Outdoor unit of an air conditioner

An outdoor unit of an air-conditioner. The outdoor unit has a casing having a front air outlet and at least one air inlet. At least one fan is located in the casing. The outdoor unit is configured such that the at least one air inlet is provided in a top section and or in a bottom section of the outdoor unit when the outdoor unit is installed in an operational position. The outdoor unit is further configured such that the at least one fan is configured to move air from the at least one air-inlet to the front air outlet or move air from front air outlet to the at least one air-inlet.

This application is a U.S. National Phase application of PCT International Application No. PCT/EP2017/082615, filed Dec. 13, 2017, which is incorporated by reference herein.

TECHNICAL FIELD

The invention relates to an air conditioner. In particular the present invention relates to a split air-conditioner and to the design of the outdoor unit of a split air conditioner.

BACKGROUND

Air conditioning is a collective expression for conditioning air into a desired state. It could be heating the air during cold periods, cooling the air during warmer periods or for cleaning the air if it contains unwanted particles. However, the expression air conditioning is most often used when emphasizing cooling. As a product, air conditioners can look and be used in various ways, but they all share the same basic technology. The air-conditioner comprises a compressor, a condenser, an evaporator, and typically also an expansion device.

There are different types of air-conditioners. One type of air-conditioner can be referred to as a split air-conditioner. In a split air conditioner, the condenser and the evaporator are located in two different separated units that are interconnected via pipes to circulate a refrigerant from one unit to the other.

Another type of air-conditioner can be referred to a Packaged Air Conditioner. A Packaged Air Conditioner (AC) can be said to be a type of self-contained system, in which all the cooling cycle components, such as the compressor, condenser, expansion device, evaporator and control system are enclosed in a single package. Among the packaged systems, the most commonly used for residential applications are the Window-type ACs, Packaged Terminal AC's (PTAC), and also Portable AC units.

The Packaged Air Conditioner has the advantages of easy installation, relatively small footprint, flexibility for heating/cooling individual rooms and low cost.

In contrast, Split Air Conditioners comprise at least two factory-made separated assemblies, designed to be used together. In a split system, the outdoor unit is separated by some distance from the indoor one(s) by means of semi rigid pipes which contain the refrigerant (at high pressure) that produces the cooling/heating effect in the system. Among other advantages, split systems can provide high efficiency ratios in a wide range of capacities and working conditions. Additionally, in split AC systems, the compressor, outdoor heat exchanger and outdoor fan can be located further away from the inside space, rather than merely on the other side of the same unit (as in PTACs or window air conditioners), achieving lower indoor noise levels.

There is a constant desire to improve air conditioners. Hence, there exists a need for an improved air conditioner.

SUMMARY

It is an object of the present invention—to provide an improved air-conditioner.

This object is obtained by an air conditioner as set out in the appended claims.

In accordance with the invention an outdoor unit of an air-conditioner is provided. The outdoor unit comprises a front air outlet and at least one air inlet. The outdoor unit further comprises at least one fan. The outdoor unit is configured such that the at least one air inlet is provided in the top section and or in the bottom section of the outdoor unit when the outdoor unit is installed in an operational position. The outdoor unit is further configured such that the at least one fan is configured to move air from the at least one air-inlet to the front air outlet or move air from front air outlet to the at least one air-inlet. Hereby it is achieved that the air can be moved through the outdoor unit without having to pass through the backside of the outdoor unit. This makes it possible to install the outdoor unit close to or directly on the outside wall of a building to facilitate installation.

In accordance with one embodiment, a compressor can be located in the center-back of the structure of the outdoor unit. Hereby a good weight distribution can be obtained also air can pass through the middle of the outdoor unit.

In accordance with one embodiment, a liquid-to-refrigerant heat exchanger can be located in the back side of the structure of the outdoor unit. Hereby a good weight distribution can be obtained also air can pass through the middle of the outdoor unit.

In accordance with one embodiment, an electronic and control box can be located in the back side of the structure of the outdoor unit. Hereby a good weight distribution can be obtained also air can pass through the middle of the outdoor unit.

In accordance with one embodiment, an air to refrigerant heat exchanger can be located at the front side of the structure of the outdoor unit. Hereby air can pass through the middle of the outdoor unit.

In accordance with one embodiment, a free space for air circulation between the backside of the structure of the outdoor unit and the air to refrigerant heat exchanger is provided. Hereby air can pass freely to the air to refrigerant heat exchanger.

In accordance with one embodiment, the outdoor unit comprises at least two fans. In particular two axial fans can be used. Hereby an improved airflow in the outdoor unit can be provided.

In accordance with one embodiment, a grill can be provided in the bottom section of the structure of the outdoor unit. Hereby air can be made to pass the bottom section of the outdoor unit and at the same time provide a base for the components inside the structure of the outdoor unit.

In accordance with one embodiment, the top section of the structure of the outdoor unit can be closed. Hereby the components of the outdoor unit can be made less exposed to rain and snow or similar.

The invention also extends to an air-conditioner comprising an outdoor unit as set out above.

DETAILED DESCRIPTION

The invention will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the invention are shown. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. For example, like or similar components of different embodiments can be exchanged between different embodiments. For example, the outdoor unit can be a conventional outdoor unit for a split air-conditioner and not an outdoor unit as described herein. Some components can be omitted from different embodiments. Like numbers refer to like elements throughout the description.

As has been realized by the inventor, conventional air-conditioners of a split type are difficult and often expensive to install. Also, conventional systems require much space. It would therefore be advantageous to provide a split air-conditioner that can be easily installed and which is more compact than conventional split air-conditioners.

FIG.1shows a schematic diagram of an embodiment of an air-conditioner100. The air-conditioner100can be said to be of a split type comprising an indoor unit101and a packaged outdoor cooling unit102. The units101,102are interconnected via an intermediate connection system103. Further, a mechanism104for installation of the air conditioner100is depicted. Also depicted is a window105where the air-conditioner100is installed. In this exemplary embodiment the window105is a standard hung type window. The air conditioner as described herein can also be installed in other type of windows such as a sliding window or some other openable window. To enable a compact installation of the outdoor unit102, the outdoor unit can be provided with a fan arrangement that moves air from the top/bottom of the outdoor unit and out via a front air outlet. This makes it possible to install the outdoor unit closer to the outside wall where the outdoor unit is located. Other advantages can also be obtained as is set forth herein.

InFIG.2, an air-conditioner100with an outdoor unit comprising a packaged refrigeration system is described. However, it is to be understood that an outdoor unit not having a packaged refrigeration system also can use the working principles of the fan configuration and other features as set out herein. For example, a conventional split air-conditioner could be provided with an outdoor unit using the technology as described herein. Thus, it is to be understood that the embodiment ofFIG.2is for illustrational purposes to illustrate an installation where the invention can be used.

InFIG.2, an exemplary implementation of the split type air-conditioner100ofFIG.1is shown in more detail.FIG.2shows the indoor unit101, and the outdoor unit102. The indoor unit comprises an air-to-liquid heat exchanger203. The air-to-liquid heat exchanger203cools (or heats) the air flowing in the indoor unit101. Further, a liquid to refrigerant heat exchanger, in particular a compact liquid-to-refrigerant heat exchanger204is provided in the outdoor unit102. The compact liquid-to-refrigerant heat exchanger204works as an evaporator. Further a main pump205is provided to circulate a liquid solution used as an energy transport media from the indoor unit101to the outdoor unit102(and back again). The main pump can equally be located in the outdoor unit102. The liquid solution is circulated via the connection system103. In this example the connection system103is formed by two connection pipes206and207. Since, the connection system103can be made to work at relatively low pressure (around 1 bar), the pipes206and207can alternatively be hoses or similar devices that are easy to handle and can be provided with connectors that can withstand a low pressure. The outdoor unit102further comprises a refrigeration system, comprising a compressor216driving a refrigerant via that an air-cooled heat exchanger215via an expansion valve220and the compact liquid-to-refrigerant heat exchanger204back to the compressor216. The refrigeration system of the outdoor unit can be factory installed such that the user or installer does not have to work with the circuit circulating the refrigerant. The refrigerant circulated via the air-cooled heat exchanger215can then be filled in the factory. There will then be no need to handle a refrigerant during installation, because the refrigerant circuit of the outdoor unit102is factory sealed.

Further, a liquid tank208can be located on the top of the system. The liquid tank208can be connected to the circuit circulating the energy transport media. In accordance with one example the liquid tank can be connected to the suction port of the main pump205. The tank208can include a level sensor209for controlling the amount of liquid solution circulated between the indoor unit101and the outdoor unit102needed for proper operation of the system100. A box210can be provided under the indoor heat exchanger203for collecting any condensate that is generated on the indoor heat exchanger203. A sensor211can be provided to detect the water level inside of the condensate box210. The sensor211can generate a signal that can be used to control a condensate water pump212. When activated the water pump212is adapted to pump water from the box210to outside of the indoor unit101. In particular water can be pumped outside of the building where the indoor unit is mounted to be released on the outside. Hereby an arrangement that can pump condensate water from the indoor unit101to the outside is obtained.

In accordance with some embodiments the water is pumped to the outside unit102. The pumped water can then for example be pumped through a drainage line213towards a spray device214located on the top of the outdoor air-cooled heat exchanger215, which is connected to the compressor216.

FIG.2further depicts a fan221provided in the indoor unit101for circulating air in the indoor unit. Also, a fan222is provided in the outdoor unit for circulating air in the outdoor unit102. The connection system103can further be provided with a connection device218. The connection device218can for example be a quick connection to in a quick and safe manner interconnect the piping of the indoor unit101with the piping of the outdoor unit102. The connection device can advantageously be located on the top part of the outdoor unit. By connecting the indoor unit101with the outdoor unit102, an energy transport media can be circulated between the indoor unit101and the outdoor unit102. Also, condensate water can be transported from the indoor unit to the outdoor unit102via the connection system103.

In use, the air conditioner100decreases the temperature of the energy transport media using the external packaged AC device of the outdoor unit102. The cooling effect is produced in the compact heat exchanger204located in the refrigeration system of the outdoor-unit102, allowing in turn a temperature drop of the energy transport media, which is then transported in to the indoor unit101via the connection system103. Then, the energy transport media at lower temperature absorbs the thermal energy from the space to be conditioned, by using the low-pressure air-to-liquid heat exchanger203of the indoor unit101. Heat is then returned from the inside unit101to the outside unit102by returning the energy transport media to the outside unit when having being heated in the indoor unit101that is installed in the indoor space to be conditioned.

Because the cooling capacity production is isolated to the refrigeration circuit located in the outdoor unit102all heavy and noisy components can be confined to the outside unit and the indoor environment can be close to free of noise. Also, there is very little space required for the indoor unit. Because the connection system103used to transfer heat between the indoor unit101system can be a low-pressure system it can use an energy transport media that is easy to handle, such as water a water based solution, or some other liquid media such as ethanol.

Thus, in accordance with some embodiments, an aqueous media can be used to transport the energy from the indoor space to be conditioned to the compact evaporator located in the external packaged device. The main pump205will ensure the flow of the energy transport media by pumping the aqueous media, and the external cooling unit will reject the heat generated in the process to the ambient outdoor air.

This is made possible since the external, packaged cooling system located in the outdoor unit can comprise all the standard constitutive elements in a refrigeration system, such as compressor, condenser, expansion device, evaporator and control system, and refrigerant.

InFIG.3, an exemplary outdoor unit102of a type similar to the embodiment ofFIG.2is shown.FIG.3shows a sectional view from the side to the right and a sectional top view to the right. The outdoor unit102has a structure265wherein the components of the outdoor unit are located. The structure265can generally have a top section, a bottom section and a casing for protecting the components inside the structure of the outdoor unit. InFIG.3, a compressor216is provided. In this exemplary embodiment, the compressor drives a refrigerant via an air-cooled heat exchanger215via an expansion valve220and a compact refrigerant-to-liquid heat exchanger204back to the compressor216. Further, a fan230is provided. In the embodiment the fan230is implemented by two axial fans. Other types of fans could also be used such as a radial fan. The outdoor unit102can be connected to an indoor unit via the connectors240. An electronic and control box250can be provided to implement the control mechanism of the outdoor unit102. Also, a free space260for air circulation is indicated inFIG.3. The fan230is arranged to move air in the outdoor unit such that air does not have to pass through the back-side of the outdoor unit when the outdoor unit is mounted close to a wall. Hereby it is made possible to mount the outdoor unit very close to or even directly on a wall, since no air has to pass the back-side of the outdoor unit102. This can make installation easier and also there is less space required for installing the outdoor unit. An additional advantage can be that the load on the arrangement used for securing the outdoor unit can be reduced.

As is seen inFIG.3in the left view, the compressor216can be located at the back-side of the outdoor-unit102, i.e. the side facing the wall when the outdoor unit is mounted at a wall. The compressor216can also be placed centrally in a sideway direction. Thus, in accordance with one embodiment the compressor is located centrally at the backside of the outdoor unit when the outdoor unit is mounted on a wall.

Further, in accordance with some embodiments, a compact refrigerant—to liquid heat exchanger204can be located at the backside of the outdoor-unit. Also, the electronic and control box250can be located at the back-side. This makes it possible to locate an air-to-refrigerant heat exchanger215and a fan230in the remaining space of the outdoor unit allowing air to pass through the air-to-refrigerant heat exchanger215. Air can be blown through the air-to-refrigerant heat exchanger215by the fan230from the top-section and/or the bottom section of the outdoor unit102. The air-to-refrigerant heat exchanger215can thus be placed in the interior part the casing, just in front of the rest of components, with a separation between them that creates a free channel where the air can cross the air-to-refrigerant heat exchanger215and flow with a low restriction. In accordance with some embodiments, the fan230that drive the air flow can be placed on the top of the outdoor unit102.

Since the compressor216is normally the heaviest component of the system, a location thereof at the center-back of the structure, ensures a balanced system with respect to the width of the unit. In a conventional air-conditioner it is often the case that the outdoor unit has a heavier side, which corresponds to the side where the compressor is located. This makes it difficult to transport and install a conventional outdoor unit.

Furthermore, the location of many of the heavy components as exemplified above at the back side of the outdoor unit will provide an outdoor unit102with a center of gravity located in the low center-back of the outdoor unit102. This will provide an equilibrated and steady structure for the outdoor unit102.

FIG.4ashows the layout of a standard outdoor unit.FIG.4bshows the layout of an outdoor unit in accordance with the teachings herein. InFIG.4a, a standard outdoor split AC unit400is shown.FIG.4afurther shows the structure402needed to support the outdoor unit400. The structure402is mounted on a wall300. The outdoor unit400has a backside air intake404facing the wall surface. The outdoor unit400further has an air exhaust406located on the front side of the outdoor unit400. InFIG.4ban outdoor unit102having a fan arrangement in accordance with the teachings herein is shown. InFIG.4b, a structure270that supports the outdoor unit102is provided. The structure270is mounted on a wall300. The outdoor unit102has a top side air intake275. The outdoor unit102further has an air outlet277intake located on the front side of the outdoor unit102.

In a configuration as depicted inFIG.4a, a minimum distance between the wall and the air intake area of the outdoor unit400is required to ensure its proper operation. A typical minimum distance to the wall300is between 15 cm to 30 cm. On the other hand, the layout of the outdoor unit102described herein, does not need any separation between the outdoor unit102and the wall300. As a result of that, the weight supported by the structure270(W2) and the resulting momentum (M2) is much smaller compared to the corresponding values for the structure402of a conventional outdoor unit400having to cope with a higher weight (W1) and a higher Momentum (M1).

The air flow path can be configured in accordance with some different alternatives. InFIGS.5a-5d, different embodiments that can be used for different configurations are depicted.

In accordance with the embodiment ofFIG.5a, a design where the fan push air and where the fan is located at the top section of the outdoor unit102is shown. In such a configuration as is shown inFIG.5athe air inlet291is located at the top of the outdoor unit102and air is pushed through the heat exchanger215to the air exit the outdoor unit in an outlet293in the front of the outdoor unit102. The fan230can also be driven in the reverse direction. The fan230will then suck air via the heat exchanger215to be blown out at the top section of the outdoor unit102. Such a configuration is shown inFIG.5b.

In some embodiments, air can enter/exit the outdoor unit102via the bottom section of the outdoor unit. InFIG.5ca design where the components inside the outdoor unit are placed on a base formed by a grill280that allows air to enter from under the outdoor unit. The fan230is then located at the bottom section of the outdoor unit102to push air from an inlet292in the bottom section via the heat exchanger215out through an outlet293in the front of the outdoor unit102. The fan at the bottom of the outdoor unit102shown inFIG.5ccan also be run in the opposite direction to draw air from the front section of the outdoor unit102via the heat exchanger215out through the bottom of the outdoor unit102. Such a configuration is shown inFIG.5d. When the outdoor unit is open in the bottom section, the top section can be closed.

In accordance with some embodiments two fans230can be used to provide the air flow in the outdoor unit102. By using two fans, the air flow needed in the heat rejection process can be ensured with a more homogeneous air distribution over the whole heat transfer area of the condenser(s), allowing in turn the use a smaller condenser, due to an improved heat transfer process. In accordance with one embodiment, two fans are mounted on the top of the outdoor unit when mounted on a wall. In an alternative embodiment two fans are mounted at the bottom of the outdoor unit when mounted on a wall. In yet an alternative embodiment fans230are located at both the top and the bottom and air enters/exits the outdoor unit102both at the top section and the bottom section. In other words, air can be draw via heat the exchanger215to exit both at the top and the bottom section or pushed in the opposite direction. In such embodiments fans230can be provided both at the top section and the bottom section of the outdoor unit.

The outdoor unit as described herein can be made very compact and have relatively low weight. For example, the height can be 400 to 600 mm, the width can be 500 to 650 mm and the depth can be 280 to 330 mm. Further the weight can be less than 30 kg.