Patent Description:
Ventilating (V) is the process of changing or replacing air in any space to provide high indoor air quality, for example to control temperature, replenish oxygen, or remove moisture, odors, smoke, heat, dust, airborne bacteria, and carbon dioxide. Ventilation is used to remove unpleasant smells and excessive moisture, introduce outside air, to keep interior building air circulating, and to prevent stagnation of the interior air. Ventilation includes both the exchange of air to the outside as well as circulation of air within the building. It is one of the most important factors for maintaining acceptable indoor air quality in buildings. Methods for ventilating a building may be divided into mechanical or forced and natural types.

Air condition (AC) is the process of altering the properties of air within a space to desired conditions, those properties primarily being temperature and humidity. The aim is typically to distribute conditioned air into a space to improve the thermal comfort (lowering or raising the temperature) and air quality.

The current single room air conditioners for environments are typically arranged into or on the ceiling of an air-conditioned room. In an air conditioner, there is a heat exchanger or radiator in which heat exchanging medium is arranged to circulate in a coil covered by lamellas or fins that distribute the incoming air evenly into the heat exchanger. The heat exchanger may be arranged into a frame, and it is typically covered by detachable cover panel, which can be removed for cleaning the air conditioner. Filters are used in some installations to prevent the heat exchanger from clogging. Secondary filters are used in some installations to ensure the quality of air reentering the space. Fans or induction of fresh air are used to circulate the air in and out of the air conditioner.

Air conditioners require periodic specialist cleaning and maintenance, such as vacuuming of the heat exchanger to ensure high level of hygiene within the room or space. Additionally, air conditioners comprising a filter through which air is led prior to its conditioning with the heat exchanger require regular changing of filters. The specialist cleaning is an additional cost to the building owner and it typically causes also that room subject to such specialist cleaning need to be taken out of its' normal use for the period of cleaning. In rooms, where especial hygiene requirements are set, such as hospital patient rooms, additional costs for the building owner is generated as the room is thoroughly cleaned after specialist cleaning.

A typical air conditioner is disclosed for example in document <CIT>, which device comprises large holes for the air entering the device. As the holes for the suction air are large, dirt and other impurities may enter inside the device. <CIT> discloses a cooling system for separating debris from atmospheric air through use of a blower and a separation chamber, and a work vehicle comprising such cooling system.

An object of the present invention is to provide an air conditioner for conditioning air in a room. The object is achieved by the features of the independent claim.

The air conditioner comprises a frame; a cover panel for reducing the amount of dust and other impurities entering the inside of the frame and from there when the device is in operation, comprising a perforated area arranged into it, the perforated area comprising perforations for air flow entering the apparatus, each perforation having a diameter; and a heat exchanger arranged within the frame and comprising at least one heat exchanger coil, lamellas, and openings arranged between each adjacent lamella, each opening having a length. A ratio of the length of the openings and the diameter of the perforations is at least <NUM>:<NUM>, and the frame is installable into the ceiling of the room, either directly into the ceiling structure so that the frame is wholly or partially embedded into the ceiling structure so that only the cover panel is visible, or a part of the frame and the cover panel is visible, or the air conditioner is installable to hang or to otherwise extend from the ceiling.

The aforementioned implementation embodiments offer a solution to the problems and disadvantages of the known prior art. Other technological benefits of the present invention become evident to a person skilled in the art from the following description and the claims. The numerous embodiments of implementing the present invention achieve only a part of the presented advantages. The invention is defined in the claims.

The attached figures illustrate examples of embodiments of the present invention, and together with the above general description and the detailed current embodiments help to explain, by way of examples, the principles of the invention.

According to an embodiment, as depicted in <FIG>, the apparatus <NUM>, which can be used for conditioning the air in a room or space <NUM> such as a patient room, for example by heating or cooling the air, comprises a frame <NUM>, a cover panel <NUM> and a heat exchanger <NUM>. The frame <NUM> may be essentially a rectangular box or casing with two longer sides and two shorter end sides, which sides define an internal space <NUM> (as shown in <FIG>) or opening into which the heat exchanger <NUM> can be arranged. The frame <NUM> may also have a square form having four sides of equal lengths, or it can be circular with one continuous side. The opening and the heat exchanger <NUM> arranged therein is covered by the cover panel <NUM>. The frame <NUM> may have sides that are arranged at an angle deviant of vertical, to allow directing a flow of conditioned air <NUM> back into the space <NUM>. There may be arranged gaps or open spaces between the cover panel <NUM> and the sides of the frame <NUM>.

According to an embodiment, supply air flow <NUM> of air, which can be pre-cleaned or purified prior to its conduction to the apparatus <NUM>, is led or conducted into the apparatus <NUM> via a supply duct <NUM>, which opens into the internal space <NUM> of the apparatus <NUM>, as shown in <FIG>. In <FIG> the supply duct <NUM> is not shown for the sake of clarity, but it is to be understood that a supply air flow is led into the apparatus <NUM> via at least one supply air duct <NUM> connected into the apparatus <NUM> in a suitable manner and opening into the internal space <NUM> of the apparatus <NUM> to conduct and uniformly distribute the supply air flow <NUM> into the apparatus to be mixed with the air flow <NUM> entering into the apparatus <NUM> from the space <NUM> and being conditioned as it passed through the heat exchanger <NUM>. In effect, the supply air flow draws the air flow <NUM> into the internal space <NUM> of the apparatus <NUM> by way of induction. The air flow <NUM> mixed with the supply air flow <NUM> flows back into the space <NUM> as conditioned clean air flow <NUM>. According to an embodiment, the apparatus <NUM> may be an active AC apparatus intended to be both a supply air terminal apparatus and an air conditioning apparatus integrated into one combination.

The cover panel <NUM> comprises a perforated or slotted area <NUM> arranged into it. The perforated area <NUM> may cover the whole or part of the surface area of the cover panel <NUM>. In the embodiment of <FIG>, the perforated area <NUM> is arranged to extend longitudinally over the whole length of the cover panel <NUM>, leaving two unperforated areas at the sides of the cover panel <NUM>, again in longitudinal direction. The perforated area <NUM> comprises perforations <NUM> which may have a circular form, as illustrated in <FIG>. The perforations <NUM> are arranged uniformly distributed onto the perforated area <NUM>. According to other embodiments, the perforations <NUM> may have a form other than circular, such as squares or rectangles, may be used as well. The perforations <NUM> can be seen more clearly in the enlargement A' or the area A in <FIG>.

Each perforation <NUM> has an open area with a diameter D which is the measurement between two opposing sides of the perforation. In an embodiment where the perforations <NUM> are circular, the diameter D is the diameter of each circular perforation. In an embodiment where the perforations <NUM> have a square form, the diameter D is the distance between two opposing sides of each square perforation. In an embodiment where the perforations <NUM> have a rectangular form, the diameter D is the shortest distance between two opposing sides of the rectangular perforation. The diameter D can vary between <NUM>- <NUM>,<NUM>. For example, the diameter can be <NUM>,<NUM>. In an embodiment, the diameter may be <NUM>,<NUM>; <NUM>,<NUM>; <NUM>,<NUM>; or <NUM>,<NUM>.

The cover panel <NUM> reduces the amount of dust and other impurities entering the inside of the frame <NUM> and from there, from circulating back into the clean room <NUM>. This is due to the chosen diameter D of the perforations <NUM>. Further, the cover panel <NUM> can be opened or removed from the frame <NUM> to enable cleaning and maintenance of the inside of the frame <NUM> and the heat exchanger <NUM>. In an embodiment, the cover panel <NUM> is detachably attached into the frame <NUM> so that the cover panel <NUM> may be wholly removed. In another embodiment (<FIG>), the cover panel <NUM> is pivotably connected to the frame <NUM> from its one edge (110a, 110b), so that the cover panel <NUM> may be opened without removing it wholly. The pivotal connection may comprise hinges or other such turning joints. In addition or alternatively, the cover panel <NUM> can be easily cleaned from outside the apparatus <NUM> with conventional cleaning equipment during the normal day-to-day cleaning operations of the room or space <NUM>, i.e. no specialized cleaning operations or personnel are needed. Thus cover panel <NUM> can be made more hygienic.

By choosing a diameter D of the perforations <NUM> so that the front panel <NUM> is able to significantly reduce or hinder the migration of dust and other particles with air flow <NUM> into the inside of the frame <NUM>, the apparatus <NUM> may be arranged to remove impurities from air flow <NUM> entering the apparatus <NUM>. As further discussed later on in the description, lamellas of the heat exchanger <NUM> have greater distance so as to reduce the migration of dust and other particles with air flow <NUM> into the inside of the frame <NUM>.

The heat exchanger <NUM>, which can be seen for example in <FIG>, comprises at least one heat exchanger coil <NUM> in which a heat exchange medium is arranged to circulate. In an embodiment the heat exchanger <NUM> utilizes dry heat transfer in order to eliminate or minimize the risk of condensation within the apparatus <NUM>, and thereby avoiding creating favorable conditions for microbial growth, as well as avoiding the use of a filter for coil protection. Also other heat transfer types may be utilized.

The heat exchanger <NUM> further comprises a number of lamellas <NUM> and openings <NUM> arranged between each adjacent lamella <NUM>. Each of the openings <NUM> have a length L, as measured from one lamella to the next as can be seen in the enlargement B' of the area B in <FIG>. The length L can vary between <NUM> - <NUM>. For example, the length L can be <NUM>. In an embodiment, the length L may be <NUM>,<NUM>; <NUM>,<NUM>; <NUM>,<NUM>; <NUM>,<NUM>; or <NUM>,<NUM>. A greater length L of the openings <NUM> reduces the amount of dust and other impurities accumulating to the lamellas <NUM> and openings <NUM> thereof. The heat exchanger <NUM> may be more hygienic. Need to maintenance may be reduced.

According to an embodiment, the heat exchanger <NUM> may be detachably attached into the frame <NUM> to enable cleaning and maintenance of the inside of the frame <NUM> and the heat exchanger <NUM>. In an embodiment, the heat exchanger <NUM> is detachably attached to the frame <NUM> so that the heat exchanger <NUM> may be wholly removed. In another embodiment, the heat exchanger <NUM> is pivotably connected to the frame <NUM> from one of the sides 130a of the heat exchanger <NUM>, so that the heat exchanger may be removed partially from within the frame <NUM>. The side 130a may here denote for example the heat exchanger coil <NUM>, which can be hinged or otherwise pivotally connected to the frame <NUM>. The pivotal connection may comprise hinges or other such turning or pivot joints. Also in the case of a pivotal connection, the heat exchanger <NUM> may be wholly removed from the frame <NUM> by removing the pivot part from its housing.

According to an embodiment, the length L of the openings <NUM> and the diameter D of the perforations <NUM> may be chosen to <NUM>) ensure air conditioning for the clean room <NUM>, and <NUM>) reduce the circulation of dust and other impurities from the room or space <NUM> into the apparatus <NUM> and from there back into the clean room or space <NUM> with the flow <NUM> of conditioned air. According to an embodiment, a ratio of the length L of the openings <NUM> and the diameter D of the perforations <NUM> may be at least <NUM>:<NUM>. The aforementioned ratio may vary for example between <NUM>,<NUM>:<NUM> to <NUM>,<NUM>:<NUM>. In other embodiments, the ratio may be larger, for example <NUM>,<NUM>:<NUM> or <NUM>,<NUM>:<NUM>. In an embodiment, the ratio is <NUM>,<NUM>:<NUM>, in which case the length L of the openings <NUM> may be <NUM>,<NUM> and the diameter D of the perforations <NUM> may be <NUM>,<NUM>.

In an experiment, it was shown that an apparatus <NUM> according to an embodiment comprising a cover panel <NUM> with small diameter, for example <NUM>, perforations <NUM> may be significantly more efficient in preventing dust from entering the inside of the frame <NUM> than a conventional cover panel comprising larger diameter perforations. The cover panel <NUM> of the apparatus <NUM> and the heat exchanger <NUM> accumulated around <NUM> % more dust on its room <NUM> facing surface <NUM> than a conventional panel and a conventional heat exchanger used as a reference in dusting experiments conducted over several days, where the dust accumulation was measured as a weight-% of controlled dust addition into the room <NUM>. In the experiment, the total amount of dust introduced into the room <NUM> corresponded to the amount of dust accumulating into a room in normal use over a period of approximately two years. Further, it was found that less dust was collected in the openings <NUM> with a greater length L (<NUM>) than in the openings <NUM> with a smaller length (<NUM>). In the <NUM> lamella openings <NUM>, dust was mainly collected in the ends of the lamellas (in longitudinal direction of the lamellas), whereas in the <NUM> lamella openings, dust was evenly collected into the entire length of the openings (in longitudinal direction of the lamellas), thus making the conventional heat exchanger lamellas more sensitive to clogging and more difficult to clean.

According to an embodiment, to further enhance the properties of the apparatus <NUM> in use in rooms and spaces, the apparatus <NUM> may have antibacterial properties. For example, the frame <NUM>, the cover panel <NUM>, the heat exchanger <NUM>, or all of them, may have antibacterial properties. In an embodiment, the heat exchanger <NUM>, the frame <NUM> and/or the cover panel <NUM> may be treated with an antibacterial surface treatment such as paint or other coating. Examples of this kind of surface treatment comprise silvering or silver plating, or treating the surface with a copper-based paint. The aforementioned parts may also be made from an antibacterial material. The heat exchanger coil <NUM> may be made from an antibacterial material such as copper. Also the heat exchanger coil <NUM> may be treated with a surface treatment such as the aforementioned silvering or silver plating or painting with a copper-based paint. According to an embodiment, the apparatus <NUM> may also provide an enhanced antibacterial performance of the heat exchanger <NUM> in use, because the accumulation of dust into the large surfaces of a conventional heat exchanger will impair the effect of the antibacterial surface.

In <FIG>, which a cross-directional view C of an apparatus <NUM> of <FIG> according to an embodiment, is illustrated how the air flow <NUM> from the space <NUM> is received into the apparatus <NUM> by means of induction through the perforations <NUM> of the perforated area <NUM> of the cover panel <NUM>. Further, a supply air flow <NUM> is led into internal space <NUM> of the apparatus <NUM> via a supply air duct <NUM>. The supply air flow <NUM> may be pre-cleaned, pre-conditioned or otherwise treated prior to its conduction into the supply air duct <NUM> and the apparatus <NUM>. The amount of dust and other impurities that enter into the internal space <NUM> of the apparatus <NUM> with the air flow <NUM> is reduced (or diminished) by the small diameter perforations <NUM>. The air flow <NUM> enters the heat exchanger through the openings <NUM> (not shown in <FIG>) between the lamellas <NUM>, and is conditioned in the heat exchanger <NUM>, is mixed with the supply air flow <NUM>, and the mixed flow is then led back into the room <NUM> as a clean air flow <NUM> from which at least a part of the dust and other impurities have been removed. Appropriate length L of the openings <NUM> may prevent dust and impurities for sticking or accumulating to the heat exchanger <NUM>.

In an embodiment, as illustrated in <FIG>, the apparatus according to the invention is a fan-coil air conditioner <NUM>'. The apparatus <NUM>' comprises a frame <NUM>' with an inner space <NUM>' into which a heat exchanger <NUM>' and a fan <NUM> are arranged. Air flow <NUM> is received into the apparatus <NUM>' through a cover panel <NUM>' comprising a perforated area <NUM>'. In a typical fan-coil air conditioner, the air flow <NUM> is led into the internal space <NUM> via a filter preceded with a sparse louvre. In an embodiment according to the invention, the air flow <NUM> is led into the apparatus <NUM>' via the perforated area <NUM>' of the cover panel <NUM>' alone, i.e. no filter and/or a louvre is employed, and the cover panel <NUM>' may replace the louvre and the filter. A supply air flow <NUM> (which may be prefiltered or otherwise pretreated air) is led into the apparatus <NUM>' from an outside source via a supply air duct (not shown).

The air flows are conditioned in the heat exchanger <NUM>' and led back into the clean room <NUM> with the help of the fan <NUM>. The fan may be isolated from the internal space <NUM>' by screens or cut-off wall <NUM> which prevent internal back-circulation of conditioned air within the apparatus <NUM>'. Dust and other impurities that may migrate into the apparatus <NUM>' with the air flow <NUM> are effectively collected on the outside surface (as viewed from the room <NUM>) of the cover panel <NUM>', which is detachably attached into the frame <NUM>' in the same manner as previously explained in connection with the first embodiment of the invention. In the apparatus <NUM>', the air flow <NUM> is received from and led back to the room <NUM> by mechanical ventilation. However, there is no need to use any filters or filtering equipment in the apparatus <NUM>' to ensure an acceptable level of cleanliness in the air flow <NUM>, in contrast to conventional fan-coil apparatuses due to the diameter D of the perforations in the perforated area <NUM>' of the cover panel <NUM>', similarly as what has been explained above in connection with the other embodiments. Furthermore, the length L of the openings of the lamellas of the heat exchanger <NUM>' may be according to the embodiments to prevent dust and impurities from sticking and accumulating to the lamellas and the openings.

The frame <NUM> may be installed into the ceiling <NUM> of the room <NUM>, either directly into the ceiling structure so that the frame <NUM> is wholly or partially embedded into the ceiling structure so that only the cover plate <NUM> is visible, or a part of the frame <NUM> and the cover plate <NUM> is visible. Alternatively, the apparatus <NUM> may be installed to hang or otherwise extend from the ceiling <NUM> with any suitable mounts <NUM>, as is shown in <FIG>.

According to an embodiment, a layout and setting of apparatuses <NUM> within a space which is a room <NUM>, is described. The object may be to produce more consistent level of cleanliness and thermal environment within the room <NUM> where human operations are practiced (<FIG>), as well as provide apparatuses for conditioning air which can be easily cleaned. The room <NUM> may be a hospital room or a patient room, an office space or room, a hotel room, or any other space where air conditioning is needed.

In the room <NUM>, at least some of the apparatuses used to treat the air are apparatuses <NUM>, <NUM>' according to the invention. The apparatuses <NUM>, <NUM>' are air conditioners. An apparatus <NUM> may be installed into the ceiling <NUM> of the clean room <NUM> either by embedding it wholly or partially into the ceiling or by mounting it on the ceiling to hang or otherwise extend downwards from the ceiling at a position most convenient to the critical operations of the clean room <NUM>. Apparatuses may also be installed at the walls or into, or on the floor.

In an embodiment, the room <NUM> is a patient room, and the critical healing or other operations take place at a patient bed <NUM>, where it is crucial that the personnel and the patient to receive a flow of conditioned air to ensure comfort and an acceptable level of cleanliness, for example air flow with a suitable temperature and velocity with as little contaminants (either particles such as dust or fibres, or contaminants of microbial sources such as bacteria or spores). A supply air flow <NUM> of clean (pre-cleaned or prefiltered or otherwise pretreated) air may be led into the room <NUM>. Air flow <NUM> is received into the apparatus <NUM> as described earlier by induction induced by the supply air flow <NUM> and/or mechanical ventilation, conditioned in the heat exchanger <NUM> arranged inside the frame <NUM> of the apparatus <NUM>, mixed with the supply air flow <NUM> within the internal space <NUM> of the apparatus <NUM>, and led back into the clean room <NUM> as return clean air flow <NUM>. A part of the air is circulated in this manner; while a part <NUM> may be removed from the clean room <NUM> via air outlets <NUM>, of which only one is shown in <FIG>. The air outlets <NUM> may be arranged into the ceiling <NUM> or at the walls, for example near or adjacent to the ceiling <NUM>. In an embodiment, alternatively or additionally, also gravitational ventilation may be used to achieve air flow <NUM> into the apparatus <NUM>.

With the apparatus <NUM> as described earlier in connection with the embodiments, it may be ensured that a significant amount of dust and other impurities are prevented from entering the apparatus <NUM> and back into the room <NUM>, while at the same time directing enough conditioned air flow into the needed area.

A need for costly specialist cleaning or maintenance operations can be reduced on account of prolonged time between those operations. The apparatus <NUM> may be conveniently cleaned during the normal cleaning and maintenance operations for the clean room <NUM>, taking place for example once a day, or after each patient. The day-to-day cleaning may include wiping the cover plate <NUM> to remove the accumulated dust and other contaminants from the surface of the cover plate <NUM> facing the clean room <NUM>. Periodically, the apparatus may be thoroughly cleaned by removing the cover plate <NUM> and the heat exchanger <NUM>, but this specialized work or specialist cleaning operation is not necessary on a day-to-day basis. Therefore costly special work may be performed at longer intervals. The day-to-day cleaning may be performed without any special equipment or without climbing up from the floor level so normal cleaning personnel is able to execute it.

In an embodiment, the ratio of the length of the openings and the diameter of the perforations may be between <NUM>,<NUM>:<NUM> - <NUM>,<NUM>:<NUM>. In other embodiments, the ratio may be <NUM>:<NUM>; <NUM>,<NUM>:<NUM>; <NUM>,<NUM>:<NUM>; <NUM>,<NUM>:<NUM> or <NUM>,<NUM>:<NUM>.

In an embodiment, the diameter of the perforations may be at least <NUM>,<NUM>, and the length of the openings may be at least <NUM>.

In an embodiment, the diameter of the perforations may be <NUM>,<NUM> - <NUM>,<NUM>. In other embodiments, the diameter of the perforations may be <NUM>,<NUM>; <NUM>,<NUM>; <NUM>,<NUM>; <NUM> or <NUM>,<NUM>.

In an embodiment, the length of the openings may be <NUM> - <NUM>. In other embodiments, the length of the openings may be <NUM>,<NUM>; <NUM>,<NUM>; <NUM>; <NUM>,<NUM>; <NUM>; or <NUM>,<NUM>.

In an embodiment, the cover panel may be detachably attached into the frame.

In an embodiment, the cover panel may be pivotally connected to the frame from an edge of the cover panel.

In an embodiment, the heat exchanger may be detachably attached into the frame.

In an embodiment, the heat exchanger may be pivotably connected to the frame from a side of the heat exchanger.

In an embodiment, at least one of the following may have antibacterial properties: the frame, the cover panel, or the heat exchanger.

In another embodiment, the heat exchanger coil may be made from copper or painted by an antibacterial paint.

In an embodiment, an air flow may be received into the apparatus through the cover panel from a space outside the apparatus and the air flow may be led back into the space by gravitational or forced ventilation or induction.

In an embodiment, the apparatus further may comprise a fan, and an air flow may be received into the apparatus from a space outside the apparatus and the air flow may be led back into the space by mechanical ventilation.

In an embodiment in addition or alternatively, further including an internal space within the frame, into which internal space a supply air flow may be conducted.

Claim 1:
An air conditioner (<NUM>) for conditioning air in a room, comprising
a frame (<NUM>);
a cover panel (<NUM>) for reducing the amount of dust and other impurities entering the inside of the frame and from there from circulating back into the clean room when the device is in operation, comprising a perforated area (<NUM>) arranged into it, the perforated area (<NUM>) comprising perforations (<NUM>) for air flow (<NUM>) entering the apparatus (<NUM>), each perforation (<NUM>) having a diameter (D); and
a heat exchanger (<NUM>) arranged within the frame (<NUM>) and comprising at least one heat exchanger coil (<NUM>), lamellas (<NUM>), and openings (<NUM>) arranged between each adjacent lamella (<NUM>), each opening having a length (L),
wherein a ratio of the length (L) of the openings (<NUM>) and the diameter (D) of the perforations (<NUM>) is at least <NUM>:<NUM>, and
the frame (<NUM>) is installable into the ceiling (<NUM>) of the room, either directly into the ceiling structure so that the frame (<NUM>) is wholly or partially embedded into the ceiling structure so that only the cover panel (<NUM>) is visible, or a part of the frame (<NUM>) and the cover panel (<NUM>) is visible, or the air conditioner (<NUM>) is installable to hang or to otherwise extend from the ceiling (<NUM>).