Indoor unit of air conditioner

Abstract

 An indoor unit of an air conditioner, includes a blower fan disposed within a casing; and a heat exchanger for heat-exchanging between refrigerant and air flowing by the blower fan, said heat exchanger connected to a refrigerant inlet pipe for introducing refrigerant and a refrigerant outlet pipe for discharging a refrigerant, wherein the refrigerant inlet pipe is connected to a side of the heat exchanger, where a flow velocity of the air passing through the heat exchanger is relatively high. Accordingly, efficiency of heat exchange between the indoor air and refrigerant can be improved, and thus cooling and heating efficiency of the indoor air is improved, thereby improving performance of the air conditioner. Also, by reducing the operation time of the air conditioner, power consumption can be reduced.

Description

[0001] The present invention relates to an indoor unit of an air conditioner, and particularly, to an indoor unit of an air conditioner capable of improving efficiency of heat exchange between refrigerant and air.

[0002] In general, an air conditioner is an apparatus for maintaining a pleasant room temperature by using latent heat of vaporization of refrigerant, which is circulated in a refrigerating cycle of a compressor, a heat exchanger, an expansion valve and an evaporator.

[0003] The air conditioner performs cooling operation on a room through a series of processes that refrigerant is compressed by the compressor at up to saturation pressure, the compressed refrigerant is liquefied by the heat exchanger, the liquefied refrigerant is introduced to the evaporator in a state of being decompressed and expanded by throttling of the expansion valve, and the introduced refrigerant is heat-exchanged with ambient air of the evaporator to be evaporated in the evaporator.

[0004] Such an air conditioner is divided into an integral type air conditioner and a split type air conditioner according to whether an indoor unit and an outdoor unit are coupled together, and the split type air conditioner is divided into a wall mounted type and a floor standing type according to its installation type.

[0005] As shown in FIGS. 1 and 2, the indoor unit of the conventional air conditioner includes a casing 110 having an air suction part 112 for sucking the air and an air discharge part 114 positioned at an upper portion, for discharging the air; a blower fan 120 installed inside the casing 110, for sucking and discharging the air; and a indoor heat exchanger 130 installed inside the casing 110, for heat-exchanging the air flowing inside the casing 110 with a refrigerant.

[0006] The indoor heat exchanger 130 is an A-coil heat exchanger type having a pair of slabs 131 and 132. As for the slabs 131 and 132, a plurality of tubes 133 through which refrigerant flows are respectively installed in the slabs, and the slabs 131 and 132 are at a predetermined angle as their upper ends of the slabs are coupled together and their lower ends are apart from each other.

[0007] A refrigerant inlet 136 connected to a refrigerant inlet pipe 134 for introducing refrigerant from an outdoor unit (not shown), thus to introduce the refrigerant to the tubes 133 of the slabs 131 and 132 is installed at a lower end of each slab 131 and 132. And a refrigerant outlet 137 connected to a refrigerant outlet pipe 135 for discharging refrigerant to an outdoor unit, thus to discharge the refrigerant having passed through the tubes 133 toward the outdoor unit is installed at an upper end of each slab 131 and 132.

[0008] In addition, a thermostatic expansion valve (TXV) 138 for controlling a flow of refrigerant according to a temperature of a refrigerant and a refrigerant distributor 139 for distributing refrigerant toward each refrigerant inlet 136 are installed at the refrigerant inlet pipe 134.

[0009] Meanwhile, the blower fan 120 is disposed under the indoor heat exchanger 130, and an outlet of the blower fan 120 is arranged toward an upper side of the indoor heat exchanger 130.

[0010] By such a structure, the refrigerant repetitively undergoes a series of processes that refrigerant compressed by the compressor emits heat to ambient air while passing through an outdoor heat exchanger, to thereby be changed into a high temperature and high pressure liquefied refrigerant, the high temperature and high pressure liquefied refrigerant is decompressed and expanded by being introduced to the TXV 138 through the refrigerant inlet pipe 134, the refrigerant having passed through the TXV 138 is introduced to the indoor heat exchanger 130 through the refrigerant inlet 136, is evaporated by absorbing ambient heat, to thereby be a low temperature and low pressure gaseous refrigerant, and then is sucked again to the compressor through the refrigerant outlet 137 and the refrigerant outlet pipe 135.

[0011] At this time, the blower fan 120 is driven theretogether. According to this, the indoor air is introduced into the casing 110 through the air suction part 112, is heat-exchanged by coming in contact with the indoor heat exchanger 130, and is discharged to the outside of the casing 110 through the air discharge part 114.

[0012] And, in heating operation, refrigerant moves in reverse order of the freezing cycle, and the indoor heat exchanger 130 functions as a condenser, so that a room is heated.

[0013] Meanwhile, because the blower fan 120 is disposed under the indoor heat exchanger 130, air sent from the blower fan 120 flows from the lower ends of the slabs 131 and 132 toward the upper ends. Here, a passage of the air flowing from the blower fan 120 becomes narrower from a lower side toward an upper side because a distance between the slabs 131 and 132 gets longer from their upper ends toward the lower ends. Accordingly, a flow velocity of air flowing from the blower fan 120 is higher at the upper end sides of the slabs 131 and 132 rather than at their lower end sides of the slabs 131 and 132.

[0014] However, in the indoor unit of the conventional air conditioner having such a structure, refrigerant passing through the upper ends of the slabs 131 and 132 has undesirably already overheated to some degree by heat-exchange with the air because the refrigerant is introduced to the refrigerant inlets 136 of the lower ends of the slabs 131 and 132, passes through the tubes 133, and is discharged to the refrigerant outlets 137 of the upper ends of the slabs 131 and 132. Accordingly, even though a flow velocity of the air passing the upper end of the slab 131 and 132 is higher than that of the air passing the lower end of the slab 131 and 132, heat exchange between air and refrigerant cannot be effectively performed at the upper ends of the slabs 131 and 132.

[0015] Therefore, an aim of the present invention is to provide an air conditioner capable of improving efficiency of heat exchange between a refrigerant and air and improving cooling and heating efficiency by installing a refrigerant inlet for introducing refrigerant to an indoor exchanger at a position where a flow velocity of air is higher than a position of a refrigerant outlet.

[0016] To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided an indoor unit of an air conditioner, comprising a blower fan disposed within a casing; and a heat exchanger for heat-exchanging between refrigerant and air flowing by the blower fan , said heat exchanger connected to a refrigerant inlet pipe for introducing refrigerant and a refrigerant outlet pipe for discharging refrigerant, wherein the refrigerant inlet pipe is connected to a side of the heat exchanger, where a flow velocity of the air passing through the heat exchanger is relatively high.

[0017] The foregoing and other aims, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a unit of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

[0019] In the drawings:

FIG. 1 is an exploded perspective view showing an indoor unit of a conventional air conditioner;

FIG. 2 is a schematic view showing an indoor unit of the conventional air conditioner;

FIG. 3 is an exploded perspective view showing an indoor unit of an air conditioner in accordance with the present invention; and

FIGS. 4 and 5 are schematic views showing an indoor unit of the air conditioner in accordance with the present invention.

[0020] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

[0021] As shown in FIGS. 3 and 4, an outdoor unit of an air conditioner in accordance with the present invention includes a casing 10 having an air suction part 12 positioned at a front side of the casing 10 and an air discharge part 14 positioned at an upper side of the casing 10; a blower fan 20 installed within the casing 10, for sucking and discharging air; and an indoor heat exchanger 30 installed inside the casing 10 and heat-exchanging between refrigerant and air flowing by the blower fan 20 and passing through the indoor heat exchanger 30.

[0022] The indoor heat exchanger 30 is an A-coil heat exchanger type having a pair of slabs 31 and 32. As for the slabs 31 and 32, a plurality of tubes 33 respectively connected to an outdoor unit, a refrigerant inlet pipe 32 and a refrigerant outlet pipe 35 thus to flow a refrigerant therethrough are respectively installed therein, and the slabs 31 and 32 are arranged to be at a predetermined angle as upper ends of the slabs 31 and 32 are coupled to each other and their lower ends are apart from each other.

[0023] Here, a flow velocity of the air is higher at the upper ends where the slabs 31 and 32 are coupled together rather than at the lower ends. Therefore, to improve efficiency of heat-exchange between refrigerant passing through the slabs 31 and 32 and air, a refrigerant inlet 36 connected to the refrigerant inlet pipe 34 is installed at each upper end of the slabs 31 and 32, and a refrigerant outlet 37 connected to the refrigerant outlet pipe 35 is installed at each lower end of the slabs 31 and 32.

[0024] Also, a thermostatic expansion valve (TXV) 38 for controlling a flow of a refrigerant according to a temperature of refrigerant; and a refrigerant distributor 39 for distributing refrigerant toward each refrigerant inlet 36 are installed at the refrigerant inlet pipe 34.

[0025] Meanwhile, the blower fan 20 is disposed adjacent to a lower side of the indoor heat exchange 30 in comparison with its adjacency to an upper side of the indoor heat exchanger 30, and an outlet of the blower fan 20 is installed toward the upper side of the indoor heat exchanger 30. Such a blower fan 20 is formed by coupling a turbo fan, a kind of a centrifugal fan, to a fan motor (not shown) so as to suck, pressurize and discharge the indoor air.

[0026] The refrigerant distributor 39 equally distributes refrigerant to each refrigerant inlet 36, and pipes coupled to the refrigerant distributor 39 preferably have a vertical length of at least about 5cm or longer.

[0027] Meanwhile, as shown in FIG. 5, preferably, a four way valve connected to the refrigerant inlet pipe 34 and the refrigerant outlet pipe 35, for converting circulation of refrigerant discharged from the compressor according to a heating cycle or a cooling cycle is installed, so that the indoor unit in accordance with the present invention can carry out not only the cooling operation but also the heating operation.

[0028] By such a structure, the refrigerant repetitively undergoes a series of processes that refrigerant compressed by driving of the compressor emits heat to ambient air while passing through an outdoor heat exchanger, to thereby be changed into a high temperature high pressure liquefied refrigerant, the high temperature and high pressure liquefied refrigerant is decompressed and expanded by being introduced to the TXV 38 through the refrigerant inlet pipe 34, the refrigerant having passed through the TXV 38 is introduced to the indoor heat exchanger 30 through the refrigerant inlet 36, is evaporated by absorbing ambient heat, to thereby be a low temperature and lower pressure gaseous refrigerant, and then is sucked again to the compressor through the refrigerant outlet 37 and the refrigerant outlet pipe 35.

[0029] At this time, the blower fan 20 is driven theretogether. According to this, the indoor air is introduced into the casing 10 through the air suction part 12, is heat-exchanged by coming in contact with the indoor heat exchanger 30, and is discharged to the outside of the casing 10 through the air discharge part 14.

[0030] And, in heating operation, refrigerant moves in reverse order of the freezing cycle, and the indoor heat exchanger 30 functions as a condenser, so that a room can be heated.

[0031] Meanwhile, because the blower fan 20 is disposed under the indoor heat exchanger 30, the air sent from the blower fan 20 moves from the lower ends of the slabs 31 and 32 toward their upper ends. Here, a distance between the slabs 31 and 32 gets longer from their upper ends toward the lower ends. Therefore, a passage of the air flowing from the blower fan 20 gets narrower from a lower side toward an upper side. Accordingly, a flow velocity of the air flowing from the blower fan 20 is higher at the upper ends of the slabs 31 and 32 rather than at the lower ends.

[0032] At this time, because the refrigerant inlet pipe 34 is connected to the upper end of the slab 31 and 32, the refrigerant is introduced to the upper end of the slab 31 and 32, where a flow velocity of the air is high, and is heat-exchanged with the air while flowing along the tube 33. And because the refrigerant outlet pipe 35 is connected to the lower end of the slab 31 and 32, the refrigerant heat-exchanged while passing through the tube 33 is discharged from the lower end of the slab 31 and 32, where a flow velocity of the air is low. Accordingly, efficiency of heat exchange between the refrigerant and the air can be remarkably improved at a portion where the flow velocity of the air is high.

[0033] In the indoor unit of the air conditioner in accordance with the present invention, a refrigerant inlet pipe and a refrigerant outlet pipe are respectively connected to an indoor heat exchanger, so that refrigerant is introduced to a portion where a flow velocity of the air passing the indoor heat exchanger is high and is discharged to a portion where a flow velocity of the air is low. Accordingly, efficiency of the heat exchange between the indoor air and the refrigerant can be improved, and performance of the air conditioner can be improved by improving heating and cooling effect for the air. Also, by reducing the operation time of the air conditioner, power consumption can be reduced.

[0034] The present invention intends to improve efficiency of heat exchange between refrigerant and air by introducing the refrigerant to a portion where a flow velocity of the air passing a heat exchanger is high and discharging the refrigerant from a portion where the flow velocity of the air is low. Therefore, it should also be understood that the above-described embodiments are not limited by an indoor unit having an A coil type heat exchanger of the foregoing description, but rather can be applied to every indoor unit having a heat exchanger in which a flow velocity of the air is different depending on a portion of the heat exchanger.

Claims

1. An indoor unit of an air conditioner, comprising:

a blower fan disposed within a casing; and

a heat exchanger for heat-exchanging between refrigerant and air flowing by the blower fan, said heat exchanger connected to a refrigerant inlet pipe for introducing refrigerant and a refrigerant outlet pipe for discharging refrigerant,

wherein the refrigerant inlet pipe is connected to a side of the heat exchanger, where a flow velocity of the air passing through the heat exchanger is relatively high.

2. The indoor unit of claim 1, wherein the heat exchanger includes a pair of slabs having therein a tube through which refrigerant passes and disposed to be at a predetermined angle therebetween as ends of the slabs are connected to each other.

3. The indoor unit of claim 2, wherein the refrigerant inlet pipe is connected to each first end of the slabs, where the slabs are connected to each other.

4. The indoor unit of claim 3, wherein the refrigerant outlet pipe is connected to each second end of the slabs, said second end opposite to the first end of the slab.

5. The indoor unit of claim 1, wherein the heat exchanger is an A-coil heat exchanger type having a pair of slabs disposed to be at a predetermined angle as upper ends of the slabs are connected to each other and lower ends of the slabs are apart from each other.

6. The indoor unit of claim 5, wherein the refrigerant inlet pipe is connected to each upper end of the slabs.

7. The indoor unit of claim 5, wherein the refrigerant outlet pipe is connected to each lower end of the slabs.

8. The indoor unit of claim 5, wherein the blower fan is disposed under the heat exchanger.

9. The indoor unit of claim 1, wherein a four way valve connected to the refrigerant inlet pipe and the refrigerant outlet pipe, for circulating refrigerant according to a heating cycle and a cooling cycle is installed.

10. The indoor unit of claim 9, wherein a thermostatic expansion valve (TXV) for controlling a flow of refrigerant according to a temperature of a refrigerant is installed at the refrigerant inlet pipe.

Drawing