JP7685449B2 - Air conditioners - Google Patents

Description

The present invention relates to an air conditioner that can perform a cleaning operation to clean the indoor heat exchanger inside the indoor unit.

Conventionally, there have been air conditioners of this type that perform a cleaning operation in which condensation water is generated on the surface of the indoor heat exchanger by performing a cleaning cooling operation in which the indoor heat exchanger in the indoor unit installed indoors functions as an evaporator, and the condensation water is used to wash away dust adhering to the surface of the indoor heat exchanger. (For example, Patent Document 1)

JP 2009-300030 A

However, if the amount of condensation water generated on the surface of the indoor heat exchanger during cleaning cooling operation is small, the amount of condensation water dripping from the indoor heat exchanger into the drain pan will also be small, and after the cleaning operation is completed, dust contained in the condensation water that drips into the drain pan during cleaning cooling operation will not be discharged from the drain pan along with the condensation water and will remain there, raising the risk of the drain pan becoming dirty, so there is room for improvement.

In order to solve the above-mentioned problems, the air conditioner according to the present invention includes an indoor unit, an indoor heat exchanger installed in the indoor unit and through which a refrigerant flows,
An indoor fan installed in the indoor unit for blowing air to the indoor heat exchanger;
A drain pan that collects condensation water dripping from the indoor heat exchanger and discharges it to the outside;
a cleaning cooling operation in which the indoor fan is driven and a low-temperature refrigerant is caused to flow through the indoor heat exchanger to condense and clean the indoor heat exchanger;
A control unit that controls the cleaning cooling operation,
A water retention section that is configured within an area surrounded by a rib extending in the longitudinal direction of the drain pan, a convex portion that faces the longitudinal end of the rib and extends in a direction perpendicular to the rib, and a wall portion that faces the longitudinal direction of the rib and extends in a direction parallel to the rib, and that temporarily stores condensation water dripping from the indoor heat exchanger;
a drain portion configured by a gap formed between the rib and the protruding portion, for draining the condensation water stored in the water retaining portion to the drain pan outside the water retaining portion;
The present invention is characterized in that the capacity of the discharge section to discharge condensation water is set to be less than the amount of condensation water generated on the indoor heat exchanger during the cleaning cooling operation.

In a second aspect of the present invention, the protrusion has a recess that is lower in height than the rib, and the recess constitutes the discharge portion.

In a third aspect of the present invention, a heat insulating material is provided in the drain pan, and the water retaining portion and the discharge portion are formed in the heat insulating material.

According to this invention, the discharge capacity of the discharge section that discharges condensation water temporarily stored in the drain pan is less than the amount of condensation water generated by the cleaning cooling operation. Therefore, even if the amount of condensation water generated in the indoor heat exchanger and dripping into the drain pan during cleaning cooling operation is small, the condensation water that drips into the drain pan is temporarily stored, causing dust to float and allowing it to be discharged from the drain pan together with the condensation water, thereby preventing the drain pan from becoming dirty with dust.

1 is a schematic diagram of an air conditioner according to one embodiment of the present invention; FIG. 2 is a cross-sectional side view of the indoor unit of the embodiment. FIG. 2 is a control block diagram of the embodiment. FIG. 2 is a perspective view illustrating the drain pan structure of the embodiment. FIG. 2 is a partially enlarged plan view illustrating the drain pan structure of the embodiment. FIG. 11 is a partially enlarged perspective view illustrating a drain pan structure according to another embodiment.

One embodiment of the present invention is described below with reference to the attached drawings.

Figure 1 shows an air conditioner 10 (air conditioner) equipped with a refrigerant circuit 11 through which a refrigerant flows. The air conditioner 10 has the function of performing cooling operation to cool the room R, and heating operation to warm the room R. The refrigerant circuit 11 includes an outdoor unit 20 arranged outside Ou, and an indoor unit 30 arranged inside the room R. Unless otherwise specified below, the direction in which the refrigerant circulates is based on cooling operation.

The outdoor unit 20 has a switching valve 21 that switches the refrigerant flow direction during cooling operation and heating operation, a compressor 22 that compresses the refrigerant that has passed through the switching valve 21, an outdoor heat exchanger 23 through which the refrigerant that has been compressed in the compressor 22 and has become high temperature and high pressure flows, a propeller fan 24 that sends outdoor air toward the outdoor heat exchanger 23, and an expansion valve 25 that reduces the pressure of the refrigerant that has passed through the outdoor heat exchanger 23.

The indoor unit 30 is hung on a wall Wa in the room R. The indoor unit 30 has an indoor fan 31 that takes in air from the room and blows air into the room, an indoor heat exchanger 32 that exchanges heat with the indoor air taken in by the indoor fan 31, and a case 33 that houses the indoor fan 31 and the indoor heat exchanger 32.

Refer to Figure 2. The indoor heat exchanger 32 is composed of a front indoor heat exchanger 32a located on the front side of the case 33, and a rear indoor heat exchanger 32b located on the rear side of the case 33. The front indoor heat exchanger 32a is divided into two parts in the vertical direction.

The case 33 has an air outlet 33a, which is the outlet for the air blown out by the indoor fan 31. The air outlet 33a is provided with left-right louvers 34 that adjust the left-right direction of the blown air, and up-down louvers 35 that adjust the up-down direction of the blown air.

Inside the case 33, a drain pan 36 is installed below the front indoor heat exchanger 32a. The drain pan 36 is a container-like structure surrounded by a wall portion 36a extending in the vertical direction and has an open top. Insulation material 37 is installed on the bottom surface of the drain pan 36, and condensation water generated in the front indoor heat exchanger 32a drips onto the insulation material 37. Since the drain pan 36 is longer than the left-right width of the front indoor heat exchanger 32a, it is possible to collect all of the condensation water generated and dripping from the front indoor heat exchanger 32a without leakage. The detailed structure of the insulation material 37 will be described later.

The cooling operation will be explained. The refrigerant that has been made high temperature and high pressure by the compressor 22 exchanges heat with the outdoor air in the outdoor heat exchanger 23, releasing heat. At this time, the propeller fan 24 rotates, forcing the outdoor air to flow around the periphery of the outdoor heat exchanger 23, promoting the heat exchange. The refrigerant that has passed through the outdoor heat exchanger 23 and released heat is reduced in pressure in the expansion valve 25, and its temperature drops. The refrigerant with the lowered temperature flows to the indoor heat exchanger 32.

The low-temperature refrigerant that flows into the indoor heat exchanger 32 exchanges heat with the indoor air in the room R in the indoor heat exchanger 32, cooling the air in the room R. The cooled air is blown into the room R by the indoor fan 31. The indoor fan 31 forces the air to flow around the periphery of the indoor heat exchanger 32, promoting heat exchange with the refrigerant.

During heating operation, the switching valve 21 switches the refrigerant flow path, circulating the refrigerant in the opposite direction to that during cooling operation.

Figure 3 shows a control block diagram of the air conditioner device 10 (see Figure 1). The indoor unit 30 incorporates an indoor control unit 40 (control unit) that controls the indoor fan 31, the left and right louvers 34, and the up and down louvers 35, a temperature sensor 41 that detects the indoor temperature, an indicator lamp 42 that displays the operating status via the indoor control unit 40, and a remote control transmitting/receiving unit 43 that exchanges predetermined information with the remote control 12.

The indoor control unit 40 has a memory unit 44 that stores data received via the remote control transmission/reception unit 43, the detection value of the temperature sensor 41, the set temperature and reference time described below, and other specified programs, and multiple timers t1 to t4 that measure elapsed time.

The outdoor unit 20 has an outdoor control unit 45 that is electrically connected to the indoor control unit 40. The indoor control unit 40 can control the switching valve 21, the compressor 22, the propeller fan 24, and the expansion valve 25 via the outdoor control unit 45.

The air conditioner unit 10 also has a function of performing a cleaning operation to clean dust adhering to the surface of the indoor heat exchanger 32 (see FIG. 1). The control details of the cleaning operation of the air conditioner unit 10 are explained below.

When a user operates a specific switch on the remote control 12 to instruct the start of cleaning operation, the indoor control unit 40, when it determines that the room temperature detected by the temperature sensor 41 is at or above a temperature at which cleaning operation can be performed, switches the switching valve 21 so that refrigerant flows through the refrigerant circuit 11 in the same way as in cooling operation, and then starts cleaning cooling operation, which drives the compressor 22 at a specific rotation speed and drives the indoor fan 31 at a specific rotation speed. By performing cleaning cooling operation, low-temperature refrigerant flows through the indoor heat exchanger 32, and the surface of the indoor heat exchanger 32 becomes below the dew point temperature. Condensation water is generated and drips on the surface of the indoor heat exchanger 32, and the dust attached to the surface of the indoor heat exchanger 32 can be washed away by the condensed water.

After performing the cleaning cooling operation, if the indoor control unit 40 determines that a predetermined time has elapsed, it stops driving the compressor 22 and performs a blowing operation in which only the indoor fan 31 is driven for a predetermined time, and then performs the cleaning cooling operation again. If the cleaning cooling operation is performed for a long period of time, moisture will accumulate around the indoor heat exchanger 32, making it difficult to efficiently generate condensation water on the surface of the indoor heat exchanger 32. By blowing the moisture around the indoor heat exchanger 32 into the room with the blowing operation, it is possible to continue to efficiently generate condensation water on the surface of the indoor heat exchanger 32 during the cleaning cooling operation, and the cleaning effect of the indoor heat exchanger 32 can be improved.

During the operation of repeating the cleaning cooling operation and the air blowing operation at predetermined intervals, if the indoor control unit 40 determines that the room temperature detected by the temperature sensor 41 has fallen below a predetermined temperature, it stops the cleaning cooling operation or the air blowing operation, switches the switching valve 21 so that the refrigerant flows through the refrigerant circuit 11 as in the heating operation, and then starts the cleaning heating operation in which the compressor 22 is driven at a predetermined rotation speed and the indoor fan 31 is driven at a predetermined rotation speed. If the cleaning cooling operation is continued, the temperature of the indoor heat exchanger 32 continues to drop, and the condensed water generated on the surface of the indoor heat exchanger 32 freezes, making it impossible to clean the indoor heat exchanger 32 with the condensed water. By performing the cleaning heating operation, the surface temperature of the indoor heat exchanger 32 can be increased, preventing the condensed water generated on the surface of the indoor heat exchanger 32 from freezing, and making it possible to continue cleaning the indoor heat exchanger 32 with the condensed water.

After performing the cleaning heating operation, if the indoor control unit 40 determines that the room temperature detected by the temperature sensor 41 has reached a predetermined temperature or higher, it stops the cleaning heating operation and performs the cleaning cooling operation again. By repeating the cleaning cooling operation and the cleaning heating operation, condensation water can be continuously and efficiently generated on the surface of the indoor heat exchanger 32.

When the indoor control unit 40 determines that a predetermined time has elapsed since the remote control 12 instructed to start the cleaning operation, it stops the cleaning cooling operation, air blowing operation, or cleaning heating operation that is being performed at the time the predetermined time has elapsed, and performs a cleaning drying operation in which only the indoor fan 31 is driven at a predetermined rotation speed. The surface of the indoor heat exchanger 32 becomes wet with condensed water due to the cleaning cooling operation, and if the indoor heat exchanger 32 is left in a wet state, there is a risk of mold growing on the surface of the indoor heat exchanger 32. By performing the cleaning drying operation, the indoor heat exchanger 32 can be dried, thereby preventing mold from growing on the surface of the indoor heat exchanger 32.

When the indoor control unit 40 determines that the cleaning drying operation has been performed for a predetermined period of time, it stops the indoor fan 31 and ends the cleaning operation.

Next, the detailed structure of the drain pan 36 in this embodiment will be described with reference to Figures 4 and 5.

The drain pan 36 is formed with walls 36a erected to surround the bottom surface in the front-rear and left-right directions, drain guides 36b located at the left and right ends, through which condensation water discharged from the insulation material 37 flows, and drain ports 36c that discharge the condensation water flowing through the drain guides 36b to the outside. By attaching one end of a drain hose (not shown) to either one of the drain ports 36c formed at the left and right ends and installing the other end of the drain hose at an appropriate position outside, the condensation water accumulated in the drain pan 36 can be discharged to the outside. In addition, a stopper is attached to the drain port 36c on the other side to which the drain hose is not attached, preventing the condensation water accumulated in the drain pan 36 from leaking out of the drain port 36c on the other side.

The drain pan 36 is provided with a heat insulating material 37 so as to cover most of the bottom surface (here, the entire bottom surface except for the drain guide portion 36b). The heat insulating material 37 is formed with a rib 37a extending in the left-right direction, which is the longitudinal direction, at approximately the center in the front-rear direction, a convex portion 37b which faces the rib 37a at the left-right end and extends in the front-rear direction, which is a direction perpendicular to the rib 37a, and a wall portion 37c which faces the rib 37a in the front-rear direction and extends in the left-right direction, which is a direction parallel to the rib 37a. The wall portion 37c of the heat insulating material 37 abuts against the inside of the wall portion 36a of the drain pan 36 extending in the left-right direction, and is formed so that the vertical height of the wall portion 37c of the heat insulating material 37 is lower than that of the wall portion 36a of the drain pan 36. The rib 37a and the convex portion 37b are formed so that they have the same vertical height.

The rib 37a has support parts 36a1 formed in multiple left-right locations, each of which is higher in the up-down direction than the other parts. The lower end part of the front indoor heat exchanger 32a at a predetermined position is supported and fixed by the support parts 36a1. In addition, the lower end parts of the left-right ends of the front indoor heat exchanger 32a are installed in close proximity to the protrusions 37b. During cooling and heating operations, the generation of air that passes between the left-right lower end parts of the front indoor heat exchanger 32a and the insulation material 37 and does not exchange heat without passing through the front indoor heat exchanger 32a is suppressed. This suppresses a decrease in the operating efficiency of cooling and heating operations.

The heat insulating material 37 has a water retention section 37d surrounded by the rib 37a, the protrusion 37b, and the rear wall section 37c, and a gap 37e between the rib 37a and the protrusion 37b as a drain section. Condensation water generated in the front indoor heat exchanger 32a mainly drips into the water retention section 37d and is temporarily stored there. The condensation water stored in the water retention section 37d is drained out of the water retention section 37d through the gap 37e. The condensation water drained out of the water retention section 37d through the gap 37e is drained out of the room by the drain outlet 36c via the drain guide section 36b.

The size of the gap 37e is preset so that the discharge capacity for discharging the condensed water accumulated in the water retention portion 37d to the outside of the water retention portion 37d is less than the amount of condensed water generated in the front indoor heat exchanger 32a during washing cooling operation (condensed water amount > discharge capacity). The amount of condensed water varies depending on environmental conditions such as room temperature and indoor humidity, but is set to the amount generated under environmental conditions in normal use (e.g., room temperature 27°C, indoor humidity 60%) (e.g., 1 L/h). The condensed water generated in the front indoor heat exchanger 32a during washing cooling operation and dripping onto the water retention portion 37d does not flow out to the drain guide portion 36b relatively easily compared to when the water retention portion 37d is not formed. Therefore, the depth of the condensed water accumulated in the water retention portion 37d becomes larger, and dust contained in the condensed water is easily discharged to the outside of the water retention portion 37d together with the condensed water accumulated in the water retention portion 37d.

As a result, even if the amount of condensation water that forms on the surface of the indoor heat exchanger 32 and drips into the drain pan 36 during cleaning cooling operation is small, dust in the condensation water that drips into the water retention section 37d can be reliably discharged outside the water retention section 37d and prevented from remaining in the insulation material 37. This prevents dust from remaining in the insulation material 37 and causing the drain pan 36 to become dirty after cleaning cooling operation.

Next, another embodiment of the present invention will be described with reference to FIG. 6. Note that, apart from the protrusion 37b, the embodiment is the same as the above embodiment, so the description will be omitted.

The protrusion 37b is formed with a recess 37b1 as a discharge section that is lower in height in the vertical direction than the rib 37a. When a large amount of condensation water drips from the front indoor heat exchanger 32a during the washing cooling operation, the gap 37e alone is insufficient to discharge the condensation water outside the water holding section 37d, and the condensation water accumulated in the water holding section 37d may climb over the rib 37a and be discharged outside the water holding section 37d. If the position of the condensation water that climbs over the rib 37a and is discharged outside the water holding section 37d is far from the drain guide section 36b, the condensation water is not discharged from the insulation material 37, and dust contained in the condensation water may remain in the insulation material 37, causing the drain pan 36 to remain dirty. By forming the recess 37b1 in the protrusion 37b, the condensation water accumulated in the water holding section 37d flows into the drain guide section 36b through the recess 37b1. Condensed water is not discharged outside the water retention section 37d, which is far from the drain guide section 36b, and dust is prevented from remaining in the drain pan 36 after the cleaning cooling operation.

The recess 37b1 formed in the protrusion 37b is not limited to a structure in which the height is uniformly low as in this embodiment. For example, it may be configured to have multiple surfaces whose upper ends have different heights in the front-to-rear direction, making it possible to adjust the amount of condensation water discharged outside the water retention section 37d.

In this embodiment and another embodiment, the drain pan 36 is provided with the insulating material 37, but this is not limited to the above. Instead of providing the insulating material 37 to the drain pan 36, ribs and protrusions may be formed on the bottom surface of the drain pan 36, and gaps may be formed between the left and right ends of the ribs and the protrusions as discharge sections, and recesses may be formed in the protrusions. In this case, the area surrounded by the wall 36a of the drain pan 36, the ribs, and the protrusions becomes the water retention section.

By setting the size of the gap so that the capacity of the gap to drain condensation water is less than the amount of condensation water generated in the front indoor heat exchanger 32a during cleaning cooling operation, the condensation water can be temporarily stored in the water retention section and then drained outside the water retention section, thereby preventing dust from remaining in the drain pan 36 after cleaning cooling operation.

In addition, in this embodiment and other embodiments, the drain pan 36 is installed below the front indoor heat exchanger 32a, but this is not limited to this. As long as the drain pan 36, which is located in a position where it can collect condensation water generated in the indoor heat exchanger 32 during cleaning cooling operation, is formed with what corresponds to the water retention section and discharge section of the present invention, it falls within the scope of the present invention.

Next, the effects of the present invention will be explained.

The drain pan 36 is provided with a water retention section 37d that temporarily stores condensation water dripping from the indoor heat exchanger 32, and a gap 37e that discharges the condensation water stored in the water retention section 37d to the drain pan 36 outside the water retention section 37d, and the discharge capacity of the condensation water through the gap 37e is set to be less than the amount of condensation water generated on the indoor heat exchanger 32 during cleaning cooling operation. The condensation water generated on the indoor heat exchanger 32 during cleaning cooling operation and dripping into the water retention section 37d is temporarily stored and then discharged outside the water retention section 37d. Dust attached to the water retention section 37d during cleaning cooling operation is floated by the stored condensation water, and the condensation water containing the dust is discharged outside the water retention section 37d. Even if the amount of condensation water that occurs in the indoor heat exchanger 32 and drips into the drain pan 36 during cleaning cooling operation is small, dust remains in the drain pan 36 after cleaning cooling operation, and the drain pan 36 can be prevented from becoming dirty.

The water retention section 37d is formed by an area surrounded by a rib 37a extending in the left-right direction, which is the longitudinal direction of the drain pan 36, a protrusion 37b that faces the left-right end of the rib 37a and extends in a direction perpendicular to the rib 37a, and a rear wall 37c that faces the left-right direction, which is the longitudinal direction of the rib 37a, and extends in a direction parallel to the rib 37a, and the discharge section is formed by a gap 37e formed between the rib 37a and the protrusion 37b. The water retention section 37d, which temporarily stores condensation water that is generated and drips during washing cooling operation, and the discharge section that discharges condensation water from the water retention section 37d can be formed in the drain pan 36 with a simple structure.

The protruding portion 37b also has a recessed portion 37b1 that is lower in height than the rib 37a. When a large amount of condensation water is generated in the indoor heat exchanger 32 during the cleaning cooling operation and drips into the drain pan 36, the condensation water may climb over the rib 37a and be discharged outside the water holding portion 37d, and may not be smoothly guided to the drain guide portion 36b, causing dust in the condensation water to remain in the drain pan 36. By having the recessed portion 37b1 that is lower in height than the rib 37a in the protruding portion 37b, when a large amount of condensation water accumulates in the water holding portion 37d, the condensation water is discharged to the drain guide portion 36b through the recessed portion 37b1. The condensation water climbs over the rib 37a and is discharged outside the water holding portion 37d, preventing the generation of condensation water that does not reach the drain guide portion 36b. This prevents dust from remaining in the drain pan 36 and causing the drain pan 36 to become dirty.

In addition, the insulation material 37 is installed in the drain pan 36, and the water retention portion 37d and the gap 37e, which is the discharge portion, are formed in the insulation material 37. Compared to molding directly on the drain pan 36, the water retention portion 37d and the gap 37e can be easily molded, improving work efficiency.

Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims.

10. Air conditioning equipment (air conditioner)
30 Indoor unit 31 Indoor fan 32 Indoor heat exchanger 36 Drain pan 36a Wall portion 37 Heat insulating material 37a Rib 37b Convex portion 37b1 Concave portion (discharge portion)
37c Wall portion 37d Water retention portion 37e Gap (discharge portion)
40 Indoor control unit (control unit)

Claims (3)

An indoor unit; an indoor heat exchanger installed in the indoor unit and through which a refrigerant flows;
An indoor fan installed in the indoor unit for blowing air to the indoor heat exchanger;
A drain pan that collects condensation water dripping from the indoor heat exchanger and discharges it to the outside;
a cleaning cooling operation in which the indoor fan is driven and a low-temperature refrigerant is caused to flow through the indoor heat exchanger to condense and clean the indoor heat exchanger;
A control unit that controls the cleaning cooling operation,
The drain pan includes:
A water retention section that is configured within an area surrounded by a rib extending in the longitudinal direction of the drain pan, a convex portion that faces the longitudinal end of the rib and extends in a direction perpendicular to the rib, and a wall portion that faces the longitudinal direction of the rib and extends in a direction parallel to the rib, and that temporarily stores condensation water dripping from the indoor heat exchanger;
a drain portion configured by a gap formed between the rib and the protruding portion, for draining the condensation water stored in the water retaining portion to the drain pan outside the water retaining portion;
The air conditioner according to claim 1, wherein the capacity of the discharge section to discharge condensation water is set to be less than the amount of condensation water generated on the indoor heat exchanger during the cleaning cooling operation. 2. The air conditioner according to claim 1 , wherein the protrusion has a recess that is lower in height than the rib, the recess forming the exhaust portion. 3. The air conditioner according to claim 1 , wherein a heat insulating material is provided in the drain pan, and the water retaining portion and the discharge portion are formed in the heat insulating material.

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