Method and device for ventilation of a space

Field of the invention

The present invention relates to a method for ventilation of a space according to the preamble of claim 1.

The invention relates also to a ventilation device for ventilation of a room according to the preamble of claim 10.

Background of the invention Swedish patent specification SE 521038 C2 refers to a device for ventilation of a space, which device is configured for being fitted in a ceiling. A problem with the invention according to SE 521038 C2 is that it can only cool air. It therefore involves no element or method which would prevent cold draught in a space. Cold draught means that when room air is cooled by a cooling wall element, e.g. a window, the cooled room air may move downwards towards the floor in the space at a velocity such that a person in the space may perceive it as if it was being blown. A further disadvantage is that if the space is cold there is no provision for inflow of warm air into the space in such a way that temperature gradients in the space are not increased.

Summary of the invention

An object of the present invention is to propose a method and a device for minimising cold draught in a space.

A further object of the invention is to propose a method and a device for providing a more effective ventilation of a space. A further object of the invention is to propose a method and a device which are cost- effective as compared with traditional technology for ventilation of a space.

The aforesaid and other objects according to the invention are achieved by the method described in the introduction and the device described in the introduction being provided with the characteristics indicated by claims 1 and 10. Advantages achieved with a method and a device according to the characterising parts of claims 1 and 10 respectively are that a more effective ventilation of a space is achieved while at the same time cold draught is reduced.

^' . Preferred embodiments of the method and the device according to the invention further have the characteristics indicated by subclaims 2 - 9 and 11 - 19. According to an embodiment of the method, the recirculation of the room air entails flow of room air from the space into the device through the first battery's first throughflow area and temperature exchange with a heating circuit disposed in the battery. Room air is

drawn up through the battery and into the device by induction effect. A result of this is that room air can thus exchange temperature with the battery, thereby making it possible for part of the room air to be at a higher temperature after passing through the battery.

According to a further embodiment of the method, the recirculation of the room air entails flow of room air from the space into the device through the first battery's first throughflow area and temperature exchange with a cooling circuit disposed in the battery. A result of this is that room air can thus exchange temperature with the battery, thereby making it possible for part of the room air to acquire by temperature exchange with the battery a lower temperature from passing through the battery. According to an embodiment, the temperature in the cooling circuit can be regulated in such a way that the amount of temperature exchange can be regulated from partly cooling to being inactive and hence not exchanging temperature with the room air flowing through the battery.

According to a further embodiment of the method, the recirculation of the room air entails flow of room air from the space into the device through a second throughflow area in the first battery and temperature exchange with at least one heating circuit and/or cooling circuit disposed in the first battery. A result of this is therefore that part of the room air entering the device may have been cooled and/or heated in order to be mixed inside the device with room air to provide output air with a temperature which is determined by how much temperature exchange takes place between a battery and room air flowing through the battery. Tempered portions of room air in the device may thereafter flow out in various directions into the space, whereby the device will have first output air flowing out in a first output air direction at a first temperature and second output air flowing out in a second output air direction at a second temperature in a second output air direction.

According to a further embodiment of the method, the recirculation of the room air entails flow of room air from the space into the device through a second throughflow area in a second battery in the device and temperature exchange with at least one heating circuit and/or cooling circuit disposed in the second battery. A result of using two parallel batteries disposed alongside one another is that it is easy to provide a plurality of possibilities for how to use respective battery temperature exchange of a throughflow of room air. Inter alia, both of the batteries may be allowed to cool, or one battery may be used for cooling and one for heating, or both batteries may be used for heating.

According to a further embodiment of the method, the recirculation of the room air entails flow of a first volume of room air through the first throughflow area being smaller than flow of a second volume of room air through the second throughflow area. A result of this distribution is that there will be too much heated air in the output air from the device and hence an insufficient amount of cooled output air which can sink down towards the floor and thereby provide sufficiently effective remixing of the room air. Too great a volume of heated

output air in the space may result in the warm output air lying like a blanket in the space above old room air, thereby hindering effective mixing and changing of the room air.

According to a further embodiment of the method, the flow of output air in the first output air direction entails accumulation of the output air in a zone adjacent to an upper region of the cooling surface. The accumulation of output air in this zone entails cooling of the output air in the zone and continuous movement of the cooled output air in a direction from the zone to the floor, along the cooling surface. The flow of output air in the second output air direction entails flow of the output air from the device towards the wall surface and, at the wall surface, continuous movement of the output air along the respective wall surface towards the floor. A result of the heated output air accumulating in said zone is that it is thereby caused to be cooled slowly by the cooling surface. The cooled air thereafter moves continuously down towards the floor along the cooling surface while at the same time the zone is continuously replenished with new output air from the first output air direction of the device. At the same time on other surfaces, cooled or unaffected tempered air will flow down along the wall surfaces towards the floor and move across the floor towards the cooling surface. The air moving towards the cooling surface will prevent cooled air from the cooling surface from being caused to flow across the floor. Instead, there will be a remixing of the air from the cooling surface and the other wall surfaces. This method prevents so-called cold draught, i.e. a user in the room having the sensation that there is blowing in the room. A cooling surface in a space may take the form of, for example, a window.

Air which is cold is heavier than air which is heated or warm. This means that cold air in a space will endeavour to move downwards, while warm air in the space will tend to rise upwards. This fact is used in the present invention by cooled output air being caused to flow out from the device towards wall elements within the space. The cooled output air entering the space will be colder than the room air in the space and therefore be heavier. Owing to the greater weight of the cooled output air flowing towards the wall elements, the cooled output air from the device within the space will not move downwards towards the floor at the wall elements. If the device is situated in the ceiling of a large room, the cooled air may already begin moving down towards the floor before it has reached the wall elements, owing to its being heavier than the room air in the space.

According to a further embodiment of the device, a second throughflow area is disposed in the first battery. In the battery, the first and second throughflow areas are disposed alongside one another. The first and second throughflow areas together constitute a surface which may be likened to a common throughflow area. The throughflow areas face towards the room, and the recirculating room air flows up and into the device through them.

According to a further embodiment of the device, part of the first battery with the first throughflow area comprises a heating circuit configured to exchange temperature with the

recirculating room air. Air which passes through this part of the battery is drawn up and into the device by induction effect. Within the device, the heated room air is mixed and combined with the intake air which has come into the device. The inflow of intake air into the device results in above atmospheric pressure inside the device relative to the air pressure in the space. The above atmospheric pressure in the device provides an effective means by which the intake air in the device can be allowed to pass through a flow director in the device, resulting in a flow of intake air through the device which mixes with the recirculating room air to provide output air which is led out into the space via directing means on the device. The portion of the battery which warms the recirculating room air flowing through is situated on one side of the battery. This means that the recirculating room air flowing into the device on that side of the battery also flows out from the device into the space in a mixture with intake air on the same side of the device.

According to a further embodiment of the device, part of the first battery with the second throughflow area comprises a cooling circuit configured to exchange temperature with the recirculating room air. The temperature in the cooling circuit can be regulated in such a way that the latter can be caused to exchange temperature with the room air by absorbing heat from the room air in varying amounts, or to be inactive so that no temperature exchange with the room air takes place. In the latter case, only room air flows through the battery in order thereafter to be combined and mixed with the intake air to provide a joint outflow of output air.

According to a further embodiment of the device, the first throughflow area is smaller than the second throughflow area. A result of this is that a larger volume of cooled room air than volume of heated room air can enter the device. This distribution means that the volume of heated air in the output air from the device will not exceed the volume of cooled air in the output air from the device. Too large a volume of heated output air into the space might result in the warm output air lying like a blanket in the space above old room air, with consequent hindrance to effective mixing and changing of the room air.

According to a further embodiment of the device, a second throughflow area is disposed in a second battery disposed in the device, which second battery comprises a heating circuit or cooling circuit configured to exchange temperature with the recirculating room air through the battery. In addition to the effect already mentioned above of a second battery, this embodiment has inter alia an advantage in making it possible to manufacture two identical batteries with intake pipes suited to only one type of heat-exchanging liquid flow. The manufacturing process for the batteries is thus simplified, since each battery will be usable for throughflow of either a cooling medium or a heating medium for temperature exchange with a room air throughflow

According to a further embodiment of the device, the battery comprises at least one first pipe section and at least one second pipe section which extend through the battery at at least two different levels relative to ceiling or floor, run parallel with one another through the battery and are configured to lead at least one first medium through the battery at at least one first temperature for temperature exchange with room air flowing through the battery. Moreover, the flow in the respective pipe sections can be regulated to either shut off flow through a pipe section or open up flow through a pipe section. The pipe sections being disposed at different levels in the battery makes it possible to regulate the temperature in the battery at different levels. An advantage of this is that the throughflow distance travelled by room air flowing through the battery can therefore be regulated.

According to a further embodiment of the device, the heating circuit is disposed in the battery in a first plane which extends between two second planes in which the cooling circuit is disposed. The planes run horizontally in the device and substantially parallel both to one another and to ceiling and floor. The heating circuit is positioned on one side, one portion, of the battery and extends in a first throughflow area in the battery. The cooling circuit according to this embodiment is positioned across the whole throughflow area of the battery in a second throughflow area. As seen from the space looking up into the device, the second throughflow area overlaps the first throughflow area. A result of the second throughflow area extending across the whole battery is that the whole battery's throughflow area can therefore be used for cooling, since the cooling circuit extends across the whole battery's throughflow area. The cooling circuit can be regulated in such a way that it is only active for cooling in the portions/regions of the battery which have no heating circuit.

According to a further embodiment of the device, the device is configured to be disposed in the ceiling in such a way that the heating circuit is at a distance from the cooling surface which is shorter than the distance from the cooling circuit of the device to said cooling surface. Such an orientation means that heated outflow is directed towards the cooling surface and that cooled outflow is directed towards the other wall surfaces, thereby optimising the ventilation effect as compared with traditional ventilation devices.

Brief description of the drawings

A preferred embodiment of the device and the method according to the invention is described in more detail below with reference to the attached schematic drawings, which only show the parts necessary for understanding the invention.

Fig. 1 depicts a device comprising a battery for ventilation of a space. Figs. 2a-c depict three views of a battery configured for being used in a ventilation device.

Figs. 2d-e depict two views of a battery configured for being used in a ventilation device.

Fig. 3 depicts a device comprising two batteries for ventilation of a space. Fig. 4 depicts a method of ventilating a space with a traditional ventilation device. Fig. 5 depicts a method of ventilating a space with a ventilation device according to the invention.

Detailed description of various embodiments of the invention

Fig. 1 depicts a device (1 ) comprising receiving means (2), which receiving means is adapted to being connected to an intake air element (H). The intake air element (H) forms part of a system to which the device (1 ) is connected, which system supplies and conveys intake air (6) to the device (1 ). The device (1 ) further comprises a first battery (3a) which itself comprises a first throughflow area (4a). Part of the device (1 ) which is adjacent to the space (A, see Fig. 5) comprises directing means (5). The purpose of the directing means (5) is to direct a mixture of intake air (6) and recirculating room air (7) into the space (A). This mixture is called output air (8). The directing means (5) is adapted to directing the output air (8) into the space in at least one first output air direction (9a) and at least one second output air direction (9b). The device according to Fig. 1 is fitted in a ceiling (B) in the space. According to an embodiment, the directing means (5) may take the form of a sunlike directing means (not depicted in the diagrams) whereby the output air (8) is directed 360 ^° out from the device (1 ) into the space (A). According to an alternative embodiment, the output air (8) is directed to flow in four directions out from the device (1 ) towards surrounding wall elements in and to the space (A), whereby two mutually adjacent directions form substantially between them an angle of about 90 degrees. Figs. 2a - 2c depict a first battery (3a) in three different views.

Fig. 2a depicts a view of the battery (3a) as seen from in front looking at a heat transfer surface on a first plate disposed in the battery (3a) with downstream plates disposed after one another. Fig. 2a shows a heating circuit (10) and a cooling circuit (11 ).

Fig. 2b depicts a view of the battery (3a) from the side, with the short end of each plate in the battery (3a) pointing towards the observer. The view depicted in Fig. 2b shows only the cooling circuit (11). This is because in the diagram the heating circuit (10) is disposed behind the cooling circuit (11 ) and is therefore not visible in the view depicted. Fig. 2b shows first pipe sections (12a) and second pipe sections (12b) extending through the battery (3a) at least two different levels and parallel with one another. Fig. 2c depicts a view of the battery (3a) as seen from below. This portion of the battery (3a) is the portion which faces in towards the space (A) when the battery (3a) is disposed in the ceiling (B). Fig. 2c shows the second pipe sections (12b) extending through

the battery. The first pipe sections (12a) are not visible in Fig. 2c because they are masked in the diagram by the second pipe sections (12b). The throughflow area of the battery (3a) comprises a first throughflow area (4a) and a second throughflow area (4b). The throughflow areas (4a, 4b) are disposed alongside one another in the battery and for an observer they may together resemble or be perceived as one throughflow area. The first throughflow area (4a) is smaller than second throughflow area (4b). The heating circuit (10) extends in the first throughflow area (4a). The cooling circuit (11) extends in the second throughflow area (4b).

Each pipe section (12a, 12b) is configured to have flowing through it either a heating or a cooling medium, e.g. water or some other flowing liquid which can convey and exchange temperature with air which flows through the battery (3a).

The first throughflow area (4a) can be regulated in that the number of pipe sections (12a, 12b) which have a heating medium flowing through them can be regulated to be either more or fewer pipe sections (12a, 12b). This is regulated by flow through the respective pipe sections (12a, 12b) being governed by an element which can either open up or shut off flow in pipe sections (12a, 12b). The second throughflow area (4b) can be regulated in a similar manner.

Figs. 2d - 2e depict an alternative embodiment of a first battery (3a) in two different views. Fig. 2d depicts a view of the battery (3a) as seen from in front looking at a heat transfer surface on a first plate disposed in the battery (3a) with downstream plates disposed one after another. Fig. 2d shows a heating circuit (10) and a cooling circuit (11). The heating circuit (10) is disposed in the battery (3a) in a first plane (I). The first plane (I) extends between two second planes (II) in which the cooling circuit (11 ) is disposed. Fig. 2d shows the respective pipe sections for each circuit (10, 11 ) extending straight into the diagram, which means that what the diagram shows is ends of the pipe sections of the circuits (10, 11 ).

Fig. 2e depicts a view of the battery (3a) as seen from below in the same way as described above for Fig. 2c. This embodiment according to Fig. 2e depicts a first throughflow area (4a) and a second throughflow area (4b). The diagram shows the first throughflow area (4a) disposed below, for an observer in the space above, the second throughflow area (4b), but for an observer in the space the second throughflow area (4b) only is visible.

Each pipe section is configured to have flowing through it either a heating or a cooling medium, e.g. water or some other flowing liquid which can convey and exchange temperature with air which flows through the battery (3a).

The respective first and second throughflow areas (4a, 4b) can be regulated in that the number of pipe sections which have a heating medium flowing through them can be regulated to be either more or fewer pipe sections. This is regulated in the same manner as previously described. Fig. 3 depicts an embodiment of the invention in which the device (1 ) comprises a second battery (3b). This second battery (3b) is disposed parallel with the first battery (3a). The first and second batteries (3a, 3b) are of mutually similar construction. Each battery (3a, 3b) comprises at least one circuit for being able to either heat or cool air which flows through the respective battery (3a, 3b) and into the device (1 ). Fig. 4 depicts a limited space ventilated in a traditional manner by known ventilation device fitted in the ceiling of the space, which device has air flowing out from it in a number of directions into the space at a temperature. A result of using such known device and such traditional method is that the ventilation in a space is thereby not optimised. This is because the air which comes out from the device lies like a blanket at a level in the space above the original air still present in the space. The "blanket" is formed because the original air still present is somewhat colder than the air which flows out from the device. The result is that the new air lies on top of the original air in the space.

Fig. 5 depicts a space (A) ventilated by a device (1 ) according to the invention. The space (A) comprises ceiling (B), floor (C), a cooling surface (D) and at least two wall surfaces (E, F). Part of a third wall surface (G) appears in the diagram. This third wall surface (G) is illustrated to show that the space (A) comprises surfaces (D-G) on all four sides of the space. However, to be able to illustrate the inside of the space (A), the third wall surface (G) is not depicted in its entirety on the space (A).

During operation, the device (1) is supplied with a flow of intake air (6). Recirculating room air (7) flows by induction effect up and into the device (1 ) through the battery (3a, see Fig. 1 ). After passing through the battery (3a), the recirculating room air (7) is guided out towards the sides inside the device (1 ) by the intake air (6) flowing into and through the device (1 ) via the receiving means (2). Inside the device there is an air flow director through which the intake air (6) passes before it combines with the recirculating room air (7). The air flow director inside the device is configured to cause the intake air (6) to flow towards directing means (5). Directing means (5) are disposed on parts of the device (1) which are adjacent to the space (A). A mixture of intake air (6) and recirculating room air (7) flows through directing means (5) in at least one first and one second output air direction (9a, 9b). The intake air (6) which flows to the device (1 ) enters the device (1 ) at a temperature which will be lower than the room air in the space (A).

The battery (3a) comprises a first throughflow area (4a) through which part of the recirculating room air (7) flows. This first throughflow area (4a) is disposed on one side of

the battery (3a), and the recirculating room air (7) which flows up through the first throughflow area (4a) exchanges temperature with part of the battery (3a) which comprises a heating circuit (10). The recirculating room air (7) enters the device (1 ) in the portion of the device (1 ) which is situated nearest to a cooling surface (D, see Fig. 5) in the space (A). Inside the device (1 ) the heated recirculating room air (7) is combined and mixed with the intake air (6) as a result of the air flow director inside the device (1) causing the intake air (6) to flow partly towards the recirculating room air (7) through the battery and partly towards the directing means (5) on the device (1 ), thereby combining the recirculating room air (7) and the intake air (6) to provide output air (8) in a first output air direction (9a) towards the cooling surface (D). The output air (8) which flows out from the device (1 ) in the first output air direction (9a) will be at a temperature which is higher than the room air in the space (A).

Through a second throughflow area (4b) disposed alongside the first throughflow area (4a) on the battery (3a), recirculating room air (7) flows up through said second throughflow area (4b), parallel with the recirculating room air (7) through the first throughflow area (4a). In part of the battery (3a) with the second throughflow area (4b), the recirculating room air (7) exchanges temperature with a cooling circuit (11 ). inside the device (1 ), the recirculating room air (7) which has been cooled, or which remains unaffected if the cooling circuit is inactive, is combined and mixed with the intake air (6) as a result of the air flow director inside the device (1 ) causing the intake air (6) to flow partly towards the recirculating room air (7) which flows up through the second throughflow area (4b) of the battery (3a) and partly towards the directing means (5) on the device (1 ), thereby combining the recirculating room air (7) and the intake air (6) to provide output air (8) in a second output air direction (9b) towards at least one wall surface (E, F, G). The output air (8) which flows out from the device (1 ) in the second output air direction (9b) will be at a temperature which is lower than or equal to the room air in the space (A).

Within the space (A, see Fig. 5), output air (8) flowing in a first output air direction (9a) towards the cooling surface (D) has been heated and will be at a higher temperature than the room air. At an upper region of the cooling surface (D), the heated output air (8) accumulates in a zone (13), a so-called temperature zone. The zone (13) is adjacent partly to the cooling surface (D) and partly to the ceiling (B). The cooling surface (D) has a surface temperature which is lower than the surface temperatures of the other wall surfaces (E, F, G) in the space (A). Said cooling surface (D) cools the heated output air (8) in the zone (13). The output air (8) which is adjacent to the cooling surface (D) and is thus cooled therefore moves downwards along the cooling surface (D) towards the floor (C). The fact that the zone (13) is only adjacent to one side which cools the output air (8) means that the cooling of the output air (8) takes place rather slowly, while at the same time the zone (13) is continuously replenished with new heated output air (8). The result is a controlled and continuous flow of

cooled air down towards the floor (C), with consequent reduction in cold draught. The room air is hindered by the output air moving down in the form of a thin film towards the floor (C) from the zone (13) along and across the cooling surface (D), whereby the room air is prevented from being cooled by the cooling surface (D) and the so-called cold draught is therefore minimised.

In the space (A), output air (8) flows in a second output air direction (9b) towards at least one of the other wall surfaces (E, F, G), preferably towards all three wall surfaces (E, F, G). The output air (8) in the second output air direction (9b) is cooled and will be at a temperature which is lower than or equal to the room air in the space (A). The result is that this cooled output air (8) will flow down along the respective wall surface (E, F; G) towards the floor because it is heavier than the room air. The result is a more effective ventilation effect and a low and optimised temperature gradient because temperature differences between floor and ceiling are minimised.

The invention is not limited to the embodiment depicted but may be varied and modified within the scope of the claims set out below, which have been partly described above.