U.S. patent application number 14/427945 was filed with the patent office on 2015-08-13 for ventilation device comprising a first outlet and a second outlet.
This patent application is currently assigned to Swegon AB. The applicant listed for this patent is SWEGON AB. Invention is credited to Per- ke Larsson, Tomas Soderberg.
Application Number | 20150226449 14/427945 |
Document ID | / |
Family ID | 50278535 |
Filed Date | 2015-08-13 |
United States Patent
Application |
20150226449 |
Kind Code |
A1 |
Larsson; Per- ke ; et
al. |
August 13, 2015 |
Ventilation device comprising a first outlet and a second
outlet
Abstract
The present invention relates to a ventilation device (1)
comprising a first air duct (2) for air supply and a second air
duct (3) for air supply. The first air duct (2) comprises a first
outlet (4) for air flow and the second air duct (3) comprises a
second outlet (5) for air flow, where the first outlet (4) is
arranged to admit passage for a predefined amount of air per time
unit (F-i). The second outlet (5) comprises a controllable choke
device (6) that is arranged to either take a first position that
admits passage for a predefined amount of air per time unit (F3) or
a second position that does not admit passage of air. The
ventilation device (1) comprises a control unit (7) and at least
one detector (8, 9), where the control unit (7) is arranged to
control the controllable choke device (6) in dependence of input
data from said detector (8, 9) such that demand controlled
ventilation is obtained.
Inventors: |
Larsson; Per- ke; (Vastra
Amtervik, SE) ; Soderberg; Tomas; (Arvika,
SE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SWEGON AB |
Kvanum |
|
SE |
|
|
Assignee: |
Swegon AB
KVANUM
SE
|
Family ID: |
50278535 |
Appl. No.: |
14/427945 |
Filed: |
September 17, 2013 |
PCT Filed: |
September 17, 2013 |
PCT NO: |
PCT/SE2013/051085 |
371 Date: |
March 12, 2015 |
Current U.S.
Class: |
454/256 |
Current CPC
Class: |
Y02B 30/767 20130101;
F24F 11/76 20180101; F24F 2110/70 20180101; F24F 11/0001 20130101;
F24F 7/065 20130101; F24F 2120/12 20180101; F24F 13/06 20130101;
F24F 2120/14 20180101; F24F 11/74 20180101; F24F 2110/20 20180101;
F24F 2110/10 20180101; F24F 2110/00 20180101; Y02B 30/70 20130101;
F24F 3/0444 20130101; F24F 2110/50 20180101; F24F 11/30
20180101 |
International
Class: |
F24F 11/04 20060101
F24F011/04; F24F 11/053 20060101 F24F011/053 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 17, 2012 |
SE |
1251036-8 |
Claims
1-10. (canceled)
11. A ventilation device comprising a first air duct for air supply
and a second air duct for air supply, where the first air duct
comprises a first outlet for air flow and the second air duct
comprises a second outlet for air flow, where the first outlet is
arranged to admit passage for a predefined amount of air per time
unit, where the second outlet comprises a controllable choke device
that is arranged to either take a first position that admits
passage for a predefined amount of air per time unit or a second
position that does not admit passage of air, where the ventilation
device comprises a control unit and at least one detector, where
the control unit is arranged to control the controllable choke
device in dependence of input data from said detector such that
demand controlled ventilation is obtained, wherein the control unit
is arranged to control the choke device to shift between the first
position and the second position with a periodicity such that the
first position is taken during a first period of time and the
second position is taken during a second period of time, such that
a pulsating air flow is acquired at the second outlet.
12. The ventilation device according to claim 11, wherein each
detector is arranged to detect at least one of temperature, air
humidity, carbon dioxide content, motions and presence.
13. (canceled)
14. The ventilation device according to claim 13, wherein the
control unit is arranged to control the choke device such that the
first period of time is constant while the second period of time is
controllably variable, such that the first position is taken during
constant periods of time with controllably variable
periodicity.
15. The ventilation device according to claim 13, wherein the
control unit is arranged to control the choke device such that the
first period of time is controllably variable such that the first
position is taken during controllably variable periods of time with
a constant periodicity.
16. (canceled)
17. A method for controlling air supply via a first outlet for air
flow and a second outlet for air flow, where the first outlet
admits passage for a predefined amount of air per time unit,
wherein the method comprises the steps: detecting at least one
parameter in a space, where said parameter is related to the air
quality in the space; and controlling a choke device at the second
outlet in dependence of said detection such that the choke device
either takes a first position that admits passage for a predefined
amount of air per time unit or a second position that does not
admit passage of air such that a demand controlled ventilation is
obtained, where the control of the choke device results in a shift
between the first position and the second position with a
periodicity, such that the first position is taken during a first
period of time and the second position is taken during a second
period of time, such that a pulsating air flow is acquired at the
second outlet.
18. The method according to claim 16, wherein said detection refers
to at least one of temperature, air humidity, carbon dioxide
content, motions and presence.
19. (canceled)
20. The method according to claim 16, wherein the control of the
choke device results in that the first period of time is constant
while the second period of time is controllably variable, such that
the first position is taken during constant periods of time with a
controllably variable periodicity.
21. The method according to claim 16, wherein the control of the
choke device results in that the first period of time is
controllably variable such that the first position is taken during
controllably variable periods of time with a constant periodicity.
Description
TECHNICAL FIELD
[0001] The present invention relates to a ventilation device
comprising a first air duct for air supply and a second air duct
for air supply. The first air duct comprises a first outlet for air
flow and the second air duct comprises a second outlet for air
flow. The first outlet is arranged to admit passage for a
predefined amount of air per time unit.
[0002] The present invention also relates to a method for
controlling air supply via a first outlet for air flow and a second
outlet for air flow, where the first outlet admits passage for a
predefined amount of air per time unit.
BACKGROUND
[0003] During ventilation fresh air is in many cases supplied via
supply air diffusors, it may be one or more that are connected to a
main pipe, where supplied fresh air is brought into motion towards
the supply air diffusors via the main pipe by means of a fan
arrangement. It is sometimes desirable to control the flow of
supplied air in dependence of the present need. For example, a
conference room may sometimes be empty, and sometimes be more or
less occupied, such that different needs of air supply arise.
[0004] For example, one or more detectors for temperature or
motions may supply information regarding the present need of air
supply to a control unit that in turn may control the fan
arrangement in accordance with this need. Control according to
requirements for ventilation devices with a continuous ventilation
flow does, however, require advanced technology to measure and to
control. It may be problematic to optimize a ventilation product
for both large and small flows; small flows are often difficult to
measure.
[0005] There is therefore a desire for a ventilation device that is
demand controlled, and which lacks the above disadvantages.
DISCLOSURE OF THE INVENTION
[0006] The object of the present invention is to provide a
ventilation device that is demand controlled, and which is of a
less complicated nature than those that have been used until
present.
[0007] Said object is achieved by means of a ventilation device
comprising a first air duct for air supply and a second air duct
for air supply. The first air duct comprises a first outlet for air
flow and the second air duct comprises a second outlet for air
flow. The first outlet is arranged to admit passage for a
predefined amount of air per time unit. The second outlet comprises
a controllable choke device that is arranged to either take a first
position that admits passage for a predefined amount of air per
time unit or a second position that does not admit passage of air.
The ventilation device comprises a control unit and at least one
detector, where the control unit is arranged to control the
controllable choke device in dependence of input data from said
detector such that demand controlled ventilation is obtained.
[0008] Said object is also achieved by means of a method for
controlling air supply via a first outlet for air flow and a second
outlet for air flow, where the first outlet admits passage for a
predefined amount of air per time unit.
[0009] The method comprises the steps: detecting at least one
parameter in a space, where said parameter is related to the air
quality in the space; and controlling a choke device at the second
outlet in dependence of said detection such that the choke device
either takes a first position that admits passage for a predefined
amount of air per time unit, or a second position that does not
admit passage of air, such that demand controlled ventilation is
obtained.
[0010] According to an example each detector is arranged to detect
at least one of temperature, air humidity, carbon dioxide content,
motions and presence.
[0011] According to another example, the control unit is arranged
to control the choke device to shift between the first position and
the second position with a periodicity such that the first position
is taken during a first period of time and the second position is
taken during a second period of time, such that a pulsating air
flow is acquired at the second outlet.
[0012] Other examples are apparent from the dependent claims.
[0013] A number of advantages are obtained by means of the present
invention, for example: [0014] The ventilation device better
optimized for the flow which among other things relates to bring
along re-circulated air in a more controlled manner as well as for
lowering or avoiding noise or jarring ate certain flow velocities.
[0015] Few movable parts. [0016] Uncomplicated software control,
easily adjustable. [0017] Increased life span. [0018] Energy
efficient.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The present invention will now be described more in detail
with reference to the appended drawings, where:
[0020] FIG. 1 shows a schematic overview of a ventilation
device;
[0021] FIG. 2 shows a first graph for air flow versus time;
[0022] FIG. 3 shows a second graph for air flow versus time;
[0023] FIG. 4 shows a third graph for air flow versus time;
[0024] FIG. 5 shows a fourth graph for air flow versus time;
[0025] FIG. 6 shows a fifth graph for air flow versus time;
[0026] FIG. 7 shows a sixth graph for air flow versus time; and
[0027] FIG. 8 shows a flow chart for a method according to the
present invention.
DETAILED DESCRIPTION
[0028] FIG. 1 shows a ventilation device 1 that comprises a fan
arrangement 15 arranged to bring fresh air into motion, from an
inlet 10 to a main duct 11, and further from the main duct 11 to a
first air duct 2 and a second air duct 3 via a ramification 12. The
first air duct 2 comprises a first outlet 4 for air flow and the
second air duct 3 comprises a second outlet 5 for air flow, where
each outlet 4, 5 comprises a plurality of outlet apertures 13,
14.
[0029] With reference also to FIG. 2, showing a first graph 16 for
air flow versus time, the first outlet 4 is arranged to admit
passage for a predefined amount of air per time unit F.sub.1.
[0030] According to the present invention the second outlet 5
comprises a controllable choke device 6 that is arranged to either
take a first position that admits passage for a predefined amount
of air per time unit F.sub.3 or a second position that does not
admit passage of air, where the first graph 16 shows a state where
the choke device has taken the second position.
[0031] The ventilation device comprises a control unit 7, a first
detector 8 and a second detector 9, where the control unit 7 is
arranged to control the controllable choke device 6 in dependence
of input data from these detectors 8, 9 such that demand controlled
ventilation is obtained. By way of example, each detector 8, 9 is
arranged to detect at least one of temperature, air humidity,
motions, presence and air quality, such as carbon dioxide content.
The detectors are thus of an adapted kind, for example a detector
that is arranged to detect motions and/or presence in a previously
known manner may comprise a sensor for infrared radiation. It is
also conceivable that more sophisticated detectors are used, for
example camera arrangements that are adapted to detect the number
of persons in a room. At least indirectly, all detected parameters
are related to air quality, since for example a temperature rise,
an elevated air humidity, motions and presence indicate the
presence of one or more persons which is directly related to air
quality.
[0032] For example, when the detectors 8, 9 detect that a room is
empty, and that no extra ventilation is needed for another reason
than presence of persons such as for example elevated air humidity
or temperature, the choke device 6 is controlled to take the second
position, which is illustrated in FIG. 2. Then a desired base
ventilation is obtained in order to acquire a certain indoor
climate.
[0033] With reference to FIG. 1 and FIG. 3, a second graph for air
flow versus time is shown in FIG. 3 when the detectors 8, 9 have
detected that persons have entered a room. This may for example be
made by means of detection of movements and/or presence, an/or also
indirectly by detecting an elevated carbon dioxide content, which
in turn indicates a deteriorated air quality. Then the choke device
6 is controlled by the control device 7 to shift between the first
position and the second position with a periodicity T.sub..alpha.
such that the first position is taken during a first period of time
T.sub.1A and the second position is taken during a second period of
time T.sub.2A such that a pulsating air flow is obtained at the
second outlet 5. The period T.sub..alpha. of this periodicity
corresponds to the sum of the first period of time T.sub.1A and the
second period of time T.sub.2A, that is
T.sub..alpha.=T.sub.1A+T.sub.2A. The total maximum flow per time
unit F.sub.2 is obtained when the second position is taken and
corresponds to the sum of the flows F.sub.1, F.sub.3 via the
outlets 4, 5.
[0034] According to a first example, with reference also to FIG. 4
that shows a fourth graph for airflow versus time, if the detectors
8, 9 have detected that more air supply is needed, for example due
to the fact that more persons are detected in the room and/or that
the carbon dioxide content has been elevated, the choke device 6 is
controlled by the control unit 7 such that the first period of time
T.sub.1A is maintained constant while the second period of time is
decreased from a first value T.sub.2A to a second value T.sub.2B
such that the period of the periodicity is decreased from a first
period value T.sub..alpha. to a second period value T.sub..beta..
In this way, the time during which the choke device 6 is controlled
to take the first position is increased, resulting in an increased
air flow.
[0035] In this example, the first position is generally taken
during constant periods of time T.sub.1A and the second position
during controllably variable periods of time T.sub.2A, T.sub.2B,
such that a controllable periodicity T.sub..alpha., T.sub..beta.
for the first position is obtained. In this way, only the time
interval T.sub.2A, T.sub.2B when the second position is taken is
changed, that is when no air passage is admitted at the second
outlet 5, but no other parameters.
[0036] According to a second example, with reference to FIG. 1,
FIG. 3 and FIG. 5, where FIG. 5 shows a fourth graph 19 for airflow
versus time, if the detectors 8, 9 detect that more sir supply is
needed, the control unit 7 is instead arranged to control the choke
device 6 such that the first period of time is increased from a
first value T.sub.1A to a second value T.sub.1C while the second
period of time is correspondingly decreased from a first value
T.sub.2A to a second value T.sub.2C. In this way, the time during
which the choke device 6 is controlled to take the first position
is increased, resulting in an increased air flow.
[0037] Generally, the first position is taken during controllably
variable periods of time T.sub.1A, T.sub.1A with a constant
periodicity T.sub..alpha..
[0038] According to a third example, with reference also to FIG. 6,
where FIG. 6 shows a fifth graph 20 for airflow versus time, both
the first period of time has been changed from a first value
T.sub.1A to a second value T.sub.1C and the second period of time
has been changed from a first value T.sub.2A to a second value
T.sub.2C. Then the period of the periodicity has been changed from
a first value T.sub..alpha. to a second value T.sub.A.
[0039] According to the third example, the first period of time can
either be increased or decreased, and the second period of time can
also either be increased or decreased, independently of each
other.
[0040] All kinds of changes of pulse widths or pulse lengths in all
conceivable combinations may occur according to the present
invention. Naturally, where appropriate, the choke device 6 may be
controlled to take the first position during a longer time, which
is indicated in FIG. 7, shows a sixth graph 21 for airflow versus
time.
[0041] Suitably, the periods are controlled such that too long or
too short time intervals are avoided, for example the device may be
controlled such that intervals shorter than 1 minute or longer than
10 minutes are avoided except in those cases where the control
provides a signal indicating that it should be completely open or
completely closed.
[0042] With reference to FIG. 8, the present invention also relates
to a method for controlling air supply via a first outlet 4 for air
flow and a second outlet 5 for air flow, where the first outlet 4
admits passage for a predefined amount of air per time unit
F.sub.1.
[0043] The method comprises the steps: [0044] 23: detecting at
least one parameter in a space, where said parameter is related to
the air quality in the space; and [0045] 24: controlling a choke
device 6 at the second outlet 5 in dependence of said detection
such that the choke device 6 either takes a first position that
admits passage for a predefined amount of air per time unit
F.sub.3, or a second position that does not admit passage of air.
In this way, demand controlled ventilation is obtained.
[0046] The present invention is not limited to the above, but may
vary freely within the scope of the appended claims. For example,
the first outlet and the second outlet form an outlet pair 22, and
it is conceivable that the main duct comprises more ramifications
that lead to further outlet pairs of the same type. Such outlet
pairs may be present in the same room or different rooms, and in
the latter case it is desirable to have detectors in all current
rooms. A number of outlet pairs may also be integrated as one and
the same supply air diffusor, for example in the form of a
so-called cooling baffle.
[0047] The number of detectors in each room, and their different
types and functions may vary, but according to the present
invention there shall be at least one detector.
[0048] Fan arrangements, air ducts and chokes are of a well-known
kind, and are not further described here.
[0049] When it is stated that no air passage is admitted, this
should be interpreted as being within what is practically
obtainable in this field of technology; a certain amount of leakage
may therefore occur. Furthermore, the air flows are graphically
shown with sharp borders; practically there are softer transitions
between different positions where the different air flows may vary
somewhat over time due to leakage, wear, clogging of filters and
other sources of error. The graphical representations should
therefore be regarded as schematical description of the present
invention, and not as exact representations of reality.
[0050] At a ventilation device of this kind, a constant pressure in
the air ducts is desired. By also having knowledge about the
characteristics of the outlets 4, 5 with adherent outlet apertures
13, 14 one may obtain information regarding which flow that
currently passes the outlets 4, 5. With characteristics a so-called
k factor is referred to, which together with the duct pressure
provides the passed flow Q in liters per second according to the
formula:
Q=k {square root over (dP)}
where dP is the pressure difference between duct and
surroundings.
[0051] When the duct pressure is varied, a software-implemented
compensation of the flow may then be performed by changing the
length of the periods. By means of this knowledge of the
characteristics of the outlets and the current duct pressure, flow
measurement with special sensors may be avoided.
[0052] The control unit 7 is arranged to control the controllable
choke device 6 in dependence of input data from said detector 8, 9,
and it is also conceivable that time control may be used as a
complement. For example, knowledge about that a room is going to be
used at a certain time may be used to increase the ventilation a
certain time period before that time. In this case, the time
control works as a kind of indirect presence detection, and thus
the unit that regulates the time control can be regarded as a kind
of detector within the scope of the present invention. The detected
parameter in that case is time.
* * * * *