JP3528760B2 - Heat exchanger cleaning device and air conditioner - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger cleaning device for removing dust and pollen adhering to a heat exchanger and suppressing the generation of bacteria, mold and the like, and an air conditioner including the same. Regarding the machine.

[0002]

2. Description of the Related Art Conventionally, maintenance work for cleaning a heat exchanger incorporated in an air conditioner has been very troublesome. Therefore, attempts have been made to reduce the maintenance by incorporating a heat exchanger cleaning function into the air conditioner. The cleaning operation may be started manually by a user operating a switch on the remote controller or may be automatically cleaned on a regular basis after counting the number of days.

[0003]

When the cleaning is performed manually, it is troublesome because it is troublesome for manpower. Moreover, the cleaning tends to be performed only after the odor is generated from the dust or the like adhering to the heat exchanger, which is symptomatic. On the other hand, when the cleaning is automatically performed on a regular basis, the cleaning is performed even when the heat exchanger is not so dirty and cleaning is not necessary.

Therefore, it is not preferable in terms of energy saving. Also,
The frequency of replenishing the cleaning liquid in a tank or the like containing the cleaning liquid increases, and maintenance becomes troublesome. On the contrary, in order to reduce the number of refills, it is necessary to make the tank large. The present invention has been made in view of the above problems, and an object of the present invention is to provide a heat exchanger cleaning device that can perform cleaning only when necessary, and an air conditioner including the same.

[0005]

[0006]

[Effect of the means and invention to solve the object described above
In order to achieve the above, the present invention provides means for cleaning the heat exchanger by applying cleaning liquid, and a control having an automatic cleaning mode for cleaning the heat exchanger based on the state quantity of the refrigerant flowing in the refrigerant circuit including the heat exchanger. Means and the state quantity of the refrigerant is a refrigerant
Ru der which is characterized in that it comprises a temperature. In this configuration, the state quantity of the refrigerant (the refrigerant
On the basis of the temperature (including temperature) , cleaning of the heat exchanger can be carried out only when cleaning is really needed. As a result, the heat exchange capacity of the heat exchanger can always be properly maintained. The frequency of replenishing the tank containing the cleaning liquid can be reduced, and the maintenance is reduced. Further, it is not necessary to use a large tank unnecessarily.

[0007] For example if, since the air conditioner so as to maintain the room temperature at a set temperature, heat transfer between the air passing through the heat exchanger dirty comes worse (i.e., the heat exchanger As the heat exchange capacity decreases, the condensation temperature and evaporation temperature of the refrigerant inevitably decrease. Therefore, if the state quantity of the refrigerant includes at least one of the condensation temperature and the evaporation temperature of the refrigerant (Claim 3 ), the cleaning can be performed at an appropriate timing that requires cleaning.

In particular, the control means may clean the heat exchanger when the condensation temperature is lower than the corresponding threshold value and the evaporation temperature is lower than the corresponding threshold value.
4 ) It is possible to more accurately predict the decrease in heat exchange capacity and perform cleaning at a more appropriate timing. The state quantity of the refrigerant may include the pressure of the refrigerant (claim 2 ).
In short, it is only necessary to look at the change in enthalpy, so the pressure that has a correlation with enthalpy (condensation pressure, evaporation pressure)
Based on the above, the appropriate cleaning timing can be determined as in the case of the above temperature.

Further, it further comprises means for detecting the temperature of the air before passing through the heat exchanger and means for detecting the temperature of the outside air, and the control means sets a threshold value based on the temperature of the air detected by these means. May be adjusted (Claims
5 ). In this case, the necessity of cleaning can be determined more appropriately. Further, the control means may further have a manual cleaning mode in which cleaning is performed in response to a signal from the manual switch (claim 6 ). In this case, the cleaning can be performed manually, which is preferable. In particular, it is preferable to further include means for selectively switching between the automatic cleaning mode and the manual cleaning mode (claim 7 ), because it is possible to switch between manual and automatic according to the user's request.

Further, the present invention may provide an air conditioner including the heat exchanger and the heat exchanger cleaning device according to any one of the above (claim 8 ). In this case, it is possible to realize an air conditioner that is small in size, inexpensive, and excellent in maintainability.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic cross-sectional view showing the internal configuration of an air conditioner incorporating a heat exchanger cleaning device according to an embodiment of the present invention. In this embodiment, the heat exchange cleaning device is a ceiling embedded type (cassette type) as an indoor unit.
An explanation will be given according to an example incorporated in the air conditioner 1 of
It is not limited to this.

Referring to FIG. 1, the air conditioner 1 comprises, for example, a ceiling-embedded type (cassette type) indoor unit, and has a casing 2 as a box-shaped air conditioner main body, and a lower surface of the casing 2. A decorative panel 3 which is connected to cover the opening 22 of the ceiling surface 21, a centrifugal blower 4 arranged in the central portion of the casing 2, and a fin-coil heat exchanger 5 arranged downstream of the periphery of the blower 4. A drain pan 6 disposed below the heat exchanger 5 for receiving the liquid falling from the heat exchanger 5, and a cleaning device A for cleaning the heat exchanger 5. 2a is a heat insulating material that covers the surface of the casing 2.

Although not shown, the above heat exchanger 5 and
A refrigerant circuit that circulates through the heat exchanger, the compressor, and the expansion valve of the outdoor unit is configured. The functions of the heat exchanger inside and outside are switched depending on whether it is cooling or heating, and one functions as a condenser and the other functions as an evaporator. A suction port 7 having a substantially rectangular shape is provided at the center of the decorative panel 3, and blowout ports 8 are provided on four sides around the suction port 7. Inside the casing 3, from the suction port 7, the air filter 9, the blower 4, and the heat exchanger 5
An air passage 10 is formed to reach the air outlet 8 via the. That is, when the blower 4 is driven, the suction port 7
The air sucked into the casing 2 through the air filter 9 is blown out in the centrifugal direction of the blower 4, flows between the fins 11 of the heat exchanger 5 to be heated or cooled, and is blown into the indoor space through the air outlet 8. It is like this.
The blower 4 includes a fan 4a and a motor 4 that drives the fan 4a.
b.

In FIG. 1, reference numeral 19 is a room temperature sensor including a thermistor for detecting the temperature of the air sucked from the suction port 7. An indoor heat exchange temperature sensor 20 detects the temperature of the refrigerant of the heat exchanger 5 built in the indoor unit. 23
Is a control box containing a control unit 17 for controlling the operation of the cleaning apparatus A. With reference to FIGS. 1, 2 and 3, the heat exchanger 5 includes a large number of fins 11 arranged in parallel with each other at a predetermined interval, and a large number of cooling holes for heat exchange that penetrate the fins 11. And a tube 12.

The cleaning device A includes the fins 11 of the heat exchanger 5.
A cleaning pipe 13 as a means for cleaning, which is arranged so as to penetrate through, is provided, and as shown in FIGS. 3 and 4,
On the peripheral surface 14 of the cleaning pipe 13, a large number of nozzles 15 are formed as a spraying unit for spraying the cleaning liquid flowing in the cleaning pipe 13 onto each fin 11 of the heat exchanger 5. Nozzle 1
In the case of No. 5, it can be easily formed by cutting and raising a part of the periphery of the hole formed on the peripheral surface 14 of the cleaning pipe 13. Further, in the case of the nozzle 15, it is possible to give the directionality of the jetting and to strongly spray the cleaning liquid on the fin 11, so that the cleaning ability can be enhanced.

As shown in FIG. 2, the cleaning device A is provided in the cleaning pipe 13 as the above-mentioned cleaning means, the tank 18 for containing the cleaning liquid L, and the path 16 from the tank 18 to the cleaning pipe 13. A pump P that pumps up the cleaning liquid L from the tank 18 and pressure-feeds it into the cleaning pipe 13, and a control unit 17 that controls the operation of a motor M that drives the pump P. The cleaning pipe 13 is configured as a dead end pipe that partially closes the cooling pipe 12. Since the cleaning pipe 13 is configured by using a part of the cooling pipe 12, the cleaning pipe 13 is replaced with the cooling pipe 12.
The structure can be simplified compared to the case where it is configured separately from
Also, the manufacturing cost can be reduced. One end of the cleaning pipe 13 is connected to the pump P and the tank 1 via the path 16 described above.
8 is connected.

The washing pipe 13 is the fin 1 of the heat exchanger 5.
1 is preferably arranged at least on the upper side.
This is because when placed on the upper part, the cleaning liquid sprayed on the upper part of the fin 11 reaches the lower part through the fin 11, and the injected cleaning liquid tends to spread downward, so that This is because the cleaning liquid can be spread over the entire area. That is, the cleaning liquid can be efficiently used. Further, the cleaning liquid may contain an antibacterial agent. In this case, generation of bacteria and mold can be effectively prevented, which is preferable. In particular, it is effective for cleaning drainage paths such as drain pans and drain hoses, and can prevent odor and slime from being generated in the drainage paths.

The control unit 17 includes a room temperature sensor 19,
The indoor heat exchange temperature sensor 20, the outdoor air temperature sensor 23 and the outdoor heat exchange temperature sensor 24 built in an outdoor unit (not shown) are connected. Each temperature sensor 19, 20, 2
When the control unit 17 which has received the detection signals from 3, 24 drives the motor M of the pump P when it determines that cleaning is necessary, it pumps the cleaning liquid L to the cleaning pipe 13 to clean the heat exchanger 5. To implement.

Next, the control operation will be described with reference to the flowchart of FIG. When the operation is started, the room temperature Tr and the outside air temperature Ta are input (step S1).
Next, based on the area determination map shown in FIG. 6, it is determined which one of a plurality (for example, nine) driving areas A1, A2, ... A9 corresponds to. Area A
1, A2, ..., A9 are respectively set in advance for the condensation temperature threshold T1 and the evaporation temperature threshold T2, the thresholds T1, T2 are determined according to the determined area (step S2). ). It should be noted that different types of maps are set depending on the time of cooling and the time of heating.

Next, the refrigerant condensation temperature Te and evaporation temperature T
c is input (step S3), and when the condensation temperature Te and the evaporation temperature Tc are both lower than the corresponding threshold values T1 and T2, respectively, a cleaning command is issued (steps S4 and S5). When the cleaning command is issued, the motor M is driven after the operation of the air conditioner 1 is stopped, and the cleaning is performed (steps S6 and S7). According to the present embodiment, the heat exchanger 5 can be washed only when it is truly necessary to wash it, based on the state quantity of the refrigerant that has the strongest correlation with the heat exchange capacity. Thereby, the heat exchange capacity of the heat exchanger 5 can always be maintained appropriately. It is possible to reduce the frequency of replenishing the tank 18 containing the cleaning liquid, and reduce the maintenance. Further, it is not necessary to use the large tank 18 unnecessarily, and the size can be reduced.

Particularly, when the detected condensation temperature Te is lower than the corresponding threshold value T1 and the detected evaporation temperature Tc is lower than the corresponding threshold value T2, the heat exchanger 5 is cleaned. Therefore, it is possible to more accurately predict the decay of the heat exchange capacity and perform the cleaning at a more appropriate timing. Moreover, since the above threshold values T1 and T2 are adjusted based on the room temperature Tr and the outside air temperature Ta, it is possible to more appropriately determine the timing at which cleaning is necessary.

Further, since the cleaning pipe 13 is laid out so as to penetrate each fin 11 of the heat exchanger 5, the size can be made smaller than the conventional one. Further, the cleaning pipe 13 is the fin 1
Since the cleaning liquid is sprayed from a position close to 1, the cleaning liquid does not unnecessarily splatter, and therefore it is not necessary to provide a drip-proof cover, and as a result, the number of parts can be reduced and the manufacturing cost can be reduced. You can In addition, by incorporating the small and inexpensive cleaning device A into the air conditioner 1,
It is possible to provide the air conditioner 1 that is small in size, inexpensive, and excellent in maintainability.

Although a structure for supplying rinsing water for flushing the cleaning liquid has been used conventionally, this embodiment does not have a structure for supplying rinsing water. In this, it is during the cooling season that the contamination of the heat exchanger 5 is significantly exposed, and during the cooling season, the fins 11 of the heat exchanger 5 are exposed.
It is based on the idea that a separate mechanism for supplying rinse water is unnecessary because the condensed water adhering to the can be used as rinse water. However, the present invention is not intended to prevent adding a structure for supplying rinse water.

In the above-described embodiment, the cleaning timing is determined by using both the condensation temperature Te and the evaporation temperature Tc, but the present invention is not limited to this, and the condensation temperature Te and the evaporation temperature Tc are not limited thereto.
It is also possible to determine the cleaning timing based on the comparison between any one of the above and the corresponding threshold values T1 and T2. Further, in FIG. 5, the condensation pressure Pe is used instead of the condensation temperature Te, and the evaporation pressure P is used instead of the evaporation temperature Tc.
c, and further, instead of the temperature thresholds T1 and T2 of the condensation temperature and the evaporation temperature, the condensation pressure and the evaporation pressure threshold P
It is also possible to judge the cleaning timing by using 1, P2 (see the block diagram of FIG. 7). Also in this case, the cleaning timing can be determined based on the comparison between at least one of the condensation pressure Pe and the evaporation pressure Pc and the corresponding threshold values P1 and P2. The condensation pressure sensor 25 for detecting the condensation pressure Pe and the evaporation pressure Pc
The evaporation pressure sensor 26 for detecting the
And the heat exchanger (not shown) of the outdoor unit.

Next, FIGS. 8 and 9 show another embodiment of the present invention. In the present embodiment, a remote control 27 equipped with various operation keys of the air conditioner 1 is provided with a manual cleaning switch 28, and a manual cleaning mode for performing cleaning according to a signal from the cleaning switch 28 is provided. It is in. Specifically, the flow is as shown in FIG. 9, and step S8 is added to the flowchart shown in FIG. That is, the conditions in step S4 and the cleaning switch 2
Cleaning is performed when any one of the conditions for turning on 8 is satisfied. In this case, the cleaning can be performed manually, which is preferable.

In this case, as a means for selectively switching between the automatic cleaning mode and the manual cleaning mode, a changeover switch 29 is added to the remote controller 27 as shown in FIG. 10, and a changeover switch 29 is shown as shown in FIG. Alternatively, the automatic cleaning mode step (steps S2 to S9) and the manual cleaning mode (steps S11, S12, S7 to S9) may be switched based on the signal from (step S1). It is preferable that the manual mode and the automatic mode can be switched according to the user's request. Note that steps S3 to S in FIG.
9 corresponds to steps S1 to S7 in FIG. In the manual cleaning mode, a cleaning command is issued in response to turning on the cleaning switch 28.

The present invention is not limited to the above embodiments. For example, in the embodiment of FIG. 5 and FIG. 9, the cleaning command is issued immediately after the condition of step S4 is satisfied once, but the present invention is not limited to this, and a plurality of times (for example, 6 times).
The cleaning command may be issued only when the condition is satisfied. This is to ensure the detection of conditions for issuing a cleaning command,
This is to prevent careless cleaning. The same applies to the condition of step S6 in FIG.

Besides, various modifications can be made within the scope of the present invention.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an air conditioner including a heat exchanger cleaning device according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram schematically showing a heat exchanger and a cleaning device.

FIG. 3 is a partially cutaway perspective view of a main part of the cleaning device.

FIG. 4 is a cross-sectional view of a heat exchanger and a cleaning pipe.

FIG. 5 is a flowchart showing a flow of control for determining necessity of cleaning.

FIG. 6 is a diagram showing an area map of threshold values.

FIG. 7 is a block diagram showing an electrical configuration of another embodiment of the present invention.

FIG. 8 is a block diagram showing an electrical configuration of still another embodiment of the present invention.

9 is a flowchart of control in the embodiment of FIG.

FIG. 10 is a block diagram showing an electrical configuration of another embodiment of the present invention.

FIG. 11 is a block diagram showing an electrical configuration of still another embodiment of the present invention.

[Explanation of symbols]

1 air conditioner 2 Casing (air conditioner body) 5 heat exchanger 10 wind path 11 fins 12 Cooling pipe 13 Washing pipe (means for washing) 14 circumference 15 nozzles (spraying means) 16 routes 17 Control unit 18 tanks 19 Room temperature sensor 20 Indoor heat exchange temperature sensor 23 Outside temperature sensor 24 Outdoor heat exchange temperature sensor A cleaning device L cleaning liquid P pump M motor Te condensation temperature Tc evaporation temperature T1, T2 threshold Tr room temperature Ta outside temperature Pe Condensation pressure Pc Evaporation pressure P1, P2 threshold

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-7-98144 (JP, A) JP-A-11-337105 (JP, A) JP-A-10-325621 (JP, A) JP-A-6- 109315 (JP, A) Actual development 61-10431 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F24F 11/02 102

Claims (8)

(57) [Claims] 1. A means (13) for applying a cleaning liquid to a heat exchanger (5) for cleaning, and a refrigerant circuit including the heat exchanger (5).
Based on the state quantity of the refrigerant and control means (17) having an automatic cleaning mode for cleaning the heat exchanger (5) that, on
The state quantity of the refrigerant (Te, Tc, Pe, Pc) is the temperature of the refrigerant.
A heat exchanger cleaning device characterized in that the heat exchanger cleaning device includes a temperature (Te, Tc) . 2. A state quantity (Te, Tc, Pe, P ) of the refrigerant.
c) is characterized by including the pressure (Pe, Pc) of the refrigerant
The heat exchanger cleaning device according to claim 1 . 3. A state quantity (Te, Tc, Pe, P ) of the refrigerant.
c) has a low condensation temperature (Te) and a low evaporation temperature (Tc).
At least one is included, The claim 1 or 2 characterized by the above-mentioned.
Heat exchanger cleaning apparatus. 4. The condensing temperature (Te) is controlled by the control means (17) .
Lower than the corresponding threshold (T1) and the evaporation temperature (Tc) is
It is lower than the corresponding threshold value (T2) heat exchanger (5)
The heat exchanger cleaning device according to claim 3, which is cleaned. 5. The air before passing through the heat exchanger (5)
Means for detecting temperature (19) and hand for detecting temperature of outside air
A stage (23) is further provided, detected by these means.
Control means (1) based on the temperature (Tr, Ta) of the air
7) adjusts thresholds (T1, T2)
The heat exchanger cleaning device according to claim 4 . 6. The control means (17) is a manual cleaning switch.
Manual washing to perform washing according to the signal from H (28)
The method according to claim 1, further comprising a cleaning mode.
6. The heat exchanger cleaning device according to any one of 5) . 7. The automatic cleaning mode and the manual cleaning mode are selected.
It is characterized in that it further comprises means (29) for single switching.
The heat exchanger cleaning device according to claim 6, which is a characteristic . 8. A heat exchanger (5) and any one of claims 1 to 7.
Including a heat exchanger cleaning device (A) according to any one of them
A characteristic air conditioner.