[0001] This invention relates to a ventilation device for the natural supply of air or discharge
of air, comprising an air flow channel wherein a first, a second and a third regulating
valve are arranged so as to be able to rotate or hinge in series, in such a way that
during rotating or hinging of these regulating valves the flow rate of air through
this air flow channel is regulated.
[0002] Regulating valves are arranged in series in an air flow channel when said regulating
valves are arranged one after another in a direction of the flow of air through this
air flow channel and are each per se provided in order to be able to close off the
air flow channel.
[0003] This invention is situated predominantly in the framework of the provision of a ventilation
device for the natural supply of air or discharge of air, provided for placing in
or on a window, door, roof surface or external wall of a building designed in accordance
with what is known as the passive house concept or of a building in regions having
low to very low outside temperature during the heating season.
[0004] What are known as passive house buildings usually possess a completely mechanical
ventilation system provided with a heat recovery unit. In this way, the losses of
energy via ventilation can be limited in the event of low outside temperatures. Because
of the high degree of insulation and the high air-tightness of the building shell
of buildings of this type, the gains of heat via solar irradiation, internal heat
loads et al. are usually higher than the losses of heat via transmission and ventilation.
There is therefore a great need to increase ventilation losses via the opening of
additional ventilation devices when the outside temperature is lower than the inside
temperature. However, existing ventilation devices for the natural supply of air or
discharge of air cannot be used for this purpose. That is to say, when losses of energy
are higher than gains of energy, it is desirable to limit as much as possible the
losses of heat through the building shell because there is only a small amount of
heating capacity and to avoid what are known as cold bridges because of the high degree
of insulation of the building shell. Losses of heat via the ventilation devices should
then also be limited as much as possible. When the ventilation device is closed, a
ventilation device of this type should then also possess high thermal resistance (or
a low coefficient of heat transmission or U value in W/m
2K), a high temperature factor f and high air-tightness.
[0005] As a reference, it may be stated that a ventilation device of this type attains preferably
at least thermal resistance and a temperature factor which are obtained by window
profiles.
Plastics material PVC windows made up of five chambers are to have in accordance with
Belgian standard NBN B62-002 at most a U value of 1.6 W/(m
2K). This value is also obtained by highly insulated aluminium window profiles. In
accordance with this same standard, a wooden frame made of hardwood must already have
a thickness of 120 mm in order to obtain a U value of 1.6 W/(m
2K).
[0006] In accordance with NBN B25.002-1, in houses in accordance with indoor climate class
2, at a minimum monthly average temperature of-8 °C, a temperature factor of at least
0.61 must be obtained for windows.
[0007] When providing ventilation devices for the natural supply of air or discharge of
air in passive house buildings, it should be possible to switch off one or two fans
of the mechanical ventilation system present when the ventilation devices are in use.
This entails a not inconsiderable additional gain in energy for passive house buildings
of this type.
[0008] Ventilation devices having high thermal resistance, a high temperature factor and
high air-tightness are desirable also in buildings in regions having low to very low
outside temperature during the heating season. That is to say, in such regions it
is desirable to have ventilation devices which allow the ventilation device to be
temporarily closed off while losing as little energy as possible, while at the same
time avoiding condensation or the formation of ice in or on the ventilation device.
[0009] However, in existing ventilation devices, it is not possible to limit losses of heat
to such a degree that said ventilation devices can be used in a passive house building
without having to make the air flow channel undesirably long. That is to say, the
total length of the air flow channel should be limited as much as possible in order
to limit material costs, to allow placement on glazing, etc.
[0010] In sliding grates it is not possible to sufficiently limit losses of heat, since
in that case at least one displaceable valve has at all times to be able to be displaced
with respect to a grate with punched holes. In this case, although insulation is currently
attached between the displaceable valves and the grate with punched holes, this insulation
has to be provided in such a way that the valves remain displaceable, so that substantial
losses of heat occur at all times because of limited air-tightness. These losses of
heat are in this case, viewed relatively, also greater than in comparable ventilation
devices, since a sliding grate of this type has a much more limited ventilation flow
rate than ventilation devices with regulating valves of comparable dimensions and
it is thus necessary to provide a larger surface area on sliding grates in order to
obtain the same ventilation flow rate and, as a result, greater losses of heat occur
for the same ventilation flow rate.
[0011] Also in the case of ventilation devices with two rotating regulating valves which
form part of the circumference of a hollow drum which is rotatably provided in the
air flow channel of this ventilation device (what are known as drum grates), it is
not possible to sufficiently limit losses of heat. It is possible to provide between
the rotatable drum and the air flow channel insulation which ensures as effectively
as possible that the air flow channel can be closed off with the aid of the regulating
valves and this insulation, when the rotating regulating valves are closed, these
regulating valves closing off the air flow channel at two different locations. Nevertheless,
this insulation should be provided in such a way that the drum remains rotatable in
the air flow channel, so that a ventilation device of this type is in practice not
very air-tight when closed.
[0012] An air flow channel can be closed off more effectively with the aid of hingeable
regulating valves in the air flow channel. However, a major drawback of ventilation
devices of this type is the fact that the position of regulating valves of this type
changes in an unintended manner in the event of the occurrence of gusts of wind.
[0013] WO 89/02970 describes a ventilation device of this type with a hingeable regulating valve which
can close off the air flow channel at two locations. In this way, during closing-off
of the air flow channel a volume of air is retained by this hingeable regulating valve.
A somewhat improved thermal resistance, temperature factor and air-tightness are thus
obtained. However, as a result of the fact that the position of this regulating valve
can change in an unintended manner in the event of the occurrence of sudden gusts
of wind, this ventilation device does not meet the stipulated objectives.
[0014] DE 299 10 662 describes a ventilation device wherein three regulating valves are arranged in series
in such a way that during rotating and/or hinging thereof the flow rate of air through
the air flow channel is regulated. When the air flow channel is closed off with the
aid of the outermost regulating valves, a volume of air can be retained by these regulating
valves. In this way too, somewhat improved thermal resistance, a higher temperature
factor and air-tightness are obtained. However, as stated hereinbefore, a major drawback
of this is the fact that the position of regulating valves of this type changes in
an unintended manner in the event of the occurrence of gusts of wind. This entails
not inconsiderable, and thus undesired, losses of heat.
[0015] The object of this invention is therefore also, as stated hereinbefore, to provide
a ventilation device for the natural supply of air or discharge of air, provided for
placing in or on a window, door, roof surface or external wall of a building designed
in accordance with what is known as the passive house concept or of a building in
regions having low to very low outside temperature during the heating season, this
ventilation device having high air-tightness, a maximum U value of 1.6 W/(m
2K) and a minimum temperature factor of 0.61 at a minimum monthly average temperature
of -8 °C.
[0016] This object of the invention is achieved by providing a ventilation device for the
natural supply of air or discharge of air, comprising an air flow channel wherein
a first, a second and a third regulating valve are arranged so as to be able to rotate
or hinge in series, in such a way that during rotating or hinging of these regulating
valves the flow rate of air through this air flow channel is regulated, the hinging
movement of at least two of the regulating valves being mutually mechanically coupled.
[0017] Mutually mechanically coupling the movement of at least two regulating valves greatly
reduces the risk of unexpected changes of the position of the regulating valves.
[0018] When closed, it is possible to create between these two regulating valves placed
in series at least two volumes of air which are screened off from the inside and outside
air. The air movement in these volumes of air is minimal, as a result of which the
thermal resistance is substantially increased.
[0019] In the case of at least one hinging regulating valve, said regulating valve can connect
exceedingly well in the known manners, such as for example with the aid of a resilient
part at the end of this regulating valve, when closed, to the air flow channel, as
a result of which, together with the other regulating valves, especially high air-tightness
of the ventilation device as a whole is obtained.
[0020] If two rotating regulating valves are provided, which form part of the circumference
of a hollow drum which is rotatably provided in the air flow channel of this ventilation
device (what are known as drum grates), then it is possible either to provide as the
third regulating valve a hinging regulating valve, which can ensure high air-tightness
when closed, or to provide as the third regulating valve a rotating regulating valve
which, together with a fourth rotating regulating valve, forms part of a second hollow
drum which is rotatably provided in the air flow channel. Thus, with two drums, three
volumes of air are screened off from the inside and outside air, as a result of which
the thermal resistance is increased still further, but as a result of which even better
air-tightness of the ventilation device is obtained between the inside air and the
outside air.
[0021] Of course, in addition to the first, the second and the third regulating valve, still
further regulating valves can be provided in series with these regulating valves in
the air flow channel. However, further regulating valves will merely entail smaller
gains in thermal resistance, temperature factor and air-tightness.
[0022] Preferably, in a ventilation device of this type according to the invention, the
movement of the aforementioned at least two regulating valves is mutually mechanically
coupled in such a way that during hinging or rotating of one of both regulating valves
in a first direction with respect to the air flow channel the other of both regulating
valves hinges or rotates in the opposite direction to this first direction with respect
to the air flow channel.
[0023] A coupling of this type produces, in the event of a difference in pressure over the
ventilation device, opposite forces, that is to say, on the one hand, a force which
seeks to open one of both regulating valves and, on the other hand, a force which
seeks to open the other of both regulating valves. Owing to the coupling of the movement
of both regulating valves, both forces which occur (substantially) cancel each other
out, thus stabilizing the entity formed by both regulating valves. The position of
these regulating valves will therefore also (substantially) not change in an unintended
manner in the event of the occurrence of gusts of wind.
[0024] In a specific embodiment of a ventilation device of this type, the movement of the
aforementioned at least two regulating valves is mutually mechanically coupled with
the aid of a rod mechanism.
[0025] Alternatively or additionally to the coupling with the aid of a rod mechanism, the
movement of these aforementioned two regulating valves can be mutually mechanically
coupled with the aid of a drum.
[0026] In the case of coupling with the aid of a drum, in a further specific embodiment,
the movement of the aforementioned at least two regulating valves can also be mutually
mechanically coupled as a result of the fact that the two regulating valves form part
of the circumference of a hollow drum which is arranged so as to be able to rotate
in the ventilation channel. This specific embodiment therefore corresponds to the
specific embodiment cited hereinbefore wherein what is known as a drum grate is provided
with one or more additional regulating valves.
[0027] Even more preferably, in a ventilation device according to this invention, the movement
of the first, the second and the third regulating valve is mutually mechanically coupled.
[0028] In a further preferred embodiment of a ventilation device according to this invention,
at least two of the regulating valves are embodied identically to one another. This
provides, in the case of regulating valves which do not form part of a drum, a major
advantage in terms of production as a result of the fact that producing one type of
regulating valve allows a plurality of regulating valves to be provided from this
ventilation device. In the case of coupled regulating valves on which opposite forces
act in the event of gusts of wind, it is also simpler to further design the ventilation
device in such a way that these opposite forces can cancel each other out almost completely.
[0029] Furthermore, in order to be able to easily clean and maintain the ventilation device,
preferably at least one of the regulating valves is releasably arranged.
[0030] A further specific embodiment of a ventilation device according to this invention
is provided with an actuator which can be used to activate the movement of the regulating
valves.
[0031] Furthermore, in order to automatically adapt the flow rate of air through the ventilation
device as a function of the difference in pressure between the inlet and the outlet
of the air flow channel, in a ventilation device according to this invention, a fourth
regulating valve is preferably arranged in series with the first, the second and the
third regulating valve, in such a way that during rotating and/or hinging of this
first, second, third and fourth regulating valve the flow rate of air through the
air flow channel is regulated, this fourth regulating valve being a self-regulating
valve.
[0032] A self-regulating valve of this type is a valve which can automatically adapt the
flow rate of air through a ventilation device, without being activated with the aid
of a sensor or a motor.
[0033] This invention will now be commented on in greater depth based on the subsequent
detailed description of a preferred embodiment of a ventilation device according to
this invention. The purpose of this description is exclusively to provide illustrative
examples and to indicate further advantages and particularities of this embodiment,
and may thus in no way be interpreted as a restriction of the scope of the invention
or of the intellectual property rights sought in the claims.
[0034] This detailed description refers by means of reference numerals to the appended drawings,
in which:
- Figure 1 is a cross section of an embodiment of a ventilation device according to this invention,
the first, second and third regulating valve each being in the position in which they
close off the ventilation channel;
- Figure 2 is a cross section of the embodiment of a ventilation device from Figure 1, the first,
second and third regulating valve each being in the position in which they allow a
maximum flow rate of air through the ventilation channel;
- Figure 3 schematically illustrates the operating principle of the coupled first and second
regulating valves; and
- Figure 4 schematically illustrates an alternative operating principle for coupled first and
second regulating valves.
[0035] The ventilation device (1) as depicted in Figures 1 and 2 is a ventilation device
(1) for the natural supply of air from the outside (3) to an internal space (2) or
for the discharge of air from the internal space (2) to the exterior (3). In Figure
2 the dot-dash arrow indicates the direction of the supply of air through the air
flow channel (4) of this ventilation device (1).
[0036] This ventilation device (1) further comprises a first, a second, a third and a fourth
regulating valve (5), (6), (7), (8) which are arranged so as to be able to rotate
or hinge in series, in such a way that during rotating or hinging of these regulating
valves (5), (6), (7), (8) the flow rate of air through the air flow channel (4) of
the ventilation device (1) is regulated.
[0037] The first and the second of these regulating valves (5), (6) are in this case mutually
mechanically coupled in such a way that during hinging or rotating of one of both
regulating valves (5) in a first direction with respect to the air flow channel (4)
the other of both regulating valves (6) hinges or rotates in the opposite direction
to this first direction with respect to the air flow channel (4).
[0038] The movement of these first and second regulating valves (5), (6) can for example
be mutually mechanically coupled by rotatingly connecting these regulating valves
(5), (6), at the level of a front plate of this ventilation device, to a drum which
is in turn rotatably arranged at the level of this front plate.
[0039] Other mechanical coupling mechanisms are conceivable. Coupling mechanisms of this
type can be implemented by a person skilled in the art and are not depicted in the
present document.
[0040] Figure 3 schematically presents the operating principle of these coupled regulating
valves (5), (6). The regulating valves (5), (6) from the embodiment of a ventilation
device according to this invention (1) from Figures 1 and 2 are represented by the
dot-dash line. The solid line presents regulating valves (5'), (6') which open and
close in the opposite direction. Figure 4 shows further possible arrangements of coupled
regulating valves (5"), (6") and (5"'), (6''') of this type. In each case the dashed
line presents the corresponding regulating valve in the closed position, while the
arrow in this regulating valve indicates the direction of opening thereof.
[0041] In the case of a difference in pressure over the air flow channel (4) from left to
right or vice versa, there will in each case be exerted on one of both regulating
valves a force which seeks to close this one regulating valve, while on the other
of both regulating valves there is exerted a force which seeks to open this other
regulating valve. As a result of the fact that the movement of both regulating valves
(5), (6) is mutually mechanically coupled, these opposite forces cancel each other
out and these regulating valves (5), (6) stabilize each other.
[0042] In the embodiment of a ventilation device (1) which was depicted in Figures 1 and
2, the movement of the third regulating valve (7) is furthermore also mechanically
coupled to the movement of these first and second regulating valves (5), (6). Coupling
mechanisms which may be used for this purpose have equally not been depicted in the
present document. The movement of this third regulating valve (7) could for example
be mechanically coupled to the movement of these first and second regulating valves
(5), (6) by connecting this third regulating valve (7), with the aid of a rod mechanism,
to the drum to which the first and second regulating valves (5), (6) are rotatably
fastened. This rod mechanism can also be incorporated into this ventilation device
(1) at the level of a front plate of the ventilation device (1). Other possible implementations
of the mechanical coupling of these three valves (5), (6), (7) are conceivable.
[0043] Furthermore, these first, second and third regulating valves (5), (6), (7) are hingeably
and releasably arranged with respect to the air flow channel (4) with the aid of clamps
(9). In order to releasably provide said regulating valves in the ventilation device
(1), for example for simple maintenance and/or cleaning of the ventilation device
(1), these regulating valves (5), (6), (7) should therefore furthermore be releasably
connected to the coupling mechanisms which mutually connect these regulating valves
(5), (6), (7).
[0044] The fourth regulating valve (8), which is hingeably and/or rotatably and/or pliably
arranged in the air flow channel (4), is a self-regulating valve which can adapt the
flow rate of air through the ventilation device (1) automatically (i.e. without activation
with the aid of a sensor or motor) on the basis of the difference in pressure over
the air flow channel (4). This fourth regulating valve (8) could equally be rotatably
or pliably arranged in the air flow channel (4). A combination of hingeable, rotatable
or pliable arrangement is also possible. Self-regulating valves (8) of this type are
already known in the art.
[0045] Furthermore, the ventilation device (1) from Figures 1 and 2 is provided with a removable
mosquito gauze (10), provided to prevent undesired insects from entering the space
(2).
[0046] Tests with the depicted ventilation device (1) from Figures 1 and 2, the profiles
(11) being made of PVC, the outer cap (12) being made of aluminium, the first and
second regulating valves (5), (6) being made of PVC and the third regulating valve
(7) being made of aluminium, indicate that this ventilation device has, at a difference
in temperature of 20 °C between the internal space (2) and the external space (3),
a U value of 1.5 W/(m
2K) and a temperature factor of 0.65.
[0047] A comparable ventilation device (1), the third regulating valve (7) being omitted,
resulted in a U value of 1.7 W/(m
2K).
[0048] Standard ventilation grates equipped with one regulating valve have a U value of
at least 3.0 W/(m
2K) and a temperature factor of less than 0.6.
[0049] Because of the three possibilities for closing-off using the first, second and third
regulating valve (5), (6), (7), the air-tightness of this ventilation device (1) is
also much better than a conventional ventilation device (1).
[0050] The embodiment provided hereinbefore of the ventilation device (1) does not form
any restriction. A large number of materials, designs, etc. may be considered for
producing ventilation devices (1) according to this invention. The profiles (11) may
equally be made of partially encasing aluminium profile parts between which insulating
material is attached. The first and second regulating valves (5), (6) can for example
be made completely from polyurethane in cases in which said regulating valves have
to be resistant to temperatures as low as -40 °C.
1. Ventilation device (1) for the natural supply of air or discharge of air, comprising
an air flow channel (4) wherein a first, a second and a third regulating valve (5),
(6), (7) are arranged so as to be able to rotate or hinge in series, in such a way
that during rotating or hinging of these regulating valves (5), (6) the flow rate
of air through this air flow channel (4) is regulated, characterized in that the hinging or rotating movement of at least two of the regulating valves (5), (6)
is mutually mechanically coupled.
2. Ventilation device (1) according to Claim 1, characterized in that the movement of the aforementioned at least two regulating valves (5), (6) is mutually
mechanically coupled in such a way that during hinging or rotating of one of both
regulating valves (5) in a first direction with respect to the air flow channel (4)
the other of both regulating valves (6) hinges or rotates in the opposite direction
to this first direction with respect to the air flow channel (4).
3. Ventilation device (1) according to Claim 1 or 2, characterized in that the movement of the aforementioned at least two regulating valves (5), (6) is mutually
mechanically coupled with the aid of a rod mechanism.
4. Ventilation device (1) according to Claim 2 or 3, characterized in that the movement of the aforementioned at least two regulating valves (5), (6) is mutually
mechanically coupled with the aid of a drum.
5. Ventilation device (1) according to Claim 4, characterized in that the movement of the aforementioned at least two regulating valves (5), (6) is mutually
mechanically coupled as a result of the fact that the two regulating valves (5), (6)
form part of the circumference of a hollow drum which is arranged so as to be able
to rotate in the ventilation channel (4).
6. Ventilation device (1) according to one of Claims 1 to 5 inclusive, characterized in that the movement of the first, the second and the third regulating valve (5), (6), (7)
is mutually mechanically coupled.
7. Ventilation device (1) according to one of the preceding claims, characterized in that at least two of the regulating valves (5), (6), (7) are embodied identically to one
another.
8. Ventilation device (1) according to one of the preceding claims, characterized in that at least one of the regulating valves (5), (6), (7) is releasably arranged.
9. Ventilation device (1) according to one of the preceding claims, characterized in that said ventilation device is provided with an actuator which can be used to activate
the movement of the regulating valves (5), (6), (7).
10. Ventilation device (1) according to one of the preceding claims, characterized in that at least a fourth regulating valve (8) is arranged in series with the first, the
second and the third regulating valve (5), (6), (7), in such a way that during rotating
and/or hinging of this first, second, third and fourth regulating valve (5), (6),
(7), (8) the flow rate of air through the air flow channel (4) is regulated, this
fourth regulating valve (8) being a self-regulating valve.