of the piece
of pipe, said condensation drain pipe being radially extending outwardly through the
connection shell for the outer pipe, which condensation drain drains condensation
intercepted in the annular space between the narrowing of the piece of pipe and the
connection pipe.
[0010] Preferably the passage is situated at the level of the condensation drain means,
so that the length of the inner pipe adapter in boiler direction is as small as possible.
Such an inner pipe adapter is easier to produce, particularly injection moulding is
more feasible.
[0011] Preferably the condensation interception means define an annular channel and the
passage also forms an annular inner wall for the annular channel, and the wall forming
the passage thus having two functions.
[0012] The upper end of the inner pipe adapter may form a pipe stub here, that changes into
an outer wall of the annular channel.
[0013] In case the condensation drain means comprise a spout, that extends fittingly through
an opening in the outer pipe adapter, it is preferred that at its circumference the
spout is provided with an accommodation space for a sealing ring for sealing against
the opening in the outer pipe adapter, so that suction of air from the direct surroundings
of the boiler is counteracted. The accommodation space can be defined in a simple
manner by two circumferential ribs on the spout that are consecutive in spout direction.
[0014] For improvement of the accuracy of placing the inner pipe adapter in a plane transverse
to the pipe axis, it is preferred that near the spout the inner pipe adapter is provided
with stop means for abutment against the inner surface of the outer pipe adapter,
which stop means preferably are situated at the lower side of the spout.
[0015] Without diminishing the ease with which the inner pipe adapter can be placed in the
outer pipe adapter too much, the short design of the inner pipe adapter makes it possible
to provide it with one or more radial spacer means extending away from the spout,
for engaging the inner surface of the outer pipe adapter. In this way the position
of the inner pipe adapter can in a reliable way be at least almost perfectly concentric
with respect to the outer pipe adapter, which facilitates the installation of the
pipes.
[0016] It is preferred here that the inner pipe adapter is provided with a spacer member
that extends diametrically away from the spout, and which is preferably provided with
an inclined edge. As a result the insertion of the inner pipe adapter is facilitated,
as well as the stability of the inner pipe adapter after placing.
[0017] Preferably positioning means are provided on the inner wall of the outer pipe adapter
for positioning the spacer means in axial direction, so that the inner pipe adapter
can also be correctly placed in axial direction in a reliable manner.
[0018] Further reliability in the placing of the inner pipe adapter is obtained when positioning
means are provided on the inner wall of the outer pipe adapter for positioning the
spacer means in circumferential direction.
[0019] Yet further reliability in the placing of the inner pipe adapter is obtained when
the spacer means and the positioning means engage each other over a length in axial
direction, so that tilting of the inner pipe adapter is counteracted.
[0020] From a further aspect the invention provides in an adapter having an annular condensation
interception channel and connected spout, in which the bottom of the annular channel
is inclined with respect to the centre line of the inner pipe adapter, in which the
spout connects to the lowest point of the annular channel. The inclined bottom of
the annular channel guarantees a smooth condensation drainage, in which it is not
objectionable when the adapter is slightly obliquely tilted, in a direction away from
the spout.
[0021] In one embodiment the lower ends of the inner pipe adapter and the outer pipe adapter
have a diameter of 60 mm and 100 mm, respectively, and/or the upper ends of the inner
pipe adapter and the outer pipe adapter have a diameter of 80 mm and 125 mm, respectively.
[0022] In a further embodiment of the adapter according to the invention the outer pipe
adapter is provided with a flange member that is formed as a unity therewith, for
attachment to a boiler housing.
[0023] Alternatively the outer pipe adapter is provided with a flange member that can be
coupled thereto, for attachment to a boiler housing.
[0024] For ease of placing the flange member is provided with a circumferential series of
attachment holes.
[0025] It is preferred that the inner pipe adapter and the outer pipe adapter have each
been manufactured by means of injection moulding.
[0026] From a further aspect the invention provides an adapter for use in parallel systems,
particularly an adapter for an inner pipe for discharge of flue gasses of a boiler
to the outside with the lower end for connection to a pipe at the boiler side and
an upper end for connection to a pipe at discharge side, in which the adapter is provided
with condensation interception means and with condensation drain means, in which the
condensation interception means define an annular channel, and in which the adapter
is provided with a passage for fitting accommodation of an inner pipe at boiler side,
in which the passage also forms an annular inner wall for the annular channel. Preferably
the upper end of the pipe adapter forms a pipe stub, which changes into an outer wall
of the annular channel.
[0027] The bottom of the annular channel preferably is positioned inclined with respect
to the centre line of the pipe adapter, in which the spout connects to the lowest
point in the annular channel.
[0028] From a further aspect the invention provides an assembly of an adapter according
to the invention and a connection pipe at boiler side, that is detachably and fittingly
accommodated in the passage in the inner pipe adapter or adapter, respectively.
[0029] The invention will be elucidated on the basis of the exemplary embodiment shown in
the attached drawings, in which:
Figure 1 shows a cross-section of an arrangement having an adapter assembly according
to the invention;
Figure 2 shows a view in perspective of the adapter assembly of figure 1; and
Figure 3 shows the adapter assembly of figure 2, in exploded view.
[0030] Figure 1 shows the boiler or gas device of the closed type 1, in which a burner has
been positioned that has not been further shown. The flue gas discharge and the combustion
air supply are concentric with respect to each other here. In the upper wall 3 of
the housing a passage has been made for the exchange of the gasses. The combustion
air is sucked in downwards through the annular opening by the burner, and the flue
gasses are discharged via a boiler-fixed piece of pipe 55, onto which in an indirect
manner the adapter 2 has been arranged.
[0031] The adapter 2 comprises an outer casing 6 and an inner member 7 that defines a pipe-shaped
passage 10.
[0032] The casing 6 has a lower portion 22, which in this example may have a diameter of
100 mm, which portion 22 changes into a wider upper portion 24 via a conically flaring
portion 23, which upper portion 24 in this example may have a diameter of 125 mm.
[0033] The lower portion 22 is provided with a groove 28, which with protrusions 27 on a
collar 5 of flange 4 may form a bayonet catch. The flange 4 is provided with holes
32 for attachment, for instance by means of screws, to the upper wall 3 of the boiler
housing. In this way the casing 6 can easily be placed and attached on top of the
opening in the upper wall 3.
[0034] As can be seen in figure 2 the conical portion 23 is at one location provided with
a hole 40 for a condensation drain pipe 14 to be further discussed.
[0035] To the side that is diametrically opposite, just above the transition of the conical
portion 23 to the upper portion 24, an accommodation space has been realised by means
of two little ribs 20 extending in axial direction, for the edge 21 of a partition
19 yet to be discussed.
[0036] At the top the upper portion 24 is provided with an annular chamber 25 in which a
sealing 26 that is known per se, is accommodated, which sealing is provided with an
inclined radially inwardly extending lip. Said sealing 26 seals against the outside
of an outer pipe 30, which extends further towards the discharge structure (not further
shown).
[0037] The inner part or condensation interception piece 7 has an upper portion 8 that is
circle-cylindrical and at the upper end is provided with a radially opening annular
chamber 9 for accommodation of a sealing ring 57. In this way an inner pipe is received
in a sealing manner, which inner pipe also leads to the discharge structure that is
not shown.
[0038] In the passage 10 an annular chamber 11 is also provided, in which a simple 0-sealing
ring 56 is accommodated. In it a separate piece of pipe 50 -adapted to the installation
in question- can be accommodated in a sealing manner, adjustable in axial direction.
This piece of pipe 50 has a widened lower portion 52, in which an annular chamber
53 is provided that opens radially to the inside, for a sealing ring 54. In this way
the boiler-fixed piece of pipe 55 can be received in a sealing manner.
[0039] The condensation interception piece has a collar 12 which is a continuation of the
passage 10. Said collar together with the wall portion 8 defines an annular channel
13 for the interception of condensation that flows downwards along the inner surface
of the inner pipe 29 and may not end up in the boiler 1. The bottom 31 of the annular
channel runs inclined, and such that the highest point is shown in figure 1 at the
left-hand side, and the lowest point is shown at the location of the entrance of the
spout 14. The inclined bottom is schematically shown by means of a dotted line S.
[0040] At its circumference the spout 14 is provided with double circumferential ribs 15a,
15b which define an accommodation space for a sealing ring 16. With this ring 16 the
sealing takes place in the hole 50 in the casing 6.
[0041] Below the spout 14 the condensation drain piece is provided with two shoulders 18a
and 18b which may abut the inner surfaces present there in casing 6, as shown in figure
1. In this way the location of the spout 14 in the direction to the right as seen
in the drawing is secured. Shoulder 18a changes into a widened lower edge 17 of the
passage 10 and of the inner part 7. The lower edge 17 is situated at the location
of the transition of the portions 22 and 23 of the casing 6.
[0042] At the diametrically opposite side, a partition 19 is integrally formed on the condensation
interception piece, which partition 19 with the end edge 21 fits in the accommodation
space between the said ribs 20 and is provided with an inclined lower edge 19a.
[0043] During mounting the fitter may first, with overview, arrange the piece of pipe 50
on piece of pipe 55. Subsequently he takes the assembly of casing 6 and including
the condensation interception piece 7 that has already been inserted into it from
the top in the factory, and that is accommodated in it in a press fitting manner.
During said insertion in the factory, the spout 14 will be kept slightly downwardly
inclined, so that it may pass through the opening 50. When the sealing ring 16 has
ended up at the opening 50, tilting of the condensation interception piece 7 will
be able to take place in the direction M, in which the edge 21 comes to lie fittingly
between the ribs 20. The inclined lower edge 19a facilitates the said tilting movement.
When the lower edge of the partition 19 at the location of the transition to the edge
21 has arrived at the indicated location of the transition in the wall of casing 6,
the shoulder 18b will also abut. The condensation interception piece 7 is then retained
against displacement to the left or to the right, as seen in the drawing, but by means
of the ribs 20 also retained against tilting about a line that is transverse to the
discharge centre line.
[0044] The fitter places the adapter assembly 2 with the flange 4 on the upper wall 3 of
the boiler 1. Here the passage 10 and the collar 12 are simply slid over the narrowed
upper portion of the piece of pipe 50. Finally the flange 4 is secured to the upper
wall 3 of the housing of the boiler 1 by means of screws, and the entire adapter 2
is secured in that way. After that the inner pipe 29 and the outer pipe 30 can be
placed in a simple manner.
[0045] It is noted that it is also an option to attach the flange 4 beforehand on the upper
wall 3, and then later on to attach the adapter 2, with the casing 6, to the collar
5 of the flange 4 by means of the said bayonet coupling 27, 28.
[0046] Both casing 6 and condensation interception piece 7 may each be injection moulded
as an element forming one unit, for instance from cast aluminium.
1. Adapter for two concentric pipes for gas devices, particularly an inner pipe for discharge
of flue gasses of a boiler to the outside and an outer casing which, together with
the inner pipe, defines an annular outer pipe for supply of combustion air to the
boiler, comprising an inner pipe adapter and an outer pipe adapter, which each have
a lower end and an upper end, that can each respectively be coupled to further first
pipes leading to the boiler and to second pipes leading away from the boiler and to
a discharge structure, in which the inner pipe adapter is provided with condensation
interception means and with condensation drain means and is provided above the lower
end of the outer pipe adapter with a passage for fitting accommodation of an inner
pipe at boiler side.
2. Adapter according to claim 1, in which the passage is situated at the level of the
condensation drain means.
3. Adapter according to claim 2, in which the condensation interception means define
an annular channel and the passage also forms an annular inner wall for the annular
channel, in which the bottom of the annular channel is preferably inclined with respect
to the centre line of the inner pipe adapter, in which the spout connects to the lowest
point of the annular channel.
4. Adapter according to claim 3, in which the upper end of the inner pipe adapter forms
a pipe stub, that changes into an outer wall of the annular channel.
5. Adapter according to any one of the preceding claims, in which the condensation drain
means comprise a spout, that extends fittingly through an opening in the outer pipe
adapter.
6. Adapter according to claim 5, in which at its circumference the spout is provided
with an accommodation space for a sealing ring for sealing against the opening in
the outer pipe adapter, which accommodation space preferably is defined by two circumferential
ribs on the spout that are consecutive in spout direction.
7. Adapter according to claim 5 or 6, in which the inner pipe adapter near the spout
is provided with stop means for abutment against the inner surface of the outer pipe
adapter, which stop means preferably are situated at the lower side of the spout.
8. Adapter according to any one of the claims 5-7, in which the inner pipe adapter is
provided with one or more radial spacer means for engaging the inner surface of the
outer pipe adapter which means extend away from the spout, in which the inner pipe
adapter preferably is provided with a spacer member that extends diametrically away
from the spout, and which is preferably provided with an inclined edge.
9. Adapter according to claim 8, in which positioning means are provided on the inner
wall of the outer pipe adapter for positioning the spacer means in axial direction.
10. Adapter according to claim 8 or 9, in which positioning means are provided on the
inner wall of the outer pipe adapter for positioning the spacer means in circumferential
direction.
11. Adapter according to any one of the claims 8-10, in which the spacer means and the
positioning means engage each other over a length in axial direction.
12. Adapter according to any one of the preceding claims, in which the lower ends of the
inner pipe adapter and the outer pipe adapter are different in diameter with respect
to the upper ends of the inner pipe adapter and the outer pipe adapter.
13. Adapter according to any one of the preceding claims, in which the lower ends of the
inner pipe adapter and the outer pipe adapter have a diameter of 60 mm and 100 mm,
respectively.
14. Adapter according to any one of the preceding claims, in which the upper ends of the
inner pipe adapter and the outer pipe adapter have a diameter of 80 mm and 125 mm,
respectively.
15. Adapter according to any one of the preceding claims, in which the outer pipe adapter
is provided with a flange member that is formed as a unity therewith, for attachment
to a boiler housing.
16. Adapter according to any one of the claims 1-14, in which the outer pipe adapter is
provided with a flange member that can be coupled thereto, for attachment to a boiler
housing.
17. Adapter according to claim 15 or 16, in which the flange member is provided with a
circumferential series of attachment holes.
18. Adapter according to any one of the preceding claims, in which the inner pipe adapter
and the outer pipe adapter have each been manufactured as one piece by means of injection
moulding.
19. Adapter for an inner pipe for discharge of flue gasses of a boiler to the outside
with the lower end for connection to a pipe at the boiler side and an upper end for
connection to a pipe at discharge side, in which the adapter is provided with condensation
interception means and with condensation drain means, in which the condensation interception
means define an annular channel, and in which the adapter is provided with a passage
for fitting accommodation of an inner pipe at boiler side, in which the passage also
forms an annular inner wall for the annular channel.
20. Adapter according to claim 19, in which the upper end of the pipe adapter forms a
pipe stub, which changes into an outer wall of the annular channel, in which preferably
the bottom of the annular channel is positioned inclined with respect to the centre
line of the pipe adapter, in which the spout connects to the lowest point in the annular
channel.
21. Assembly of an adapter according to any one of the preceding claims and a connection
pipe at boiler side, that is detachably and fittingly accommodated in the passage
in the inner pipe adapter or adapter, respectively.