FI20195005A1 - A damper - Google Patents

A damper Download PDF

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Publication number
FI20195005A1
FI20195005A1 FI20195005A FI20195005A FI20195005A1 FI 20195005 A1 FI20195005 A1 FI 20195005A1 FI 20195005 A FI20195005 A FI 20195005A FI 20195005 A FI20195005 A FI 20195005A FI 20195005 A1 FI20195005 A1 FI 20195005A1
Authority
FI
Finland
Prior art keywords
damper
duct
state
location
flow
Prior art date
Application number
FI20195005A
Other languages
Finnish (fi)
Swedish (sv)
Other versions
FI128811B (en
Inventor
Lars-Eric Lind
Original Assignee
Ilmastointimittaus Lind Oy
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Filing date
Publication date
Application filed by Ilmastointimittaus Lind Oy filed Critical Ilmastointimittaus Lind Oy
Priority to FI20195005A priority Critical patent/FI128811B/en
Publication of FI20195005A1 publication Critical patent/FI20195005A1/en
Application granted granted Critical
Publication of FI128811B publication Critical patent/FI128811B/en

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/08Air-flow control members, e.g. louvres, grilles, flaps or guide plates
    • F24F13/10Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers
    • F24F13/14Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre
    • F24F13/1486Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers built up of tilting members, e.g. louvre characterised by bearings, pivots or hinges
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16KVALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K1/00Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces
    • F16K1/16Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces with pivoted closure-members
    • F16K1/18Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces with pivoted closure-members with pivoted discs or flaps
    • F16K1/22Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces with pivoted closure-members with pivoted discs or flaps with axis of rotation crossing the valve member, e.g. butterfly valves
    • F16K1/221Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces with pivoted closure-members with pivoted discs or flaps with axis of rotation crossing the valve member, e.g. butterfly valves specially adapted operating means therefor
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16KVALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K29/00Arrangements for movement of valve members other than for opening and closing the valve, e.g. for grinding-in, for preventing sticking

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Duct Arrangements (AREA)

Abstract

A damper (300) for use in an arrangement for adjusting flow of a duct (104), wherein the damper is substantially rod-shaped in a first state, and in a second state, extending means (310) are extended from the rod shape, and extension elements (312) attached thereto are also simultaneously extended from a rod body (302), the second state leading to the damper embodying a shape of predetermined form.

Description

TECHNICAL FIELD OF THE INVENTION
The invention is in general related to heating, ventilation, and air conditioning (HVAC) systems and components used in HVAC systems.
More specifically, the invention is related to a damper for use in an arrangement for adjusting flow of a duct for an HVAC system.
BACKGROUND OF THE INVENTION
Most buildings usually incorporate some form of HVAC system involving ducts that requires maintenance and adjustment. The ducts should be io cleaned and flows and/or pressures within the ducts should be monitored and adjusted regularly in order to ensure that the system is operating as intended.
The current means for testing, adjusting, and balancing (TAB) of HVAC systems are slow and expensive. Performing TAB involves placement of is sensors at different locations in the HVAC system and using measurements of the sensors to determine if adjustments should be made to components of the HVAC system such as dampers, valves, fans, or pumps in order to maintain the system in a desired state. The desired state may, for example involve target flow parameter values, such as target pressures or volume 20 flow rates at certain locations, assigned by a mechanical engineer involved in the design of the HVAC system. Usually the TAB process involves many stages as adjustments and analysis of sensor measurement values are repeatedly conducted until the desired state is achieved, making the process time-consuming and laborious.
Preliminary adjustments of the components may be calculated using floor plans (which indicate configurations of ducts), target values for flow parameters in certain locations of the ducts, and information regarding components. Locations of components should be specified, along with information relating to component adjustments and flow parameters. For 30 example, in the case of a valve, the information may specify an amount of fluid that may pass through the valve at a certain adjustment (i.e. at a certain state of openness).
20195005 prh 04-01- 2019
A TAB technician typically makes preliminary adjustments of components in a duct and then performs measurement of flow parameters through sensors that are placed in the duct, after which adjustments may have to be updated if it is determined through measurements made by the sensors that the flow 5 parameters are not at target values. The technician may have to perform many rounds of adjustment and measurement, and travel along a duct configuration many times in order to read sensor measurements giving flow parameters and to perform the adjustments and once again inspect sensor measurement readings after performing changes to the adjustments of io components.
A further difficulty that is often faced while conducting TAB of HVAC systems is that the floor plans of HVAC systems of a building do not often match the actual layout of the system. The plans may have changed without updating of the documents or deviation from the plans may have occurred is during construction. The HVAC system parameters, such as adjustment parameters of components, may be determined according to the erroneous floor plans, leading to errors and difficulties in maintenance. As preliminary adjustments of the components to be installed in an HVAC system are conventionally computed with respect to the floor plans, they may be 20 substantially incorrect if floor plans are not up to date. Also, calculated adjustment parameters cannot take into account e.g. leaks in the duct configuration.
While performing TAB on an HVAC system, components such as dampers may have to be installed after the duct configuration and HVAC system has 25 already been designed and built. The ducts may, for instance, incorporate a fire prevention material, which might have to be removed in order to install a damper, in addition to possible dismantling of at least a portion of the duct configuration. This process may be strenuous, time-consuming, and lead to excessive material consumption.
In another aspect, reporting of the work done on HVAC systems to clients, including e.g. cleaning of the ducts, involves a separate work step that is error-prone and customers may have no way of confirming that the reported work was in fact carried out. Changes occurring in the HVAC system may also not be detected, which may lead to monetary losses for example in the 35 case of leaks, as well as health hazards related to mold formation, for instance.
20195005 prh 04-01- 2019
SUMMARY OF THE INVENTION
An object of the invention is to alleviate at least some of the problems relating to the known prior art. Especially the object of the invention is to provide a damper for use in an arrangement for adjusting flow of a duct, 5 wherein the damper is substantially rod-shaped in a first state, and in a second state, extending means are extended from the rod shape, and extension elements attached thereto are also simultaneously extended from a rod body, the second state leading to the damper embodying a shape of predetermined form.
io In one embodiment, the damper may be configured to be inserted into a hole in a duct, and the damper may additionally comprise a guiding element that is configured to reside on the outside of the duct. Transformation of the damper from the first state to the second state may then be brought about through manipulation of the guiding element.
is In some embodiments, pushing on the guiding element may lead to the transformation from the first state to the second state and pulling on the guiding element may lead to transformation from the second state to the first state.
In an embodiment, in the second state, the extension elements may form a 20 shape with a surface area that is essentially circular, so that the shape may be essentially similar to the inner dimensions of a duct that the damper may be configured to be inserted into.
The extending means may in an embodiment be wire or cable and the extension elements may be essentially flat elements that are configured to 25 be extended by the attached extending means.
A damper may be essentially protractible and additionally comprise a rod extender portion that may be used to enable extending of the extending means from the rod body, the rod extender portion being visible in the first state and contained inside the rod body in the second state.
An extension element of one embodiment of a damper according to the invention may be connected to one or more adjacent extension elements through one or more hinges or flexible joints.
20195005 prh 04-01- 2019
An embodiment of a damper may be configured to be secured to a duct and the damper may be adjusted by further manipulation of the guiding element. The further manipulation may be rotation of the guiding element, which may lead to rotation of the rod body and the attached extension elements, 5 wherein the rotating and consequential positioning of the damper with respect to a duct may enable control of an amount of fluid being able to pass the damper per time unit.
In an embodiment, a damper may be configured to be inserted into a hole in a duct wall and additionally comprise a sealing element, wherein the sealing io element may be configured to seal the hole. A damper may additionally comprise a fixing panel located adjacent to the sealing element to secure the damper to the duct.
In one embodiment, an arrangement may be provided for determining adjustment parameters for at least two components of an HVAC system is comprising at least one duct, wherein the arrangement comprises at least one processor that is configured to receive information regarding dimensions and/or layout of said at least one duct of the HVAC system and receive a first target value for at least one first flow parameter in a first duct location corresponding to the location of a first component comprised in the 20 HVAC system. The processor may additionally be configured to receive at least a first measured value for at least one second flow parameter in at least one first measuring location of the duct and receive location information regarding the at least two components, wherein the location information is indicative of at least a relative location of the at least two 25 components and their location with respect to the at least one duct. Further, the processor may be configured to resolve a first determined value for the second flow parameter in the first duct location utilizing the received first measured value for a second flow parameter and the received location information and then determine a first flow factor for the first component 30 utilizing the received first target value for the first flow parameter in the first duct location and the first determined value for the second flow parameter in the first duct location, after which the processor may determine a first adjustment parameter for the first component through the first determined flow factor. The processor may be configured to additionally receive a 35 second target value for at least one first flow parameter in a second duct location corresponding to the location of a second component comprised in
20195005 prh 04-01- 2019 the HVAC system and resolve a second determined value for the second flow parameter in the second duct location utilizing the received first measured value for the second flow parameter and the received location information. In addition, the processor may be configured to determine a 5 second flow factor for the second component utilizing the received second target value for the first flow parameter in the second duct location and the second determined value for the second flow parameter in the second duct location, after which it may determine a second adjustment parameter for the second component through the determined second flow factor for the io second component
In advantageous embodiments, the arrangement is configured to receive information regarding the layout and/or dimensions of a duct configuration. The layout may refer to turns, bends, and/or junctions in the duct configuration. Dimensions may refer to a shape, diameter, and/or length.
is In an embodiment, the information on the duct system is obtained through an information gathering device. The device may be configured to meneuver in a duct. The maneuvering may be actuated by a user of the arrangement, e.g. by the user pushing the device through the duct, or the device may be configured to move automatically.
The information received regarding a duct configuration, especially in the case that it is received through an information gathering device, may differ from the information given in the floor plans of a building, ensuring that the TAB process may be conducted properly taking into account the actual configuration of the duct or ducts, and time is not lost due to this issue.
The information gathering device may gather information through various sensors, the sensors being configured to obtain information regarding the duct configuration that is to be received by the arrangement.
The information gathering device may in advantageous embodiments comprise means for cleaning a duct, such as one or more brushes, or be 30 adapted to enable cleaning of a duct through coupling with an external device, such as a device comprising a brush, and be utilized prior to the TAB process to firstly clean the duct or ducts, while simultaneously measuring the dimensions and/or layout of the one or more ducts.
In some embodiments, the information gathering device may also obtain
20195005 prh 04-01- 2019 location information regarding one or more components and this information may then be received by the processor. Location information may be obtained as a separate process or simultaneously to cleaning and/or gathering of information regarding the duct.
The flow parameters may refer e.g. to pressures or fluid volume flow rates. For example, the first flow parameter for which target values are received may be air volume flow rate and the second flow parameter for which a measured value is received may be pressure.
In an embodiment of the present invention, an arrangement may receive an io HVAC plan comprising information that may e.g. be determined by a designer of the HVAC system. This information may comprise information regarding a planned or intended layout of a duct configuration, planned locations of one or more components, the type of the one or more components, and/or one or more target values of flow parameters. An is HVAC plan may for instance be received as a DWG file.
The components utilized in the HVAC system may comprise e.g. valves and/or dampers. A flow factor may be a factor that describes the relationship between the pressure drop across a component and the corresponding flow rate. Adjustment parameters may refer to e.g. adjustments of positions into 20 which components such as valves or dampers are set, i.e., how “open” they are. A certain adjustment may correspond to a value for a flow factor. Flow factors may be available for different adjustments of a component and for different components.
In some embodiments, an information gathering device may obtain 25 identification information regarding a component. If the information gathering device maneuvers in the duct, the device may comprise sensors or other means for detection of a component and the arrangement may be configured to identify the component.
Using a received measured value for a flow parameter in a measuring 30 location of the duct, the arrangement may resolve a determined value for the flow parameter in another duct location. This may be done utilizing flow parameter data regarding the second flow parameter that may indicate how the second flow parameter changes while traversing through a duct with certain dimensions and/or layout. In some embodiments the flow parameter
20195005 prh 04-01- 2019 data is also obtained by the processor.
A measured value may be received through a sensor located in the duct. In an advantageous embodiment, the sensor may wirelessly communicate information, comprising at least measured values, to the processor.
Adjustment parameters for the components may be determined through the determined flow factors and adjustment data that may in an embodiment be obtained by an arrangement. The adjustment data may comprise data relating a flow factor to an adjustment parameter.
The arrangement may be used for TAB of an HVAC system for a particular io duct configuration. This provides an advantage over the known prior art, as adjustment parameters for components in an HVAC system may be determined according to the actual duct configuration instead of possibly inaccurate floor plans.
In some embodiments, the processor may receive a plurality of measured is values for a flow parameter. For example, a measured value for the second flow parameter in a duct location corresponding to a component may in an embodiment be received by the arrangement. Using the measured values, an arrangement may resolve one or more updated determined values for at least one flow parameter in one or more duct locations. Then, the 20 arrangement may determine updated adjustment parameters for one or more components.
If adjustment parameters are determined using a first measured value for a second flow parameter at a first measuring location which is not a duct location corresponding to a component, a second measured value may be 25 obtained at a second measuring location, wherein the second measuring location corresponds to the location of a component, e.g. the first duct location corresponding to the location of a first component. The second measured value for the second flow parameter may indicate that the first determined value for the second flow parameter at the first duct location is 30 not achieved in reality, e.g. due to a leak. The arrangement may then determine an updated first flow factor and an updated first adjustment parameter for the first component. Then, an updated second determined value for the second flow parameter at the second duct location (the location of the second component) may be resolved, and accordingly, an
20195005 prh 04-01- 2019 updated second flow factor and an updated second adjustment parameter may be determined for the second component.
In embodiments where the arrangement is utilized to determine adjustment parameters for more than two components, the procedures explained above 5 may be used to resolve third, fourth, etc. determined second flow parameters at third, fourth, etc. duct locations (corresponding to the locations of a third, fourth, etc. component) and third, fourth, etc. flow factors and adjustment parameters may be determined for the third, fourth, etc. components.
io The arrangement may provide an output to a user indicative of at least one determined adjustment parameter. The output may be communicated to the user through a user interface on a user device. Advantageously, adjustment parameters are communicated to the user, such as a TAB technician, along with one or more measured values for one or more flow parameters.
is In an exemplary use scenario, a first measured value for a second flow parameter in a first measuring location may be received, and using said first measured value, adjustment parameters may be determined for two or more components comprised in an HVAC system. A TAB technician may for example then adjust a first component according to the first determined 20 adjustment parameter. He/she may then install a sensor at the first duct location corresponding to the location of the first component and thus receive a second measured value for the second flow parameter. The arrangement may then possibly determine an updated first adjustment parameter that is different from the first determined adjustment parameter.
The updated first adjustment parameter may be determined through first determining an updated first flow factor based on the second measured value for the second flow parameter at the firs duct location. Second, third, etc. possible updated adjustment parameters may also be determined after the second measured value is received. The technician may then move to the second component location, perform the adjustment according to the second updated adjustment parameter and once again install a sensor at the second duct location, and receive a third measured value for a second flow parameter at the second duct location. As disclosed above, the third measured value may be used to determine new updated adjustment parameters for any of the components comprised in the HVAC system.
20195005 prh 04-01- 2019
In embodiments of the invention, measured values may be taken at any measuring locations. Measuring locations may reside at component locations. Measured values may be received from all component locations or one or more component locations or measuring locations that do not 5 correspond to component locations.
In some embodiments, sensors may be readily installed in selected measuring locations.
Utilizing the arrangement, a TAB technician may not have to perform adjustment of components through trial and error. Traveling back and forth io along a duct to detect sensor readings may not be required, as the arrangement may inform a user of real-time flow parameters in locations where sensors are placed. The arrangement may also indicate if a certain component’s adjustment should be updated, and after a technician has performed the change in adjustment, he/she may observe through the user is interface the resulting change in flow parameters measured by the sensors.
In an embodiment, a component comprised in an arrangement for adjusting flow in a duct may be a protractible damper, where the damper is adapted to be easily incorporated with a duct. Dismantling of the duct is advantageously not required, saving time and amount of necessary labor, in 20 addition to possible material reductions that may be induced. Removing a protractible damper which is adapted to be easily incorporated with a duct is also conducted with ease.
In addition, the time required to conduct a TAB process may be substantially reduced through the arrangement, because possibly erroneous floor plans 25 are not utilized to make preliminary adjustments. A technician also does not have to perform many rounds of adjustments and analysis of outputs of sensors.
In some embodiments, the arrangement may conduct adjustments of the components automatically, which may reduce time and costs of 30 maintenance of HVAC systems.
In addition to aiding in TAB processes, an arrangement may continually monitor the state of an HVAC system and conduct procedures in particular circumstances. The circumstances may for instance involve changes in the measurements made by a sensor. In some embodiments, a sensor may be
20195005 prh 04-01- 2019 configured to detect changes that may be indicative of mold. Sensor readings, or measured values, may also e.g. be indicative of a leak in the system. The procedures to be conducted may include alerting a user entity of the arrangement in some way. In some embodiments, the procedures 5 may include giving instructions to a user entity. Abnormalities in system behaviour and other issues including possible mold may be taken care of more efficiently than using the current methods.
An arrangement may record all the procedures that have been carried out during a possible TAB process or HVAC design process that may involve io cleaning of ducts. This information may be made readily available to a possible client, which omits the work step of reporting conducted work and also provides a work report which may be trusted by a client.
In an exemplary embodiment, if cleaning is performed via an information gathering device, a client may view through a possibly provided user is interface which ducts have in fact been cleaned, and does not have to rely on information received from a source such as a contractor that has performed the cleaning. The cleaning process, as well as any other part of the TAB process may in an embodiment be observed essentially in real time through a user interface, facilitating also swifter and more accessible 20 communication between e.g. a client and a TAB contractor as compared to conventional means such email or telephone. The need for separate reporting to a client may be eliminated. In embodiments where the information gathering device comprises a camera, footage of the duct may be captured. This footage may also be used to verify that cleaning has been 25 performed and the performance of the cleaning may also be evaluated.
Information concerning a duct configuration may also be automatically saved to a CAD-program, which may eliminate a need for redrawing floor plans. Modified plans may be available for printing immediately.
Future communication between a TAB contractor or company that has 30 installed the arrangement or any instance that shall possibly execute cleaning, TAB, or other procedures related to the HVAC system and a client or owner of the HVAC system may be facilitated and improved through utilization of an embodiment of the present invention. In some embodiments, information regarding the HVAC system may be 35 automatically reported to for instance the TAB contractor. The TAB
20195005 prh 04-01- 2019 contractor may then contact the client when needed or desired and suggest recommended procedures.
The arrangement may also be used to test an HVAC system. A user may adjust a component, such as a vent, and observe the effects on the HVAC 5 system.
The exemplary embodiments presented in this text are not to be interpreted to pose limitations to the applicability of the appended claims. The verb to comprise is used in this text as an open limitation that does not exclude the existence of unrecited features. The features recited in depending claims io are mutually freely combinable unless otherwise explicitly stated.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from is the following description of specific example embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Next the invention will be described in greater detail with reference to exemplary embodiments in accordance with the accompanying drawings, in 20 which:
Figure 1 illustrates an exemplary arrangement according to one embodiment of the invention,
Figure 2 shows an exemplary information gathering device according to one embodiment of the invention,
Figure 3 gives an exemplary protractible damper according to one embodiment of the invention, and
Figure 4 shows the steps taken in a method according to an embodiment of the invention.
20195005 prh 04-01- 2019
DETAILED DESCRIPTION
Figure 1 shows an exemplary arrangement 100 according to an embodiment of the invention. The arrangement 100 comprises at least one processor 102 configured to receive information regarding the layout and/or 5 dimensions of at least one duct 104 comprised in an HVAC system.
In an embodiment, the information regarding layout and/or dimensions of the at least one duct 104 is obtained through an information gathering device 106.
In yet another embodiment, the information regarding layout and/or io dimensions of the at least one duct 104 is obtained through an information gathering device 106, while an information gathering device 106 simultaneously cleans or enables cleaning of a duct 104.
The processor 102 also receives a first target value for at least one first flow parameter, such as a volume flow rate, at a first duct location corresponding is to the location of a first component 112 comprised in the HVAC system. The aforementioned target value may in some embodiments be defined by a user of the arrangement 100, and may optionally be received through the use of a user device 108 comprising a user interface 110.
Target values for one or more flow parameters may also be received e.g. 20 through a separate file such as a DWG file indicating planned characteristics of the HVAC system.
A first measured value for a second flow parameter, such as pressure, in a first measuring location is also received.
One or more measured values may be obtained through one or more 25 sensors 116 located in a duct 104. A measured value may be communicated to the processor 102 through a user device 108 or in some embodiments a sensor 116 may automatically communicate a measured value to the processor 102 through wireless communication. In some embodiments, the measured values automatically communicated to the 30 processor 102 may also be communicated to a user of the arrangement 100 through the user device 108.
20195005 prh 04-01- 2019
Additionally, the processor 102 receives location information regarding at least two components 112, 114 that are utilized in the HVAC system. The location information is indicative of at least a relative location of the at least two components 112, 114 and their location with respect to the at least one 5 duct 104. The location information may be received through the user device 108.
Location information may also be received through manual input by a user of the arrangement 100 or through a separate file such a DWG file.
Further, in some embodiments, location information regarding a component io 112 may be received through the information gathering device 106. The information gathering device 106 may detect a component 112 and determine its location in the duct 104 e.g. through sensors. The location information may advantageously be obtained simultaneously to obtaining information regarding the layout and/or dimensions of the duct 104.
is The location information may also in some embodiments be received through e.g. wireless communication between a component 112 and the processor 102. In this case, a component 112 may comprise means for position sensing.
In some embodiments, it may be possible that the intended use of e.g. a 20 room comprised in the facility in which the HVAC system is comprised in is indicated, and the arrangement 100 has received or has access to target values for flow parameters such as air flow rates that should be pursued for different use scenarios. In this case a component 112, 114 such as a valve may be located at a location where a duct meets a room, and it may be 25 indicated that the room is intended e.g. for office use. The available target value information may suggest that a certain air flow rate should enter an office room, and the air flow rate through the vent is then a target value for a flow parameter at the valve location.
In embodiments of an arrangement 100 where the arrangement 100 30 receives target values for flow parameters based on use purposes, it may also be possible for the arrangement 100 to correct target values obtained through e.g. HVAC plans if the plans are not accurate regarding the use of e.g. rooms. For instance if a room that is in the HVAC plans (possibly received through e.g. a DWG file) used as office space is currently used as
20195005 prh 04-01- 2019 meeting room space for which a target value for a flow parameter such as an air flow rate is different, the correct target value may be used by the arrangement 100 in determining adjustment parameters.
Through embodiments of the present invention, an arrangement 100 may also create, through e.g. the information gathered by an information gathering device 106 and/or data received via other methods such as through user inputs, an HVAC plan e.g. in the form of a DWG file. Erroneous DWG files may thus be replaced with updated, corrected ones.
Utilizing the received first measured value for a second flow parameter and io the received location information, the processor 102 is configured to resolve a first determined value for a second flow parameter in the first duct location corresponding to the location of the first component 112. E.g., using a first measured value for a pressure at a first measuring location, a first determined value for a pressure at the first duct location, i.e., first is component 112 location may be resolved.
If the first measuring location is the first duct location, i.e., the location of the first component 112, the first determined value for e.g. pressure is equivalent to the first measured value for pressure. If the first measuring location is not equivalent to the first duct location corresponding to the first 20 component 112, the first determined value for the second flow factor such as pressure may be resolved otherwise, such as through calculations involving data related to the second flow parameter.
In an embodiment, the processor is configured to obtain flow parameter data which is related to the second flow parameter, wherein the flow 25 parameter data comprises information on theoretical changes of the second flow parameter as a fluid traverses through a duct comprising certain dimensions and/or layout. The flow parameter data may be obtained through a user device 108 or the processor 102 may have access to said data for example through wired or wireless communication such as an 30 internet connection. The flow parameter data may reside in a database 118.
For example, the aforementioned data may indicate that pressure drops by 1 Pa/m when traveling through a straight duct with certain dimensions. If a measured value for a flow parameter indicates a certain pressure at a certain measuring location, the processor 102 may then resolve a determined value for the pressure at for instance the first duct location corresponding to the first component 112.
Using the first received target value for the first flow parameter in the first duct location corresponding to the first component 112 and the first 5 determined value for the second flow parameter in the first duct location corresponding to the first component 112, the processor 102 may determine a first flow factor for the first component 112.
A flow factor K may in some embodiments be defined as
20195005 prh 04-01- 2019 io where Q is a fluid volume flow rate (e.g. in l/s) through the component 112, 114 and ΔΡ is a pressure drop across the component 112, 114, i.e. a pressure value that may be measured at the component location.
The processor 102 may in an embodiment also be configured to obtain adjustment data regarding a component 112, 114. The adjustment data may is be obtained through a user device 108 or the processor 102 may have access to said data for example through wired or wireless communication such as an internet connection. The adjustment data may reside in a database 118.
The adjustment data may for example comprise data that relates a certain 20 adjustment setting or adjustment parameter of a component 112, 114 to a flow factor. That is, for a certain type of component 112, 114, the adjustment data may specify that a certain value for K corresponds to a certain adjustment setting, such as level of openness.
Adjustment data may be available for a plurality of component types and an 25 HVAC system may comprise many different types of components 112, 114.
In an embodiment, an information gathering device 106 may also comprise means for obtaining identification data regarding a component 112, 114.
The identification data may be utilized to select appropriate adjustment data to be used. The identification data may be obtained via one or more 30 sensors, such as a camera, comprised in the information gathering device
20195005 prh 04-01- 2019
106. Methods such as pattern recognition, RFID technology, short-range communication, or barcode technology may be utilized.
A component 112, 114 may comprise a transmitter that transmits the identification data, which the information gathering device 106 may be 5 configured to receive, or the component 112, 114 and the information gathering device 106 may both comprise means for short range communication methods such as Bluetooth.
Using the determined first flow factor for the first component 112, the processor 102 may determine a first adjustment parameter for the first io component 112. The adjustment parameter may indicate e.g. the openness of for instance a valve or a damper e.g. in percent. A number may also be used, and different types of indications, for example aforementioned numbers or percentages may be used for different types of components 112, 114.
is The processor 102 also receives a second target value for at least one first flow parameter in a second duct location corresponding to the location of a second component 114 comprised in the HVAC system. Similarly to the aforementioned case regarding the first component 112, a second determined value for the second flow parameter in the second duct location 20 corresponding to the location of the second component 114 is resolved utilizing the received first measured value for the second flow parameter and the received location information. A second flow factor may then be determined accordingly utilizing the received second target value for the first flow parameter in the second duct location and the second determined value for the second flow parameter in the second duct location. Through the second flow factor, a second adjustment parameter may then be determined for the second component 114.
Accordingly, adjustment parameters may be determined for any number of components 112, 114 comprised in an HVAC system.
The determined adjustment parameters may then be communicated to a user of the arrangement 100 through providing an output, possibly through a user device 108. An arrangement 100 may in some embodiments comprise a plurality of user devices 108 and a plurality of users. The determined
20195005 prh 04-01- 2019 adjustment parameters may be e.g. displayed to a user through the user device 108 comprising a user interface 110.
An arrangement 100 may also be configured to automatically perform adjustments of the components 112, 114 according to the determined 5 adjustment parameters in one other exemplary embodiment, where the adjustment parameters are determined as explained above. In this case, the components 112, 114 may be digitally controlled and may, for instance, be adjusted by the processor 102 through wireless communication.
A processor 102 may additionally be configured to receive at least a io second measured value for at least a second flow parameter in a second measuring location in a duct 104. The at least second measured value may be used to update the determined adjustment parameters.
In one embodiment, a second measured value for the second flow parameter in a second measuring location, which is the first or second duct is location corresponding to the location of the first or second component 112,
114 is received. It may then be resolved that an updated determined second flow factor at the corresponding first or second location is equivalent to the second measured value. In a manner similar to that disclosed above, an updated flow factor may be determined for said first or second component 20 112, 114 utilizing the received first or second target value for the first flow parameter in the first or second duct location corresponding to the first or second component 112, 114 and the received second measured value for the second flow parameter in the first or second duct location. Through this, an updated first or second adjustment parameter for the first or second 25 component 112, 114 may be determined. Using a procedure similar to that before, an updated first or second adjustment parameter may then be determined for the at least one other component 112, 114, whichever is the component that does not reside at the second measuring location.
It can be easily understood that adjustment parameters may be determined 30 for any number of components 112, 114. Utilizing the received and possibly obtained information, one first measured flow parameter in a first measuring location may be used to determine adjustment parameters for any number of components 112, 114 comprised in an HVAC system that should result in received target values for second flow parameters. More measured flow 35 parameters in other measuring locations may be utilized to determine that
20195005 prh 04-01- 2019 either determined values for second flow parameters are not achieved in reality or that target values for first flow parameters are not achieved, and an arrangement 100 may update the determined adjustment parameters accordingly.
Using measured values, the arrangement 100 may take into account an error situation such as a leak in the duct 104. In a leak situation, the determined adjustment parameters may not actually lead to the received target values for first flow parameters and/or the determined values for second flow parameters. The measured values may be of the second flow io parameter and/or measured values may be received for the first flow parameter. Utilizing the measured values, updated adjustment parameters that may take a leak into account may be determined.
Advantageously, an arrangement 100 may comprise a plurality of sensors 116 through which measured values of one or more flow parameters may be is received. Thus, as adjustments of components 112, 114 are performed, the actual effect on one or more flow parameters may be observed, and further adjustments may be made in order to achieve the received target values for a flow parameter.
The receiving of measured values of flow parameters through sensors 116 20 and/or determining of updated adjustment parameters and/or automatic performing of adjustments may be initiated by a user of the arrangement 100 or any of said actions may be carried out at predetermined time intervals or continuously.
In further embodiments, an arrangement 100 may also comprise other 25 sensors, such as a mold sensor, a tvoc sensor (Total Volatile Organic
Compounds), a voc sensor (Volatile Organic Compounds), a temperature sensor, a sound level sensor, a humidity sensor, or a dust sensor. These sensors, along with one or more sensors 116 for measuring flow factors, may be utilized to determine the occurrence of a disorder situation, which a 30 user of the arrangement 100 may also be notified of through a user device 108. For example, a notification procedure may be initiated if a measurement made by a certain sensor exceeds a predetermined value or is outside of a predetermined range. The predetermined values or ranges may be e.g. set by a manufacturer of an arrangement 100, they may be
20195005 prh 04-01- 2019 obtained from a database, or they may be set through a user device 108 by a user of the arrangement 100.
A disorder situation may for instance be a leak, an odor nuisance, a sound nuisance, a temperature disorder, a smoke disorder, a humidity disorder, or 5 a mold situation.
For instance, detection of a leak may be done through observing that a measured value for e.g. a pressure at a measuring location does not match a determined value for a pressure at that location, where the determined value has been resolved using a measured value for pressure at another io measuring location.
An arrangement 100 may also be configured to store information regarding occurring disorder situations, solution procedures that have been performed as a response to the disorder situations, and the outcomes of the solution procedures. This way, an arrangement 100 may learn, based on the is previous information, to suggest to a user of the arrangement 100 a solution procedure in a certain disorder situation that may have a favorable outcome in order to overcome the disorder situation.
Figure 2 shows an exemplary information gathering device 106 according to an embodiment of the invention. In advantageous embodiments, the 20 information gathering device 106 is configured to maneuver inside a duct
104 or it may be configured to be coupled to an external device that may move inside the duct 104 in order to obtain the information regarding the duct 104 and/or possibly the location information or identification data regarding a component 112.
The information on the size, shape, and directional changes in a duct 104 may be obtained through one or more sensors or other devices comprised in the information gathering device 106. In the embodiment of Fig. 2, a flex sensor 202 and a laser scanner 204 are utilized. E.g. other sensors that may be utilized include a gyroscope, accelerometer and/or a camera.
In Fig. 2, a flex sensor 202 is comprised in a flexible conduit 206 that may be used by a TAB technician or duct cleaner or other user of the information gathering device 106 to guide the device 106 inside a duct 104 e.g. by pushing. The flex sensor 202 may detect if a bend occurs in the duct 104 as
20195005 prh 04-01- 2019 the information gathering device 106 traverses through the duct. The direction and magnitude of e.g. a bend may be detected.
The information gathering device 106 may also comprise a laser scanner 204. The laser scanner 204 may analyze the duct 104 in order to collect 5 data on the dimensions such as shape and/or diameter of the duct 104.
Information regarding the length of a duct 104 or certain portions thereof may for example be obtained through a flexible conduit 206 or the information gathering device 106 may comprise some other means for position determination through which distance/length information may be io obtained.
The information gathering device 106 may advantageously in some embodiments also comprise means for cleaning of a duct 104. The device 106 may be used for cleaning or additionally (preferably simultaneously with the cleaning) or instead of the cleaning for obtaining information on the duct is configuration. For instance, the device 106 may comprise a brush 208 that may e.g. remove dust from the walls of a duct 104 as the information gathering device 106 traverses therein.
Having regard to embodiments where the information gathering device 106 may obtain information regarding components 112, in addition to obtaining 20 identification information through e.g. the methods mentioned above, the information gathering device 106 may obtain location information regarding a component 112, 114. This may be done by utilizing sensors comprised in the information gathering device 106 and position data that may also be acquired through sensors or e.g. by measuring at least one distance that the 25 information gathering device 106 has traversed for instance through the flexible conduit 206.
In preferred embodiments, the information gathering device 106 may transmit the gathered information to the processor 102 through wireless communication.
In other embodiments, the information gathering device 106 may comprise other methods of maneuvering through a duct and be a robot or a drone and/or comprise other ways for gathering information, such as through infrared sensing.
20195005 prh 04-01- 2019
The information gathering device 106 may be of any shape and may comprise a body portion 210 onto which sensors, cleaning means such as a brush 208, and/or maneuvering means such a flexible conduit 206 may be attached. Alternatively, sensors and means for maneuvering may be 5 comprised inside a body portion 210. A body portion 210 may be comprised of a material such as metal or plastic.
In other embodiments, an information gathering device 106 may be configured to be coupled with an external device. In such embodiments, the external device may be configured to maneuver inside a duct 104 and may io additionally comprise means for cleaning a duct, such as a brush, while the information gathering device 106 may comprise e.g. sensors for gathering information (as described elsewhere in this document) and coupling means such as one or more clips which may be utilized to couple the information gathering device 106 to the external device.
is An arrangement 100 may be configured to communicate to a user of the arrangement 100 a current location of an information gathering device 106 and/or the path of travel of said device 106 in a duct configuration within some time interval. Also information, such as camera footage, obtained by the device 106 may optionally be communicated to a user. The 20 communication may be performed through a user interface 110 of a user device 108.
Embodiments of the arrangement 100 may comprise a plurality of different user devices 108 with different user interfaces 110. For instance, one user device 108 may be a mobile handheld device intended to be used by a TAB 25 technician, where the first user interface 110 is configured to show at least the determined adjustment parameters. The user interface 110 may, for instance, show a layout of a duct configuration along with the respective locations of components 112, 114, and may visually indicate a determined adjustment setting for one or more of the components 112, 114. The TAB 30 technician may then perform the adjustments as indicated.
In embodiments where the arrangement 100 comprises sensors 116 from which measured flow parameters are obtained, a user device 108 may also indicate these measured values. If a measured value suggests that a target value for a flow parameter is not achieved, updated adjustment settings may 35 be shown to e.g. a TAB technician. Also other information that is received,
20195005 prh 04-01- 2019 obtained, or determined by the arrangement 100 may be displayed or otherwise communicated to the user.
An arrangement 100 may additionally or alternatively comprise a user device 108 intended to be used by a property owner, property maintenance 5 service, or client of a TAB-performing enterprise. This user device 108 may be a mobile device or some other computing device such a desktop computer comprising a user interface 110 which may display similar or other information than that which is relevant for a TAB technician, such as progress of duct cleaning work. A property owner may wish to monitor the io HVAC system through the user interface 110, and also notifications of error situations and suggested solution procedures may be communicated through the user interface 110.
An arrangement 100 may also comprise a web interface through which information may be communicated to a user.
is A component 112, 114 for which adjustments may be determined by an arrangement 100 may in an embodiment include a protractible damper. An exemplary protractible damper 300 is seen in Figure 3. Advantageously, the damper 300 is adapted to be incorporated with a duct system through first drilling a hole into a duct 104 and inserting the damper 300 into the hole.
Upon insertion, the protractible damper 300 is preferably in a first state, seen in 300A, where the protractible damper 300 is substantially rod-shaped and may approximately predominantly take the shape of a rod body 302. The rod body 302 may preferably be comprised of a rigid material, such as metal or plastic.
Once inserted, the protractible damper 300 may be configured to reside in the hole in the duct 104 so that a guiding element 304 may reside on the outside of the duct 104, or in other words, on the opposite side of the duct wall than the rod body 302.
A protractible damper 300 may in some embodiments also comprise a 30 sealing element 306 that may seal the hole in the duct wall, i.e. act as a seal between the opposite sides of the duct wall at the location of the hole.
A protractible damper 300 may optionally additionally comprise a fixing panel 308, which may be located adjacent to the sealing element 306 in order to more effectively secure the protractible damper 300 to the duct 104.
20195005 prh 04-01- 2019
The protractible damper 300 may through the fixing plate 308 or through other securing means be secured to the duct 104, such as through use of nails, screws, or staples.
After insertion into a hole in a duct 104, the guiding element 304 may be manipulated to bring forth transformation of the protractible damper 300 from a first state to a second state, the second state being depicted in 300B.
In the second state, the protractible damper 300 embodies a shape which comprises a surface area that is larger than that of the rod body 302. In Fig.
3, extension elements 312 are extended from the protractible damper and a io plurality of extension elements 312 form a shape with a surface area that is essentially circular. The formed shape may be of another shape, but preferably the shape is substantially similar to the inner dimensions of the duct 104 that the protractible damper 300 is configured to be inserted into.
In the embodiment of Fig. 3, the aforementioned transformation is brought is about by pushing on the guiding means 304. Said pushing will lead to extension of the extension elements 312 from the rod body 302 through extending means 310. The extending means 310 may be a wire or cable, possibly made of metal material, and the extension elements may be essentially flat elements that are configured to be extended by the attached 20 extending means 310. The extension means 310 may extend from the rod body 302 by way of a rod extender portion 314, which may be visible in the first state and contained inside the rod body 302 in the second state.
An extension element 312 may be connected to one or more adjacent extension elements 312 (or a rod body 302 in the case of the innermost 25 extension element 312) through one or more hinges or flexible joints 316, shown in 300C.
The extension elements 312 may be of any shape, but in the embodiment of Fig. 3, they are shaped so that when all of the extension elements 312 are in the fully extended state, i.e., when the protractible damper 300 is in a 30 second state, the surface area formed by the extension elements 312 is essentially circular.
Extension elements 312 may comprise metal or plastic or some other solid material.
20195005 prh 04-01- 2019
The protractible damper 300 may advantageously be readily transformed also from the second state to the first state. In an embodiment, this may be done by pulling on the guiding element 304. Pushing may lead to transformation from a first state to a second state, while pulling may lead to 5 transformation from a second state to a first state.
After insertion, adjustment of a protractible damper 300 in the second state may be carried out by further manipulation of the guiding means 304. Rotation of the guiding means 304 may lead to a rotation of the rod body 302 and the attached extension elements 312. Thus, the position of the io protractible damper 300 in the duct 104 may be adjusted and the amount of fluid being able to pass the protractible damper 300 per time unit may be controlled. That is, a desired adjustment setting of the protractible damper 300 is achieved through manipulation of the guiding means 304.
Removing of a protractible damper 300 from a duct 104 may be is conveniently carried out by first removing possible securing means and then pulling of the guiding means 304 in order to ensure that the damper 300 is in a first state. The protractible damper 300 may then be removed from a duct 104 and a hole where the damper 300 has resided may be filled in a case where the damper 300 is to be removed e.g. permanently.
Figure 4 shows steps that may be taken in a method according to the present invention. In some embodiments, an information gathering device 106 may be obtained at 402, and one or more ducts 104 comprised in an HVAC system may optionally be cleaned 404. Information regarding the dimensions and/or layout of the at least one duct 104 is received in 406.
In step 408, a first target value for at least one first flow parameter in a first location in the at least one duct 104 corresponding to the location of a first component 112 is received, while a first measured value for at least a second flow parameter in a first measuring location of the duct 104 is received in 410. Location information regarding at least two components 30 112, 114 comprised in the HVAC system is received 412, wherein the location information comprises at least information regarding a relative location of the at least two components 112, 114 and their location with respect to the at least one duct 104.
20195005 prh 04-01- 2019
At 414, a determined value for the second flow parameter in the first duct location corresponding to the location of the first component 112 is resolved utilizing the received first measured value for a second flow parameter and the received location information. Then, in 416, a first flow factor may be 5 determined for the first component 112 using the received first target value for the first flow parameter in the first duct location corresponding to the first component 112 and the first determined value for the second flow parameter in the first duct location. Through the determined first flow factor, a first adjustment parameter may be determined in 418 for the first io component 112.
A second target value for the first flow parameter in the second duct location corresponding to the location of a second component 114 is received at 420, and, as for the first component 112, in 422, a determined value for the second flow parameter is resolved at the second duct location, and a is second flow factor for may then be determined in 424, through which a second adjustment parameter may be determined in 426 for the second component 114.
In some embodiments a measured value may be received 410 any number of times and adjustment parameters may be accordingly determined any 20 number of times.
Steps taken in a method according to the present invention may also be conducted in an order differing from that which is presented in Fig. 4. As can be easily understood, e.g. receiving of target values 408 and 420 may for example both happen simultaneously and possibly e.g. after step 410 of 25 receiving a measured value.
The invention has been explained above with reference to the aforementioned embodiments, and several advantages of the invention have been demonstrated. It is clear that the invention is not only restricted to these embodiments, but comprises all possible embodiments within the 30 spirit and scope of inventive thought and the following patent claims.
The features recited in dependent claims are mutually freely combinable unless otherwise explicitly stated.

Claims (12)

1. A damper (300) for use in an arrangement for adjusting flow of a duct (104), wherein the damper is substantially rod-shaped in a first state, and in
5 a second state, extending means (310) are extended from the rod shape, and extension elements (312) attached thereto are also simultaneously extended from a rod body (302), the second state leading to the damper embodying a shape of predetermined form.
2. The damper of claim 1, wherein in the second state, the extension io elements form a shape with a surface area that is essentially circular.
3. The damper of any of the previous claims, wherein the damper is configured to be inserted into a hole in a duct, the damper additionally comprising a guiding element (304) that is configured to reside on the outside of the duct.
is
4. The damper of claim 3, wherein the transformation of the damper from the first state to the second state is brought about through manipulation of the guiding element.
5. The damper of claim 4, wherein pushing on the guiding element leads to the transformation from the first state to the second state and pulling on
20 the guiding element leads to transformation from the second state to the first state.
6. The damper of any of the previous claims, wherein the extending means are wire or cable and the extension elements are essentially flat elements that are configured to be extended by the attached extending
25 means.
7. The damper of any of the previous claims, wherein the damper is essentially protractible and additionally comprises a rod extender portion (314) that is used to enable extending of the extending means from the rod body, the rod extender portion being visible in the first state and contained
30 inside the rod body in the second state.
8. The damper of any of the previous claims, wherein an extension element is connected to one or more adjacent extension elements through one or more hinges or flexible joints (316).
9. The damper of any of the previous claims, wherein the damper is 5 configured to be secured to a duct and the damper is adjusted by further manipulation of the guiding element.
10. The damper of claim 9, wherein the further manipulation is rotation of the guiding element, which leads to rotation of the rod body and the attached extension elements, wherein the rotating and consequential io positioning of the damper with respect to a duct enables control of an amount of fluid being able to pass the damper per time unit.
11. The damper of any of the previous claims, wherein the damper is configured to be inserted into a hole in a duct wall and additionally comprises a sealing element (306), wherein the sealing element is is configured to seal the hole.
12. The damper of claim 11,wherein the damper additionally comprises a fixing panel (308) located adjacent to the sealing element to secure the damper to the duct.
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