Technical field
[0001] The present invention discloses an improved wall hatch, specifically designed for
mechanical or forced ventilation systems. The proposed wall hatch is designed so it
can be mounted in an opening of a façade or wall of a building, and preferably used
for smoke and heat control ventilation systems.
[0002] The proposed mechanical wall hatch, suitable for both forced conventional ventilation
systems and smoke and fire safety systems, includes a quick release mechanism which
allows a flap or hatch of the wall hatch to open, at a predetermined angle in a pre-set
amount of time, according to fire safety regulations and standards, whilst simultaneously
complying with the output airflow of exhaust air required.
[0003] Furthermore, the mechanical wall hatch includes an air deflector, positioned in proximity
to the ventilation flap or hatch, which aids in guiding an airflow towards the exterior
of the building.
State of the Art
[0004] In the last few decades fire safety measures, including both active and passive fire
protection measures, have developed substantially due to increasingly stricter legislations
and regulations or standards when it comes to fire prevention in buildings. Due to
such a rapid evolution in fire safety measures, there is a wide range of smoke and
heat exhaust ventilation systems available in the market, categorized as active fire
safety measures.
[0005] This wide range of ventilation systems can be narrowed down to two main types: natural
smoke and heat ventilation systems and mechanical ventilation systems.
[0006] Natural smoke and heat ventilation systems create a natural airflow by opening airways
such as roof or skylight vents as well as windows or other ventilation units which
are part of a building façade or wall, using air flow dynamics enabling the smoke
and heat to be released outside the building.
[0007] On the other hand, mechanical (also commonly referred to as forced) smoke and heat
ventilation systems include the use of a fan to generate a forced airflow, extracting
and guiding the smoke and heat towards the airways of the building so it can be released
outside. The proposed invention, disclosed herein, belongs to mechanical or forced
ventilation systems and therefore must include a fan. Furthermore, the proposed invention
is designed specifically to be installed on a building façade or building wall opening
and can be used for either: conventional forced ventilation systems or smoke and heat
extraction systems, preferably said second application.
[0008] Ventilation systems may be further classified, according to their opening mechanism,
into either mechanically opened vents or drop-out vents.
[0009] Mechanically opened vents use mechanisms which are activated or driven through the
use of springs, pneumatic actuators, electric motors or a combination thereof, whereas
drop-out vents, which are usually single use vents, are those which, for example,
include a plastic layer that shrinks when exposed to heat and therefore exposes the
opening of the vent so that the heat and smoke can be released.
[0010] DE 4 407 276 B4, discloses a mechanism which may be driven manually or, preferably, automatically
using an electric actuator or driver, configured to open and close a ventilation flap
that is hinged to a frame of an exhaust vent which allow the vent to open under a
predetermined amount of time and at a maximum threshold angle, according to fire safety
regulations and standards. The electric actuator, such as a spindle motor, is arranged
inside a casing or housing structure, pivotally mounted on the frame of the exhaust
vent and includes a retractable elastic band or cord connected to an area of the ventilation
flap, so it may be opened automatically at a predetermined angle and closed.
[0011] European patent application
EP 2 685 041 A2 discloses a device for mounting a window into an opening of a wall which comprises
a premounting element, adjustably installed in said opening, made up of a frame onto
which a case of the window is installed, with an existing play between the frame of
the premounting element and the case of the window, so that the frame acts as a guiding
element for the case of the window, in order to position the window at an end or desired
position.
[0012] The present invention aims to solve issues in mechanical ventilation systems regarding
the turbulent flow which occurs when the forced airflow generated by a fan collides
with a surface of the hatch in an open position, reducing the speed at which the smoke
and heat is released. In order to overcome this, the present invention proposes the
use of guiding means which move sequentially with the driving or actuating means,
which open and close the hatch or vent at a predetermined angle, and aid in guiding
the smoke towards the exterior of the building, reducing airflow turbulence and therefore
increasing the speed at which heat and smoke is released towards the exterior of the
building.
Brief description of the invention
[0013] In order to overcome the issues raised previously, the present invention discloses
a mechanical smoke and heat ventilation system which has been designed to be installed
in a suitable opening of a façade or wall of a building.
[0014] The mechanical ventilation system comprises a substantially rectangular frame, which
is made up of at least an upper and a lower structural member and two lateral structural
members, with a hatch (also referred to sometimes as a flap) mechanically hinged to
the frame, an actuator which is used to open and close the hatch and a fan, allowing
smoke and heat to be guided towards the outside of the building.
[0015] The wall hatch, or wall flap, can be mechanically hinged to either one of the four
structural members which together form the frame. However, in a particular embodiment,
the hatch is preferably mechanically hinged to either one of the upper or the lower
structural members of the frame, according to the operational mode of the fan, in
which the fan can either generate a forced airflow into or outside the building when
the hatch is in an open position.
[0016] The hatch is opened or closed through the use of an actuator which is arranged inside
a protective housing or casing mounted on a portion of the frame.
[0017] In a particular embodiment, the protective housing containing the actuator is pivotally
mounted in a transversal central portion of the frame between both lateral structural
members of the frame, wherein each end of the housing is fixed to each one of the
lateral structural members using mechanical fasteners, such as screws, so that the
housing pivots around a longitudinal axis of the housing, transversal to the frame.
[0018] However, this particular arrangement of the actuator and its housing is non-limiting
and other alternative arrangements of the actuator with regards to the frame, known
in the current state of the art should be deemed as equivalent and obvious to a person
skilled in the art.
[0019] The actuator used to modify the position of the hatch is preferably a linear actuator
which is selected from, but not limited to, a group comprising: an electric chain
actuator, a rack and pinion actuator, a spindle actuator, a folding arm actuator,
a pneumatic cylinder or a motor reducer with an anti-side bow chain, amongst others.
[0020] In a particular embodiment of the present invention, the actuator is preferably an
electric chain actuator which opens and closes the hatch through the use of a retractable
element, for this particular embodiment a chain, which moves through an opening of
the housing. A distal end of the retractable element is attached to a suitable fixing
point, such as a hook, located on an interior surface of the hatch, so that the hatch
may be either opened or closed when the actuator is operative by increasing or decreasing
the length of the chain.
[0021] In other literature, the term "drive" can be used in lieu of the term "actuator"
used herein and should be understood as being synonymous.
[0022] Mechanical ventilation systems use a fan to generate forced ventilation of an interior
space of a building and/or to remove smoke and heat from the interior of a building,
when a fire has originated, wherein the fan generates a forced flow of air towards
open airways of the building, such as the present invention. However, when this flow
of air, as well as the smoke and heat, collide against the hatch, before being released
to the exterior of the building, the flow of air becomes turbulent which in turn reduces
the speed at which smoke is released.
[0023] In order to overcome the problems associated with the appearance of a turbulent flow
of air, the proposed ventilation system further includes a deflector which is mechanically
fastened to the frame in such a manner that it can pivot in an opposite direction
to that of the hatch, in response to the opening and closing of the hatch.
[0024] The mechanical elements or fasteners used in order to attach the deflector to the
frame, are placed on one or both of the structural lateral members of the frame and,
in a particular embodiment, consist of a first attachment point fixed directly to
the deflector which can rotate or pivot, and a second attachment point which comprises
a lever mechanism connecting said first attachment point and the deflector, allowing
the deflector to pivot and move in time with the opening and closing of the ventilation
flap or hatch, although in an opposite direction. Therefore, the deflector is tilted
at a given angle according to the position of the hatch.
[0025] The deflector is positioned in an area of the frame where the flow of air, smoke
and/or heat generates the greatest turbulence upon impact with an inner surface of
the hatch, allowing the deflector to direct the forced flow of air, as well as smoke
and/or heat, towards the exterior of the building at a given opening angle of the
hatch, according to fire safety regulations and standards, if the forced mechanical
ventilation system, disclosed herein, is used for such applications.
[0026] In certain embodiments, the deflector may include a plurality of guiding elements,
such as blades, ailerons, flaps, or other suitable elements which are usually slender
flat components that are made of a suitable material which can withstand high temperatures.
These guiding elements are preferably arranged parallel to one another and separated
equidistantly. Furthermore, these guiding elements may be arranged on the deflector
at a predetermined angle.
[0027] The mechanical ventilation system disclosed herein further comprises an adjustable
external frame which is mounted in a suitable cavity or opening of a building wall
or façade, so that the frame, to which the hatch and deflector are mounted, can be
mounted inside this adjustable external frame in a slidably adjustable configuration.
[0028] Therefore, the frame is slidably mounted inside the adjustable external frame using
mechanical fasteners, guiding rails, grooves, releasable locking mechanisms or a combination
thereof, in order to obtain a correct alignment between the frame and hatch with the
building wall or fagade.
[0029] It should be noted that the hatch is limited in an embodiment to a maximum angular
opening, in which said maximum angle is set between 50º and 60º, and the actuator
which modifies the position of the hatch must open the hatch up to said maximum angle
in a pre-set time. The maximum angular opening is determined according to certain
characteristics of the mechanical ventilation system, such as: the size of the hatch
and the maximum airflow generated by the fan, although this angle must never be smaller
than the minimum angle defined by suitable safety standards and regulations according
to the use of the disclosed forced ventilation system.
[0030] It will be understood that references to geometric position, such as parallel, perpendicular,
tangent, etc. allow deviations up to ± 5° from the theoretical position defined by
this nomenclature.
[0031] It will also be understood that any range of values given may not be optimal in extreme
values and may require adaptations of the invention to these extreme values are applicable,
such adaptations being within reach of a skilled person.
[0032] Other features of the invention appear from the following detailed description of
an embodiment.
Brief description of the Figures
[0033] The foregoing and other advantages and features will be more fully understood from
the following detailed description of an embodiment with reference to the accompanying
drawings, to be taken in an illustrative and not limitative, in which:
- FIG. 1 illustrates the different components which, when assembled together, comprise the
forced mechanical ventilation system disclosed herein; and
- FIG. 1A illustrates a detailed view of a hinge and lever mechanism, as seen in FIG. 1, which
enable a wall hatch and a deflector to move synergistically, according to the present
invention.
Detailed description of an embodiment
[0034] The foregoing and other advantages and features will be more fully understood from
the following detailed description of an embodiment with reference to the accompanying
drawings, to be taken in an illustrative and non-limitative manner, in which:
FIG. 1 shows a forced mechanical ventilation system 1, according to the present invention,
conceived for installation in an opening of a building wall or façade, comprising
a frame 2, a wall hatch (or wall flap) 3, an actuator 4, a deflector 5, an adjustable
external frame 6 and, optionally, an embellishment 7.
[0035] The wall hatch 3 is mechanically hinged to said frame 2 by means of a hinge mechanism
8 (as seen in Fig. 1A), which, according to this particular embodiment, mechanically
fastens the wall hatch 3 to a lower transversal structural member 2b of the frame
2.
[0036] The actuator 4, although referenced in this figure, is not shown as it is located
inside a housing 40, which is pivotally fastened to opposite extending members 20
of lateral structural members 2c of frame 2. This allows the housing 40 of the actuator
4 to tilt or rotate in a limited manner around a longitudinal axis, which is parallel
to the upper and lower structural members 2a, 2b of frame 2, according to the position
of the wall hatch 3.
[0037] The housing 40 of the actuator 4, has an opening (not shown in these Figs.) through
which a retractable element, such as a chain or a cord, exits and having one of its
ends fastened to a hook 30 (or other suitable fixation means) located in an inner
surface of the wall hatch 3. Therefore, when the actuator 4 is in use, it opens and
closes the wall hatch 3, by extending or retracting said retractable element, as know
in the art according to
DE 4 407 276.
[0038] The deflector 5, previously mentioned, used in the forced mechanical ventilation
system 1 comprises a plurality of guiding elements 50 used to redirect a forced airflow
generated by a fan towards an opening defined by an angle of the wall hatch 3 in an
open position.
[0039] The deflector 5 is mechanically fastened to the lateral structural members 2c of
frame 2 by means of a lever mechanism 9, which is also connected to the hinge mechanism
8 used to fasten the wall hatch 3 to frame 2, so that when the wall hatch 3 is opened
by means of actuator 4, the deflector 5 tilts in an opposite direction so that the
forced airflow generated by the fan is redirected instead of colliding directly against
an inner surface of the wall hatch 3, avoiding the generation of turbulent conditions
which difficult ventilation.
[0040] Finally, frame 2 of the forced mechanical ventilation system 1 is installed onto
the adjustable external frame 6 which is mounted in a cavity or suitable opening of
a building wall or façade.
[0041] The frame 2 is installed inside the adjustable external frame 6 in such a manner,
that it is slidably adjustable using either one of mechanical fasteners, guiding rails,
releasable locking mechanisms or a combination thereof, in order to position the frame
2 adequately with regards to adjustable external frame so that the wall hatch 3 can
be opened and closed properly, enabling the forced mechanical ventilation system 1
to perform correctly.
[0042] For this particular embodiment, the forced mechanical ventilation system 1 includes
an embellishment 7. The embellishment 7 has a plurality of tabs 70 which are inserted
into openings or slots of both the frame 2 and the external adjustable frame 6, wherein
the slots in both frames, 2, 6 are preferably aligned. By inserting said plurality
of tabs 70 into the slots, the embellishment 7 is retained and placed against frame
2, covering it.
[0043] FIG. 1A is detailed, large-scale, representation of both the hinge mechanism 8 and the lever
mechanism 9 used to move both the wall hatch 3 and the deflector 5, in opposite directions,
as seen in
FIG. 1 with reference A.
[0044] It will be understood that various parts of one embodiment of the invention can be
freely combined with parts described in other embodiments, even being said combination
not explicitly described, provided there is no harm in such combination.
1. A forced mechanical ventilation system (1), for installation on a building wall, comprising:
- a frame (2),
- a wall hatch (3) mechanically hinged to either an upper structural member (2a) or
a lower structural member (2b) of said frame (2),
- an actuator (4) arranged inside a housing (40), said housing (40) being pivotally
mounted on a portion of the frame (2) so that it pivots around a longitudinal axis
of the housing (40), transversal to the frame (2), and
- a fan,
wherein said actuator (4) opens and closes said hatch (3) through the use of a retractable
element exiting the housing (40),
characterised in that it further comprises a deflector (5) fastened to the frame (2) and configured to
pivot in an opposite direction to that of the hatch (3) in response to the opening
and closing of the hatch (3) and configured to direct an airflow towards an exterior
of the building at a given angle defined by the opening of the hatch (3),
wherein said deflector (5) is positioned in an area of the frame (2) where said airflow
generates the greatest turbulence due to direction of impact with an inner surface
of the hatch (3), and
wherein the deflector (5) comprises a plurality of guiding elements (50).
2. Forced mechanical ventilation system (1) according to claim 1, wherein the deflector
(5) is tilted at a given angle according to the position of the hatch (3).
3. Forced mechanical ventilation system (1) according to claim 1 or 2, wherein the deflector
(5) is pivoted by a lever mechanism (9) connected to the hinging mechanism (8) of
the hatch (3).
4. Forced mechanical ventilation system (1) according to claim 1, further comprising
an adjustable external frame (6) mounted in a cavity of said building wall.
5. Forced mechanical ventilation system (1) according to claim 4, wherein the frame (2)
is mounted on an interior of the adjustable external frame (6).
6. Forced mechanical ventilation system (1) according to claim 5, wherein the frame (2)
is slidably adjustable inside the adjustable external frame (6) using mechanical fasteners,
guiding rails, releasable locking mechanisms or a combination thereof.
7. Forced mechanical ventilation system (1) according to claim 1, wherein the housing
(40) of the actuator (4) is mounted on a central portion of the frame (2) and fixed
to each one of a lateral structural member of the frame (2).
8. Forced mechanical ventilation system (1) according to claim 1, wherein the actuator
(4) is a linear actuator selected from a group comprising: an electric chain actuator,
a rack and pinion actuator, a spindle actuator, a folding arm actuator, a pneumatic
cylinder or a motor reducer with an anti-side bow chain.
9. Forced mechanical ventilation system (1) according to claim 1, wherein the actuator
(4) is an electric chain actuator.
10. Forced mechanical ventilation system (1) according to claim 1, wherein the hatch (3)
is limited to a maximum angular opening between 50º and 60º according to the size
of the hatch (3) and the maximum airflow generated by the fan.