WO2018202312A1

WO2018202312A1 - Electric extractor fan

Info

Publication number: WO2018202312A1
Application number: PCT/EP2017/060767
Authority: WO
Inventors: Per-Ola HÅRD
Original assignee: Fresh Ab
Priority date: 2017-05-05
Filing date: 2017-05-05
Publication date: 2018-11-08

Abstract

The invention concerns an electric extractor fan(1) comprising a housing (2), in which an electric motor is installed to expel air from a room (4) by means of a fan wheel (5). The electric extractor fan (1) comprises a humidity sensor installed in said housing (2) and adapted to start the electric motor when a humidity level, detected by means of the humidity sensor, exceeds a set level. The electric extractor fan (1) does also comprise a gas sensor installed in said housing (2) and adapted to start the electric motor when level of a gaseous air contaminant, especially methane, detected by means of the gas sensor, exceeds a set level.

Description

ELECTRIC EXTRACTOR FAN

Technical Field

The present invention concerns an electric extractor fan comprising a housing, in which an electric motor is installed to expel air from a room by means of a fan wheel, wherein the electric extractor fan comprises a humidity sensor installed in said housing and adapted to start the electric motor when a humidity level, detected by means of the humidity sensor, exceeds a set level. Prior Art

Document EP 1 008 762 B1 reveals an electric extractor fan that can be automatically controlled by means of different detected conditions, such as humidity, temperature, or presence of a person. This is advantageous compared to traditional extractor fans, which often are operated solely by means of a manual switch, often in combination with a light switch and often in combination with a timer that ensures a certain over-run, since the electric extractor fan is started only when required, e.g. due to increased humidity, and by this serves energy.

Object of the Invention

A drawback of the known electric extractor fan is that it, if started only due to an increased humidity level, causes discomfort when used for instance in a bathroom, where odor is an issue too. Brief Summary of the Invention

According to the invention, in an electric extractor fan according to the preamble, this is achieved in that that the electric extractor fan comprises a gas sensor installed in said housing and adapted to start the electric motor when level of a gaseous air contaminant, especially methane, detected by means of the gas sensor, exceeds a set level. By this the electric extractor fan can be started automatically not only when a set humidity level is exceeded but also when a set level of a gaseous air contaminant, such as methane, which is indicative of odor, is exceeded. That makes it possible to avoid start of the electric extractor fan for instance just because light is turned on in the room or due to presence of a person, which saves not only electric energy but also heat energy, at least when temperature outside the room differs from the one inside the room. And yet, for a person in the room comfort is maintained at the highest possible level, as both humidity and said gaseous air contaminant are dealt with when necessary.

Preferably, the housing of the electric extractor fan comprises a control chamber that encloses the gas sensor and comprises a vent hole that opens towards said room to render entry of air from the room to the gas sensor possible. The control chamber with the vent hole ensures safe conditions for the gas sensor and preferably too for the humidity sensor and renders install easy.

Preferably, said vent hole is arranged in a part of the housing apart from an air duct in which the fan wheel is mounted, wherein said vent hole preferably has an entry arranged in a side wall of said housing. By this one ensures that air in the room is monitored and not by chance air entering into the room via a ventilation duct through which air is to be expelled from the room.

Preferably, a command panel for entry and/or indexing of fan control data is arranged on a front wall of the housing in front of said control chamber. By this it is rendered easy for a user both to change and read fan settings, and for a producer to gather necessary control means in one spot, i.e. in said control chamber.

Possibly, a front cover is detachably arranged in front of said front wall by means of legs that protrude backwards from the front cover towards said front wall. The front cover changes appearance of the electric extractor fan. It can be used to hide the command panel and to hide the fan wheel entirely or, if provided with an opening, at least to hide parts of the fan wheel. Yet, in any way, said legs ensure that enough air can pass to said air duct.

Preferably, said front cover with its legs and said front wall are aligned with each other and held together by means of magnetic means on foot parts of said legs and corresponding magnetic means hidden behind said front wall. The magnetic means render it possible to shape the front wall all smooth, which improves appearance of the electric extractor fan when no front cover is used. And, further, if a front cover is used, maintenance and changing of fan settings is still easy to accomplish thanks to easy removal and reinstall of the front cover.

Preferably, said housing is divided into a rear housing part that is to be permanently mounted on a wall or ceiling of said room and a front housing part that is detachably mounted on the rear housing part, wherein the rear housing part comprises a sealed chamber for electric mains and the front housing part comprises said control chamber. This division renders install easy, as the front housing part can be used to hide mounting screws and the like used to mount the rear housing part onto a wall or ceiling. And, further, it improves safety, as a user cannot come into contact with mains when removing the front housing part for cleaning purposes.

Preferably, the sealed chamber and the control chamber are detachably connected to each other by means of a low voltage plug connector, of which a rear part is fixedly arranged on the rear housing part and a front part is fixedly arranged on the front housing part. By this cleaning of the electric extractor fan is rendered very easy, as the crucial parts thereof from a clean- ing point of view thus can be easily accessed.

Brief Description of the Drawings

In the drawings preferred embodiments of the electric extractor fan according to the invention are shown, wherein:

Fig. 1 is an isometric front view of a first embodiment;

Fig 2 is an isometric rear view of the first embodiment;

Fig 3 is an isometric front view of the second embodiment;

Fig 4 is an isometric rear view of the second embodiment;

Fig 5 is an isometric rear view of a housing front portion of both the first and second embodiment;

Fig. 6 is an isometric front view of a housing rear portion of both the first and second embodiment; and Fig. 7 is an isometric rear view of a front cover of the second embodiment.

Detailed Description of Preferred Embodiments

The electric extractor fan 1 according to both embodiments comprises a housing 2 that has a generally parallel epipedic shape with rounded corners and a slightly bulging front. The two embodiments differ only in that the second embodiment comprises an extra front cover 14, which alters the overall appearance of the electric extractor fan 1 and brings about some technical effects, too, described below.

The housing 2 as such is divided into a rear housing part 18 (c.f. fig. 6) and a front housing part 19 (c.f. fig 5). The rear housing part is to be permanently mounted on a wall or ceiling of a room, which is roughly indicated by 4 in figs. 1 and 3 and comprises some sort of ventilation duct (not shown), to which the electric extractor fan is 1 tightly connected by means of a rear tubular fitting 22. Further, the rear housing part 18 comprises a sealed chamber 20, which is used to safely connect the electric extractor fan 1 to electric mains.

The front housing part 19 is detachably mounted on the rear housing part 17, preferably by means of a snap fit arrangement. It comprises a control chamber 8 that houses low voltage electronic means for fan control. The sealed chamber 20 and the control chamber 8 are detachably connected to each other by means of a low voltage plug connector 21 , of which a rear part 21 ' (c.f. fig. 6) is fixedly arranged on the rear housing part 18 and a front part 21 " (c.f. fig. 5) is fixedly arranged on the front housing part 19. Thanks to these measures the rear and front housing parts 18, 19 can be easily and safely separated, for instance for cleaning purposes, and then be easily put together again.

In order to ensure high comfort and to reduce energy consumption to a minimum, according to the invention the electric extractor fan 1 comprises a gas sensor 7, which is installed inside of the control chamber 8 and is indicated only schematically in fig. 5 by means of a first dashed ring 7. The gas sensor 7 can for instance be a TGS 2600™, which is made by Figaro US, Inc., and can detect gaseous air contaminants, such as ethanol and especially methane.

Out of the same reason, that is high comfort and low energy consumption, the electric extractor fan 1 according to the invention can also comprise a humidity sensor 6 of a sort well known in the art. The humidity sensor 6 too is installed inside of the control chamber 8 and is indicated only schematically in fig. 5 by means of a second dashed ring 6.

For ambient air from the room 4 to safely reach the humidity sensor 6 and the gas sensor 7, the control chamber 8 comprises a vent hole 9 that has an entry 9' arranged in a side wall 1 1 of the rear housing part 18. To be more precise, the entry 9' is placed as far away as possible from an air duct 10 in which a fan wheel 5 of the electric extractor fan 1 and an electric motor 3 driving the fan wheel are mounted.

Besides the two sensors 6, 7 the low voltage electronic means for fan control mentioned before do also comprise a command panel 12 for entry and/or indexing of fan control data. The command panel 12 as such is arranged on a front wall 13 of the front housing part 19 in front of the control chamber 8 and communicates with the remaining electronic means inside the control chamber 8.

Thanks to the ability of the gas sensor 7 to detect methane, and hence odor, and the ability of the humidity sensor 6 to detect humidity, the electric extractor fan 1 according to the invention can be programmed to run automatically only when necessary from both a health and a comfort point of view, that is when certain levels of humidity or methane are exceeded for instance in a bathroom. By this energy consumption of the electric extractor fan 1 according to the invention can be reduced compared to electric extractor fans controlled manually or only by means of one sensed parameter, such as humidity.

As indicated before, the first and second embodiment of the present invention differ only in that the electric extractor fan 1 according to the second embodiment comprises a front cover 14. The front cover 14 is detachably arranged in front of the front wall 13 of the front housing part 19 by means of legs 15 that protrude backwards from the front cover 14 towards said front wall 13. The front cover 14 with its legs 15 and the front wall 13 are aligned with each other and held together by means of magnetic means 16 on foot parts of said legs 15 and corresponding magnetic means 17 hidden behind the front wall 13. The magnetic means 16, 17 can for instance comprise pairs of magnets or pairs of one magnet and one magnetic disc, each.

As shown, the front cover can comprise a central orifice 23. The orifice 23 is much smaller than the air duct 10 of housing 2 and does therefore prevent a user to inadvertently come into contact with quickly moving parts of the fan wheel. Yet the overall air volume expelled by the electric extractor fan 1 according to the second embodiment is not reduced compared to the first embodiment, because the protruding legs 15 create an alternative air passage. Further, thanks to the alternative air passage created by said legs 15, it would even be possible to eliminate the orifice 23 entirely and by that to provide yet another fan design,

Claims

1 . An electric extractor fan (1 ) comprising a housing (2), in which an electric motor (3) is installed to expel air from a room (4) by means of a fan wheel (5), wherein the electric extractor fan (1 ) comprises a humidity sensor (6) installed in said housing (2) and adapted to start the electric motor (3) when a humidity level, detected by means of the humidity sensor (6), exceeds a set level, c h a r a c t e r i z e d in

that the electric extractor fan (1 ) comprises a gas sensor (7) installed in said housing (2) and adapted to start the electric motor (3) when level of a gaseous air contaminant, especially methane, detected by means of the gas sensor (7), exceeds a set level.

2. The electric extractor fan (1 ) according to claim 1 , wherein said housing (2) comprises a control chamber (8) that encloses the gas sensor (6) and comprises a vent hole (9) that opens towards said room (4) to render entry of air from the room (4) to the gas sensor (7) possible.

3. The electric extractor fan (1 ) according to claim 2, wherein said control chamber (8) encloses the humidity sensor (6) too.

4. The electric extractor fan (1 ) according to claim 2 or 3, wherein said vent hole (9) is arranged in a part of the housing (2) apart from an air duct (10) in which the fan wheel (5) is mounted.

5. The electric extractor fan (1 ) according to claim 4, wherein said vent hole (9) has an entry (9') arranged in a side wall (1 1 ) of said housing (2).

6. The electric extractor fan (1 ) according to claim 5, wherein a command panel (12) for entry and/or indexing of fan control data is arranged on a front wall (13) of the housing (2) in front of said control chamber (8).

7. The electric extractor fan (1 ) according to claim 5 or 6, wherein a front cover (14) is detachably arranged in front of said front wall (13) by means of legs (15) that protrude backwards from the front cover (14) towards said front wall

(13) .

8. The electric extractor fan (1 ) according to claim 7, wherein said front cover

(14) with its legs (15) and said front wall (13) are aligned with each other and held together by means of magnetic means (16) on foot parts of said legs (15) and corresponding magnetic means (17) hidden behind said front wall (13).

9. The electric extractor fan (1 ) according to any of claims 2-8, wherein said housing (2) is divided into a rear housing part (18) that is to be permanently mounted on a wall or ceiling of said room (4) and a front housing part (19) that is detachably mounted on the rear housing part (18), wherein the rear housing part (18) comprises a sealed chamber (20) for electric mains and the front housing part (19) comprises said control chamber (8).

10. The electric extractor fan (1 ) according to claim 9, wherein the sealed chamber (20) and the control chamber (8) are detachably connected to each other by means of a low voltage plug connector (21 ), of which a rear part (21 ') is fixedly arranged on the rear housing part (18) and a front part (21 ") is fixedly arranged on the front housing part (19).