[0001] The invention relates to discharge structures for discharge structures for closed
gas appliances that extend through a wall of a building, particularly discharge structures
extending through facades
[0002] The invention further relates to parts for such a discharge structure.
[0003] Such discharge structures are widely known. The are usually provided with a double
line, namely a supply line for supply of combustion air to the boiler and a discharge
line concentrically situated within it for discharge of flue gasses from the boiler
to the outside.
[0004] The discharge structure should particularly in exterior wall ducts provide a transition
of the vertical line portion coming out of (or going to) the boiler -usually pipe
stubs on the exit/entrance of the boiler- to the horizontal line portion extending
through the facade. To that end a arch piece can be used which comprises two concentric
pipe members, that can be connected to both concentric lines
[0005] It is an object of the invention to provide a discharge structure which can be mounted
easily with as few tools as possible.
[0006] It is furthermore an object of the invention to provide a discharge structure having
favourable flow properties.
[0007] From one aspect the invention to that end provides a discharge structure for closed
gas appliances, comprising two pipes extending concentrically into each other, in
which the outer pipe and the inner pipe each comprise an inner end at the boiler side
and an outer end at the side of the outside air, in which the inner pipe is a flue
gas discharge pipe and both pipes define an annular line with each other for air supply
to the boiler, in which the outer pipe at the inner end is provided with a pipe bend
or bend piece which consists of at least two members, that are provided with connection
surfaces which extend at least with a directional component in flow direction, in
which the pipe bend is held in its place in the discharge structure by having its
ends attached to or on the parts of the air supply line connecting to the pipe bend.
[0008] In this way the mounting ease for the fitter is strongly increased, because the pipe
bend can be brought in its place in radial/tangential direction around the bent inner
pipe. This can particularly even take place when the inner pipe has already been mounted.
Because the pipe bend can be placed after the inner pipe has been placed, the fitter
can check the connection of the inner pipe to the boiler. Furthermore as a result
of the manner of dividing, forming this portion of the outer pipe is made easier and
there is a larger degree of freedom in design details. Because of the connecting portions
of the air supply line, in particular the connection to the boiler and the portion
of the outer pipe situated upstream, the pipe bend can be kept in its place independent
of the inner pipe, so that size tolerances are less troubling when mounting. In the
bend the outer pipe and the inner pipe need not necessarily run concentrically.
[0009] Preferably the connection surfaces extend in flow direction, so that a dividing area
is obtained which is as short as possible. Preferably the pipe bend is built up from
two shell members.
[0010] In other words the invention provides a discharge structure, in which the outer pipe
is provided with a pipe bend at the inner end, which is longitudinally divided into
two halves placed against each other, that preferably are symmetrical.
[0011] The pipe bend members may be connected to each other by means of screws, an elastic
circumferential band, a snap connection or the like, preferably in a non-permanent
manner.
[0012] Preferably profiles are provided for sealingly clamping the members of the pipe bend
to each other. The fitter then arranges the pipe bends around the inner pipe and subsequently
attaches them onto each other by means of clamping profiles, which also ensure sealing.
[0013] It is also possible to provide that the outer pipe is formed for radially engaging
the outer ends of the pipe bend in a clamping manner, which makes the placement very
easy. For that purpose said ends preferably are situated radially offset to the inside,
in order to thus define a portion which is narrowed over a wall thickness.
[0014] For further ease of placement it is preferred that the inner pipe and/or the outer
pipe is/are built up from pipe parts that are telescopically slidable with respect
to each other.
[0015] The invention also provides a pipe bend for discharge structures, consisting of at
least two parts, which are provided with connection surfaces which extend at least
with a directional component in flow direction.
[0016] Preferably the inner edge is bent, preferably with a same curvature centre point
as the outer edge of the pipe bend.
[0017] The invention further provides a method for fitting a discharge structure to gas
appliances, provided with a gas discharge line and an air supply line situated concentrically
around it, in which first of all an inner pipe part for gas discharge is connected
to the gas appliance and after that an outer pipe part that consists of two or more
longitudinal members is arranged from aside around the inner pipe part, the longitudinal
members are placed against each other, in particular connected to each other and the
outer pipe part is connected to the gas appliance.
[0018] For further ease of mounting, in the discharge structure according to the invention
a supply end piece is placed at the outer end of the inner pipe, which supply end
piece is provided with air flow guiding means that are situated in flow line with
the annular line and with means for restraining the inner pipe in outward direction.
[0019] Preferably the restraining means comprise stop surfaces cooperating with the end
edge of the inner pipe.
[0020] Preferably the supply end piece comprises means for attachment to the outer end of
the outer pipe, preferably for a snap attachment. The supply end piece thus forms
a means with which the outer pipe and the inner pipe are secured in outward direction
with respect to each other.
[0021] For even further ease of mounting in the discharge structure according to the invention
a discharge end piece can be placed in the outer end of the inner pipe, which discharge
end piece is provided with discharge gas flow guiding means that are situated in flow
line with the gas discharge line and in which the discharge end piece is provided
with means for restraining the supply mouthpiece in outward direction, preferably
in the form of stop surfaces.
[0022] Preferably said restraining means comprise stop surfaces cooperating with the end
edge of the supply mouthpiece.
[0023] Preferably the end mouthpiece is attached here to the inner pipe, preferably by means
of clamping it thereon.
[0024] It will be understood that the supply mouthpiece and/or discharge end piece can also
be used in other discharge structures, for instance the one having a straight course
from the boiler.
[0025] The invention further provides a pipe suitable for use as an inner pipe for the discharge
structure according to the invention.
[0026] Preferably a pipe, formed as a unity having substantially an L-shape in side view
and having a relatively long stretched portion and a relatively short portion perpendicular
to it, is used as inner pipe member.
[0027] From a further aspect the invention provides a discharge structure for closed gas
appliances, comprising two pipes extending concentrically into each other, in which
the outer pipe and the inner pipe each have an inner end at the side of the boiler
and an outer end at the side of the outside air, in which the inner pipe is a flue
gas discharge pipe and both pipes define a annular line with each other for air supply
to the boiler, the inner pipe comprising two portions, which in flow direction are
in line which each other, forming a unity with each other and are situated at an angle
to each other.
[0028] By using an inner pipe that is already provided with a bend, parts and their mounting
are economized on. As a result furthermore fewer transitions, and thus fewer sealing
provision are necessary and less potential condensation locations (corners) are present.
Furthermore the freedom in making the bent portion of the outer pipe is increased
as a result.
[0029] Preferably said angle is approximately 90 degrees, so that for the turning from horizontal
to vertical for the inner pipe no further pipe parts are necessary in principle. In
other words the inner pipe preferably comprises an elbow portion formed with it as
a unity.
[0030] From another aspect the invention to that end provides a discharge structure for
closed gas appliances, comprising two pipes extending concentrically into each other,
in which the outer pipe and the inner pipe each comprise an inner end at the side
of the boiler and an outer end at the side of the outside air, in which the inner
pipe is a flue gas discharge pipe and both pipes define and annular line with each
other for air supply to the boiler, in which at the inner end the inner pipe is provided
with arched portion formed with it as a unity.
[0031] The invention will below be elucidated on the basis of the exemplary embodiments
shown in the attached drawings, in which:
Figure 1 shows a disassembled side view on the discharge structure according to the
invention, at the location of an exterior wall duct near a boiler;
Figure 2 shows a disassembled top view on the discharge structure of figure 1;
Figure 3 shows the discharge structure according to figures 1 and 2, in cross-section
and in mounted situation;
Figure 4 shows a detail of the connection of the parts of the pipe bend according
to the invention; and
Figure 5 shows a cross-section of an alternative arrangement of a pipe bend according
to the invention.
[0032] In figure 1 the boiler arrangement 1 is shown, comprising a boiler 3 and a discharge
structure 4 for it. The boiler 3 has a pipe stub 24 in the top side for connection
of a gas discharge pipe and a pipe stub 25 situated concentrically around it for connection
of an air supply pipe.
[0033] The boiler arrangement 1 is near an exterior wall or facade 2, in which a duct 11
has been made through which the discharge structure 4 can extend to form a connection
between the outside air and the boiler 3, in particular the aforementioned pipe stubs
24, 25.
[0034] The discharge structure 4 comprises a first inner pipe 5 and a second inner pipe
9 telescopically and snugly accommodated therein, both pipes for instance made of
aluminium. The first inner pipe 5 consists of a pipe portion 6 which is bend over
90 degrees and a straight pipe portion 7 formed with it as a unity. At the inner end
the first inner pipe 5 is provided with an annular chamber 30 opening to the inside,
in which a rubber sealing ring 18 can be accommodated for sealing against the pipe
stub 24. At the outer end the first inner pipe 5 is provided with an annular chamber
28 opening to the inside, in which a rubber sealing ring 16 can be accommodated for
sealing the straight pipe portion 7 against the second inner pipe 9.
[0035] The discharge structure 4 further comprises a straight outer pipe 8 and a second
outer pipe 10 telescopically and snugly accommodated therein, both pipes for instance
made of zenzidmir galvanized steal or synthetic material. Preferably the first outer
pipe 8 is painted white for the sight inside the house. For the connection of the
outer pipes 8, 10 to the pipe stub 25 a pipe bend 19 is provided, which is bent around
the centre point M, over 90 degrees with both the inner edge and the outer edge, as
shown in figure 1. The pipe bend 19 can be made by means of injection moulding with
synthetic material or an aluminium or aluminium alloy, and then be painted white for
aesthetic reasons.
[0036] At the inner end the first outer pipe 8 is provided with an annular chamber 31 opening
to the outside, in which chamber a rubber sealing ring 33 can be accommodated for
sealing against the inner wall of the pipe bend 19. At the outer end the first outer
pipe 8 is provided with an annular chamber 32 opening to the inside, in which chamber
a rubber sealing ring 17 can be accommodated for sealing against the outer surface
of the second outer pipe 10. The second outer pipe is furthermore provided with snap
holes 29 at its outer end, of which snap holes the function will be explained below.
[0037] The pipe bend 19 is divided into two identical longitudinal halves 20a, 20b. Said
longitudinal halves are designed such that they can easily be released from a mould.
They are both provided with outer edges 40, 41 (see figure 41) with which they can
be placed flat against to each other. The inner edges of said longitudinal halves
are formed correspondingly. The outer edges 40, 41 -and therefore the inner edges
as well- are formed with a tangential turn, to define a hook shape. By snapping a
rubber profile 21 which is fittingly formed with it like a kind of zipper gasket over
the joined edges 40, 41 the longitudinal halves 20a, 20b can thus be secured to each
other along said edge and also ensure sealing of said edge. The longitudinal halves
of the pipe bend may possibly be secured to each other by means of rivets or screws.
[0038] In figure 5 an alternative is shown, in which the inner end of the pipe bend 119
( which just like the pipe bend 19 is longitudinally divided) is slid into an annular
groove 125 on the boiler an at the outer end is provided with a narrowed portion 123.
Both longitudinal halves 122a, 122b are placed one after the other into the groove
125, then placed (plain joined) with their longitudinal edges against each other,
and subsequently the pipe 110 is clampingly slid over the portion 123 with the inner
end, after which the pipe bend 119 is retained at both ends. An additional fastener
for the longitudinal edges can be dispensed with here, as a result of the clamping
at the ends. A sealing along said longitudinal edges could also possibly be dispensed
with.
[0039] In both cases the pipe bend 19, 119 can be retained independently from the inner
pipe/inner pipe bend.
[0040] At the outer end the discharge structure 4 further comprises an air flow guide 12,
for instance made of synthetic material or cast aluminium, comprising an outer ring
34, an inner ring 38 situated radially within it and axially outside of it and a number
of radial fins 26 formed as a unity with said inner ring. At its inner surface the
outer ring 34 is provided with snap protrusions (not shown), which can snap into the
holes 29 in the second outer pipe 10, in order to fix the guide 12 on the pipe 10.
The fins 26 abut the outer surface of the second inner pipe 9. The guide 12 thus provides
a means for concentrically retaining the second inner pipe 9 with respect to the second
outer pipe 10. At the outer end the inner ring 38 is provided with a shoulder flange
35 extending to the inside, against which the end edge of the second inner pipe 9
abuts. In this way the guide 12 provides a means for securing the second inner pipe
9 axially to the outside with respect to the second outer pipe 10.
[0041] At the inner end the air flow guide 12 is provided with a little flange 37, on which
a rubber sealing sleeve 14 can be attached. At the outer end the air flow guide 12
is provided with an opening bounded by the flange 35, in which opening a gas flow
guide or gas flow grid 13, for instance made by casting aluminium or an alloy of aluminium,
can be clamp fittingly accommodated. Said grid 13 is provided with an middle bush
36 from which radial fins 27 extend. The fins 27 and the bush 36 are wing-shaped in
cross-section for lowered flow resistance. The fins 27 at the outer end form an annular
stop 39 extending to the inside, with which stop the end edge of the inner pipe 9
is retained. Thus the axial and radial securing of outer pipe 10 and inner pipe 9
is achieved.
[0042] The mounting takes place in the following manner. The parts 9, 10, 12 and 13 and
sleeve 14 are pre-assembled in the factory. A snap connection is realised in the holes
29 and the gas flow guide 13 is clampingly fixed.
[0043] Said assembly is inserted into the hole 11 from the outside. Subsequently the first
outer pipe 8, which has been provided with rubber rings 17 and 33 beforehand, is slid
from the inside around the second outer pipe 10. Subsequently a sealing sleeve 15
is placed on the inner end of the first outer pipe 8, is that said sleeve, just like
sleeve 14, is pressed against the surface of the wall 2 and the passage 11 outside
the outer pipe 8/10 is closed off. After that the inner pipe 5, which has been provided
with rings 16 and 18 beforehand, is slid into the second inner pipe, and the inner
end is fitted onto the pipe stub 24 -possibly after rotation about the centre line
of the straight pipe portion-.
[0044] The outer pipes 8, 10 and the inner pipes 5 and 9 are brought at the correct length
by extending or retracting. The rubber ring 23 is placed on the pipe stub 25. Finally
the two shells or longitudinal halves 20a, 20b with profiles 21, 22 are taken and
placed on either side around the pipe bend 6, the ends abutting the rubber rings 33
and 23, and the longitudinal edges against each other. By attaching the rubber profiles
21 and 22 on the joined longitudinal edges after that, the pipe bend 19 is also secured.
The pipe bend is then held concentrically with respect to the inner pipe by the pipe
stub 25 and the outer pipe 8. The inner pipe 5 is retained concentrically with respect
to the outer pipe by the pipe stub 24 and the air flow guide 12. No additional means
are needed for concentrically retaining the parts of the discharge structure.
[0045] Thus the discharge structure 4 is simple to build up and can easily and quickly be
placed without tools. The flow resistance is low because there are no transitions
and the presence of broad pipe bends, both in the gas discharge and in the air supply.
[0046] When the inner pipe 5 is formed by bending this entails the advantage that the wall
thickness desired for bending also renders the inner pipe particularly suitable for
accommodation in condensing arrangements.
1. Discharge structure for closed gas appliances, comprising two pipes extending concentrically
into each other, in which the outer pipe and the inner pipe each comprise an inner
end at the boiler side and an outer end at the side of the outside air, in which the
inner pipe is a flue gas discharge pipe and both pipes define an annular line with
each other for air supply to the boiler, in which the outer pipe at the inner end
is provided with a pipe bend which consists of at least two members, that are provided
with connection surfaces which extend at least with a directional component in flow
direction, in which the pipe bend is held in its place in the discharge structure
by having its ends attached to or on the parts of the air supply line connecting to
the pipe bend.
2. Discharge structure according to claim 1, in which the connection surfaces extend
in flow direction.
3. Discharge structure according to claim 1 or 2, in which the pipe bend is built up
from two shell members, which are preferably longitudinally divided.
4. Discharge structure according to claim 1, 2 or 3, further provided with profiles for
sealingly clamping the members of pipe bend to each other.
5. Discharge structure according to claim 1, 2 or 3, in which the outer pipe is formed
for radially engaging the outer ends of the pipe bend in a clamping manner, in which
preferably the longitudinal edges are situated plain joined against each other.
6. Discharge structure according to any one of the preceding claims, in which the pipe
bend is attached to the rest of the supply line only at it ends, on parts of the outer
pipe that connect to the pipe bend.
7. Discharge structure according to any one of the preceding claims, in which the outer
pipe is built up from pipe parts that are telescopically slidable with respect to
each other.
8. Discharge structure according to any one of the preceding claims, in which at the
outer end of the inner pipe a supply end piece is placed, which is provided with air
flow guiding means that are situated in flow line with the annular line and with means
for restraining the inner pipe in outward direction.
9. Discharge structure according to claim 8, in which the restraining means comprise
stop surfaces cooperating with the end edge of the inner pipe.
10. Discharge structure according to claim 8 or 9, in which the supply end piece is furthermore
provided with means for connection to the outer end of the outer pipe, preferably
snapping means.
11. Discharge structure according to claim 8, 9 or 10, in which a discharge end piece
is placed in the outer end of the outer pipe, which end piece is provided with discharge
gas flow guiding means that are situated in flow line with the gas discharge line
and in which the discharge end piece is provided with means, preferably stop surfaces,
for restraining the supply mouthpiece in outward direction, in which the discharge
mouthpiece is attached to the inner pipe, preferably by clamping.
12. Discharge structure according to any one of the preceding claims, in which the inner
pipe is built up from pipe parts that are telescopically slidable with respect to
each other.
13. Discharge structure according to any one of the preceding claims, in which the inner
pipe comprises two portions, which in flow direction are in line with each other,
form a unity with each other and are at an angle of approximately 90 degrees with
respect to each other and/or the inner pipe comprises an elbow formed with it as a
unity.
14. Pipe bend suitable for use as pipe bend for the discharge structure according to any
one of the preceding claims.
15. Pipe bend for the air supply line of discharge structures for closed gas appliances,
which pipe bend consists of at least two members, which are provided with connection
surfaces that can be connected to each other during the placement of the discharge
structure, which connection surfaces extend at least with a directional component
in flow direction, in which the two members are provided with means for support on
parts of the air supply line that are connected to the pipe bend.
16. Pipe bend according to claim 15, in which the connection surfaces extend in flow direction.
17. Pipe bend according to claim 15 or 16, in which the pipe bend is built up from two
shell members.
18. Pipe bend according to claim 17, which is longitudinally divided.
19. Pipe bend according to any one of the claims 15-18, in which the inner edge is bent,
preferably with a same curvature centre point as the outer edge of the pipe bend.
20. Pipe bend according to any one of the claims 15-19, further comprising means for holding
the connection surfaces plain joined to each other.
21. Method for fitting a discharge structure to gas appliances, provided with a gas discharge
line and an air supply line situated concentrically around it, in which first of all
an inner pipe part for gas discharge is connected to the gas appliance and after that
an outer pipe part that consists of two or more longitudinal members is arranged from
aside around the inner pipe part, the longitudinal members are placed against each
other, in particular connected to each other and the outer pipe part is connected
to the gas appliance.
22. Method according to claim 21, in which a pipe, formed as a unity having substantially
an L-shape in side view and having a relatively long stretched portion and a relatively
short portion perpendicular to it, is used as an inner pipe part.