Technical field

The application relates generally to an exhaust-air blower and exhaust-air sys- tem of a building. Background

The most popular mode of ventilation in buildings, e.g. apartment buildings, from the 1960s to the 21 ^st century, has been mechanical exhaust ventilation.

In the mechanical exhaust ventilation system of apartment buildings, it is by means of an exhaust-air blower installed in connection with an exhaust air duct that indoor air is extracted by way of apartment-specific exhaust air valves into the exhaust air duct, along which the air being removed from indoor spaces is then conducted to the roof of the apartment building.

The extraction of air from apartments by the blower generates therein a vacu- um, it being by virtue of such vacuum that the fresh air replacing the outgoing air arrives in the apartments either controllably by way of fresh air valves or uncontrollably through the apartment building’s structures.

The blowers operate usually at two speeds and with clock control. Hence, the timer-controlled blower runs at either half or full capacity, depending on an es- timated utilization rate of the apartment building. Summary

One objective of the invention is to overcome problems of the prior art and to provide a smart and compact exhaust-air blower, by means of which it is pos- sible, on the basis of measurement data supplied by sensors, to attain a needs-based ventilation, thereby preventing e.g. a loss of heat energy through ventilation, improving living comfort, increasing safety in apartments, eliminat- ing a feeling of draft from the apartment, enabling summertime nocturnal venti- lations in dwellings, enhancing fire safety and eliminating mechanical sounds of blowers.

One objective of the invention is attained with an exhaust-air blower and sys- tern according to the independent claims. According to one embodiment, the exhaust-air blower of a building comprises a blower motor, its control unit, and a shroud with the blower motor and the control unit fitted thereinside. Inside the shroud is further installed a sensor unit, the blower motor operation being controlled on the basis of a measure- ment conducted by at least one of its sensors on the exhaust air arriving at the exhaust-air blower.

According to one embodiment, the exhaust-air system comprises a plurality of the foregoing type exhaust-air blowers, a distribution board, and a power sup- ply cable (356) between the distribution board and each exhaust-air blower. Other embodiments are presented in the dependent claims.

Brief description of the figures

Exemplary embodiments of the invention will now be described more closely with reference to the accompanying figures: figs. 1 a-f show the construction of an exhaust-air blower in views from various directions and in cross-sections without a blower motor

fig. 1 g shows the blower in an exploded view without a motor

fig. 2 shows the functional units of the blower

fig. 3 shows an exhaust-air system in a principle view

Detailed description of the figures Figs. 1 a-g show an exhaust-air blower (roof fan) 100 installable in an exhaust air duct pipe penetration of a building 351 , e.g. an apartment building or a row house.

The blower 100 is mountable on the end of an exhaust air duct extended from the building’s 351 interior to its roof, the outgoing air thus leaving the building 351 by way of the blower 100.

The blower 100 has a shroud (diffuser) 102, whose function is to protect its in- ternal parts from the effects of weather and from mechanical impacts. The shroud 102 is made of thin plate whose material is aluminum and/or steel.

The shroud 102 comprises side members 104, at least one of which includes air openings 105 for discharging the exhaust air from the shroud 102 readily and soundlessly into a space (outdoor air) surrounding the blower 100. It is by increasing the surface area of the air openings 105 that a capability is provided of reducing the outflow rate of exhaust air from the shroud 102, whereby the airflow-induced noise nuisance is eliminated or at least remarkably reduced.

The side members 104 are connected to each other with corner pieces 106, which are made up of an outer portion 107 and a triangular portion 108 at- tached to each other, the latter being shorter than the former in height.

The shroud 102 further comprises a bottom plate 110 which is fixed to a bot- tom edge or part 109 of the side members 104 and includes a penetration hole

111 for a pipe penetration, and a cover 112 which is spaced from a top edge 114 of the side members 104 in such a way that the exhaust air is able to dis- charge from the shroud 102 by way of a gap 116 between the top edge 114 and the cover 112 of the side members 104.

Each corner piece 106 has a fixed bar member 118, whose function is to raise the cover 112 off the top edge 114 of the side members 104. Alternatively, the bar member 118 can be constructed as a spring structure, which, once a blower motor 220 of the blower 100 is started, opens the gap 116 in response to air pressure by lifting the cover 112 away from the side members 104 and respectively closes the gap 116 as the motor 120 shuts down and the air pres- sure decreases.

The cover 112 is shaped to be spaced at a substantially equal distance from each side member. Since the opposite side members 104, provided with the air openings 105, have the top edge 114 which is substantially straight and the top edge 114 of the other two opposite side members 104 is curved, the cover

112 shall have a curved design, whereby the water accumulating on top of the cover 112, and the melting snow which turns into water, shall flow away along the surface of the cover 112. Alternatively, when all side members 104 are straight in terms of their top edges 114, the cover can be constructed as a flat structure provided that the snow and water left on the cover 112 do not inflict harm to the structures of the blower 100.

Inside the shroud 102 is installed an air deflector 115 in line with the air open- ings 105 present in each side member 104, such that the air deflectors 115 are spaced from the side member 104, and it is therethrough that the exhaust air is capable of escaping by way of the air openings 105 from the shroud 102 as si- lently as possible. It is also by means of the air deflectors 115 that the assault of wind, rain and snow into the interior of the protective shroud 102 is prevent- ed.

Fig. 2 shows functional components 124, 220, 222, 228, 230, 234 of the blow- er 100 installed inside the shroud 102.

Inside the shroud 102 is installed a motor 220 whose function is to draw the air to be removed from an apartment into an exhaust air duct and therealong to the blower 100 by way of a pipe penetration fitted in the penetration hole 111 , wherein the motor 220 then blows the outgoing air through the blower’s 100 structure as well as through the air openings 115 and the gap 116 away from the building 351. The motor 220 is installed in the middle of a space defined by the structural elements of the shroud 102.

The shroud 102 has further installed thereinside a protective enclosure 125, in which is positioned a central processing unit 126 that manages operation of the blower 100, its functional components 228, 230, 234, a sensor unit (mod- ule) 124 and a control unit (module) 222 used for assisting control of the blow- er 100. The protective enclosure 125 is mounted against one side member 104, which has neither air openings 105 nor an air deflector 115 attached thereto.

The protective enclosure 125 present inside the shroud 102 has installed therein a control unit 222, which is intended for controlling the motor 220 and whose control automation has a function of regulating the power of the motor according to instruction received thereby. The control unit 222 can be optional- ly positioned in a spaced relationship with the protective enclosure 125 outside the same.

Inside the protective enclosure 125 is further installed a sensor unit 224, it be- ing on the basis of a measurement, conducted by at least one of its sensors on the exhaust air arriving at the blower 100, that automation of the control unit 222 is instructed to regulate operation of the motor 220. The sensor unit 124 can be optionally positioned in a spaced relationship with the protective enclo- sure 125 outside the same.

The sensor unit 224 includes at least one of the following: a temperature, hu- midity, carbon dioxide, VOC gas and volume air sensor. Inside the protective enclosure 125 is further installed the above-mentioned central processing unit 126 with a function of analyzing, on the basis of a measurement by at least one sensor, the demand for controlling the motor 220 and, if necessary, instructing the control unit 122 to regulate operation of the motor 220.

The central processing unit 126 includes a processor element 228 used for carrying out instructions defined by a user or some application program and for processing data.

The central processing unit further includes a data transfer element 230, by means of which the central processing unit 126 receives information by way of a wireless communication link from outside the blower 100 and transmits in- formation by way of a wireless communication link to the outside of the blower 100. The data transfer element 230 can be optionally positioned in a spaced relationship with the protective enclosure 125 outside the same.

The data transfer element 230 comprises e.g. a wireless 3G/4G network com- ponent, by means of which the central processing unit communicates with a device external of the blower 100.

The central processing unit 126 may include a physical user interface element 232, by means of which the user is able to input commands and data and/or to receive data from the central processing unit 126.

The user interface element 232 is e.g. a communication interface capable of having connected thereto by means of a connection cable e.g. an external computer, a display- and keyboard-equipped user interface or a touch screen- equipped smart device.

The central processing unit 126 further includes a memory element 234 for the storage and maintenance of applications and data. The memory element 234 may comprise at least one memory, e.g. one, two or three memories.

The memory element 234 may include a data transfer application 240 control- ling operation of the data transfer element 230, a user interface application 242 controlling operation of the user interface element 232, an analysis application 244 intended for the processing of data arriving from the sensor unit 124, and a control application 246 intended for managing the control unit 222 which regulates operation of the motor 220.

The sensor unit 124 includes e.g. temperature, humidity, carbon dioxide, VOC gas and volume air sensors.

Data transfer between the sensor unit 124 and the central processing unit 126, between the central processing unit 126 and the control unit 222, as well as between the control unit 222 and the motor 220 is carried out by means of a fixed cable connection.

The memory element 234 has stored therein predetermined limit values for each variable to be measured and, when the measurement data coming from the sensor indicates that the limit value has been exceeded, the analysis ap- plication 244 determines whether operation of the motor 220 has to be regu- lated thereby. The limit values determine whether the power (rotation speed) of the motor 220 is maintained the same, whether it is reduced or increased.

It is e.g. for temperature that limit values can be set in such a way that as the temperature of exhaust air falls below 20°C, the central processing unit 126 in- structs the control unit 222 to reduce power of the motor 220 for reducing draft in the building’s 351 apartments. On the other hand, if the temperature of ex- haust air exceeds 23°C, the central processing unit 126 instructs the control unit 222 to increase power of the motor 220 for enhancing ventilation, and if the temperature of exhaust air is within the range of 20-23°C, the current pow- er of the motor 220 is maintained. The same applies also to other measurable variables. In addition, the central processing unit 126 is capable of concluding a ventilation enhancing or reducing demand on the basis of measurement data relating to two or more measurement variables based on predetermined limit values.

In addition, the analysis application 244 is capable of determining a demand for ventilation on the basis of measurement data relating to two or more meas- urable variables. The analysis application 244 is e.g. capable of detecting from the exhaust air a fire in the building 351 by analyzing measurement data com- ing from VOC, carbon dioxide, temperature, and humidity sensors and, based on the analysis, the central processing unit 126 instructs the control unit 222 to enhance performance of the motor 220 for the removal of smoke. In addition, after detecting a fire, the central processing unit 126 may communicate in a wireless manner by way of the data transfer element 230 this information to some other external terminal, i.e. produce a fire alarm.

Operation of the blower 100 can be monitored and/or controlled in real time by means of a terminal device, e.g. a desktop or portable computer or a smart phone, using browser-based control software intended for managing the blow- er 100. By means of the terminal device’s control software, it is possible to monitor operation of the blower 100 or several blowers by studying measure- ment data coming from various sensors and analysis data generated on the basis thereof, to receive notifications, e.g. a fire alarm, and to control manually the operation of the blower(s) 100.

Fig. 3 shows an exhaust-air system 352 intended for the building 351 and in- cluding several blowers 100 according to the foregoing figures.

The system 352 further includes a distribution board 354, which is in communi- cation with each blower 100 by way of power supply cables 356. It is within the system 352 that the blowers 100 communicate with each other by means of data transfer elements in a wireless manner, and one of the blowers 100 (marked with an asterisk) functions as a principal blower by way of which all other blowers 100 transmit information to an external terminal de- vice and by way of which they also receive information used for controlling the same.

The foregoing only presents a few embodiments by way of example. The prin- ciple of the invention can naturally be varied within the scope of protection de- fined by the claims, regarding e.g. implementation details as well as fields of use.