JP3711667B2 - Air conditioner - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for controlling a blower fan of an outdoor unit, particularly in an air conditioner.
[0002]
[Prior art]
Conventionally, as a method for controlling a blower fan of an outdoor unit of an air conditioner, there is one described in Japanese Patent Laid-Open No. 7-212902 (hereinafter referred to as a gazette device). The air conditioner in this gazette device is such that the rotation speed of the compressor is variable according to the air conditioning load, and the method of controlling the blower fan is as follows.
[0003]
In the above-mentioned publication device, for example, when the air conditioner is in cooling, control is performed so that the air flow rate of the blower fan increases as the outside air temperature Tam increases. Specifically, the blower fan has hysteresis, and when the outside air temperature Tam is higher than 25 ° C., the air blowing amount is set to the Hi level, and when the outside air temperature Tam is lower than 22 ° C., the air blowing amount is set to the Lo level. So that it is controlled.
[0004]
[Problems to be solved by the invention]
However, the above publication apparatus has the following problems. That is, in the above publication apparatus, the air blowing amount of the blower fan is uniquely controlled by the outside air temperature Tam regardless of the state of the air conditioner. For example, when the outside air temperature Tam is very high, The blower fan becomes Hi level. As a result, there is a problem that noise due to driving of the blower fan is noticeable.
[0005]
That is, when the outside air temperature Tam is very high and the cooling load of the air conditioner is large, the rotational speed of the compressor of the air conditioner also increases, and the noise of the blower fan is not so noticeable due to the rotational noise of the compressor. On the other hand, even if the outside air temperature Tam is very high, when the cooling load is small, the rotational speed is low and the compressor rotating noise is reduced, so that the noise of the blower fan is particularly noticeable.
[0006]
[Means for Solving the Problems]
As a result of the examination of the above-mentioned publication device by the present inventors, when the rotation speed of the compressor is low and the cooling load is small, the condensation in the outdoor unit is sufficiently completed even if the air blowing amount of the blower fan is not set to the Hi level. It was found that there was no shortage of cooling capacity.
[0007]
Then, an object of this invention is to reduce the noise of a ventilation fan. In the first and second aspects of the invention, the air blowing control means (40) controls the rotational speed of the blower fan (29) to be smaller as the rotational speed of the compressor (21) is smaller. It is said.
[0008]
Thus, the air blow control means, as the rotation speed of the compressor is reduced, as the means that the air conditioning load is reduced, since it is controlled so that the rotational speed of the blower fan is reduced, without affecting the air conditioning capability of the air conditioner Furthermore, the noise of the blower fan can be reduced. Further, in the invention 請 Motomeko 1, wherein blower control means (40) includes a first rotational speed which the first rotating speed setting means (210) is set, the second rotational speed setting means (220) is set The blower fan (29) is controlled so as to be the smaller one of the second rotational speeds.
[0009]
Thus, the first rotation speed setting means sets the first rotation speed of the blower fan based on the outside air temperature, and the second rotation speed setting means sets the first fan rotation speed based on the rotation speed of the compressor (21). 29) is set. And a ventilation control means controls a ventilation fan so that it may become the rotation speed of the smaller one among the said 1st rotation speed and 2nd rotation speed.
[0010]
As a result, for example, even if the first rotation speed setting means sets the first rotation speed of the blower fan to a large value based on the outside air temperature, the rotation speed of the compressor is low and the second rotation speed setting means has the second rotation speed. Is set to a small value, the blower fan is controlled so as to achieve the second rotational speed, so that the noise of the blower fan can be reduced.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below with reference to embodiments shown in the drawings.
In the present embodiment, the present invention is applied to an air conditioner for an electric vehicle.
The air conditioning duct 2 in the air conditioning unit 1 of FIG. 1 constitutes an air passage that guides air into the vehicle interior, and is provided with an inside / outside air switching means 3 and a blower means 4 on one end side and communicates with the vehicle interior on the other end side. A plurality of air outlets 14 to 16 are formed.
[0012]
The inside / outside air switching means 3 is provided in an inside / outside air switching box in which an inside air suction port 5 for sucking air inside the vehicle compartment (inside air) and an outside air suction port 6 for sucking air outside the vehicle compartment (outside air) are formed. An inside / outside air switching door 7 that selectively opens and closes the suction ports 5 and 6 is provided, and the inside / outside air switching door 7 is driven by its driving means (not shown, for example, a servo motor).
[0013]
The air blowing means 4 generates an air flow in the air conditioning duct 2 from the inside air inlet 5 or the outside air inlet 6 toward the air outlets 14 to 16. Is provided with a centrifugal multiblade fan 9 and this fan 9 is driven by a motor 10 as a driving means thereof.
In addition, a cooling indoor heat exchanger 11 is provided in the air conditioning duct 2 on the air downstream side of the fan 9. This cooling indoor heat exchanger 11 is a heat exchanger that constitutes a part of a refrigeration cycle 20 described later, and in the cooling operation mode described later, air in the air-conditioning duct 2 is removed by the evaporating action of the refrigerant flowing inside. Functions as an evaporator for dehumidification and cooling. Note that the refrigerant does not flow in the cooling indoor heat exchanger 11 in the heating operation mode described later.
[0014]
A heating indoor heat exchanger 12 is provided in the air conditioning duct 2 on the air downstream side of the cooling indoor heat exchanger 11. This heating indoor heat exchanger 12 is a heat exchanger that constitutes a part of the refrigeration cycle 20, and heats the air in the air-conditioning duct 2 by the condensing action of the refrigerant flowing inside during the heating operation mode described later. Functions as a condenser. Note that the refrigerant does not flow in the indoor heat exchanger 12 for heating in the cooling operation mode described later.
[0015]
Further, in the air conditioning duct 2, the amount of air that is pumped from the fan 9 and that flows through the heating indoor heat exchanger 12 and the amount that bypasses the air at the position adjacent to the heating indoor heat exchanger 12. An air mix door 13 for adjusting the above is provided. The air mix door 13 is controlled by the control device 40 (FIG. 2) to a position where all of the pumped air from the fan 9 bypasses the heating indoor heat exchanger 12 in the cooling operation mode described later. In the heating operation mode to be performed, all of the pumped air from the fan 9 is controlled to a position where it passes through the heating indoor heat exchanger 12.
[0016]
Moreover, each said blower outlets 14-16 specifically, the defroster blower outlet 14 which blows off conditioned air to the inner surface of a vehicle windshield, the face blower outlet 15 which blows off conditioned air toward the passenger | crew's upper body, It is the foot blower outlet 16 which blows off air-conditioning air toward the lower body of a passenger in the passenger compartment. Moreover, the doors 17-19 which open and close these blower outlets are provided in the air upstream side site | part of these blower outlets.
[0017]
The refrigeration cycle 20 is a heat pump refrigeration cycle that cools and heats the passenger compartment with the cooling indoor heat exchanger 11 and the heating indoor heat exchanger 12, and in addition to these heat exchangers 11 and 12, Are provided with a refrigerant compressor 21, an outdoor heat exchanger 22, a cooling decompression device 23, a heating decompression device 24, an accumulator 25, and a four-way valve 26 for switching the refrigerant flow, and these are connected by a refrigerant pipe 27. It has become. In the drawings, 28 is an electromagnetic valve, 29 in the outdoor blower fan, 29a is an electric motor for driving the outdoor blower fan 29.
[0018]
The refrigerant compressor 21 sucks, compresses and discharges the refrigerant when driven by the electric motor 30 (three-phase AC synchronous motor in this embodiment). The electric motor 30 is disposed in the sealed case integrally with the refrigerant compressor 21, and the rotation speed is continuously varied by being controlled by the inverter 31. The inverter 31 is energized and controlled by the control device 40 (FIG. 2).
[0019]
As shown in FIG. 2, the control device 40 includes a post-passage air temperature sensor that detects the degree of air cooling in the cooling indoor heat exchanger 11 (specifically, the air temperature immediately after passing through the heat exchanger 11). 41, from a compressor rotational speed sensor 42 for detecting the rotational speed of the compressor 21, an input current sensor 43 for detecting the amount of current input to the inverter 31, and a high pressure sensor 44 for detecting a high pressure on the discharge side of the compressor 21. Each signal is input.
[0020]
In addition to the signals from the sensors 41 to 44, the control device 40 includes an internal air temperature sensor that detects the air temperature in the passenger compartment as an environmental factor detector that detects an environmental factor that affects the air-conditioning environment. 45, the outside air temperature sensor 46 for detecting the outside air temperature, and each signal from the solar radiation sensor 47 for detecting the amount of solar radiation radiated into the vehicle interior, and each lever of the control panel 51 provided on the front surface of the vehicle interior The signal from the switch is also input.
[0021]
As shown in FIG. 3, the control panel 51 includes a blowing mode setting lever 52 for setting each blowing mode, an air volume setting lever 53 for setting the amount of air blown into the vehicle interior, and an inside / outside air setting mode for the inside / outside air switching mode. A switching lever 54, a cooling / heating mode setting switch 55 including a cooling switch 55a for setting the refrigeration cycle 20 in the cooling operation mode and a heating operation mode 55b, and a temperature setting lever 56 for adjusting the temperature of the blown air into the vehicle compartment are provided.
[0022]
2 is provided with a well-known microcomputer comprising a CPU, ROM, RAM, etc. (not shown). The signals from the sensors 41 to 47 and the signals from the control panel 51 are as follows. The data is input to the microcomputer through an input circuit (not shown) in the ECU. And this microcomputer performs the predetermined process mentioned later, and controls each said drive means, such as the inverter 31, based on the process result. The control device 40 is supplied with power from a battery (not shown) when a key switch (not shown) of the automobile is turned on.
[0023]
By the way, when the cooling switch 55a is turned on by a passenger in the vehicle interior, the microcomputer controls the four-way valve 26 and the electromagnetic valve 28, and the refrigeration cycle 20 enters the cooling operation mode. In this mode, the refrigerant flows in the order of the compressor 21 → the outdoor heat exchanger 22 → the cooling decompressor 23 → the cooling indoor heat exchanger 11 → the accumulator 25 → the compressor 21.
[0024]
When the heating switch 55b is turned on by a passenger in the vehicle interior, the microcomputer controls the four-way valve 26 and the electromagnetic valve 28, and the refrigeration cycle 20 enters the heating operation mode. In this mode, the refrigerant flows in the order of the compressor 21 → the heating indoor heat exchanger 12 → the heating decompression device 24 → the outdoor heat exchanger 22 → the electromagnetic valve 28 → the accumulator 25 → the compressor 21.
[0025]
Next, control processing of the inverter 31 performed by the microcomputer will be described with reference to FIG.
First, when the key switch is turned on to supply power to the control device 40 and the air volume setting lever 53 is set to a position of a predetermined air volume other than OFF, the routine of FIG. And make initial settings. In the next step 120, signals from the sensors 41 to 47 and the levers and switches of the control panel 51 are read.
[0026]
Next, in step 130, it is determined whether or not the cooling switch 55a is turned on. If the cooling switch 55a is turned on, the routine proceeds to step 140 to set the cooling operation mode.
In step 140, a target blowout temperature TEO (hereinafter referred to as TEO) into the passenger compartment is determined from the following formula 1.
[0027]
[Expression 1]
TEO = Kset * Tset-Kr * Tr-Kam * Tam-Ks * Ts-C
Tset is the set temperature determined by the setting position of the temperature setting lever 56, Tr is the inside air temperature detected by the inside air temperature sensor 45, Tam is the outside air temperature detected by the outside air temperature sensor 46, and Ts is detected by the solar radiation sensor 47. The amount of solar radiation. Kset, Kr, Kam, and Ks are gains, and C is a constant.
[0028]
Next, at step 150, the target rotational speed Nc of the refrigerant compressor 21 is calculated such that the air temperature blown from the actual cooling indoor heat exchanger 11 becomes the TEO determined at step 140. After that, the routine proceeds to step 160 where the actual rotation speed of the refrigerant compressor 21 detected by the compressor rotation speed sensor 42 is controlled by the inverter 31 so as to become the target rotation speed Nc calculated at step 150. The The target rotational speed Nc can be considered as an index representing the cooling load in the passenger compartment in the cooling operation mode.
[0029]
On the other hand, if the decision result in the step 130 is NO, the process proceeds to a step 170. In step 170, it is determined whether or not the heating switch 55b is turned on. Then, when the heating switch 55b is turned on, the routine proceeds to step 180 in order to set the heating operation mode.
In step 180, a high target high pressure on the discharge side of the compressor 21 is determined. In the present embodiment, since the high pressure on the discharge side of the compressor 21 is naturally related to the refrigerant temperature, the target high pressure can also be said to be the target refrigerant temperature. The target high pressure is calculated so as to increase as the temperature setting lever 56 is operated to the right side (hot side) in FIG.
[0030]
Next, in step 190, the target rotational speed Nh of the refrigerant compressor 21 is calculated so as to be the target high pressure determined in step 180. Naturally, the target rotational speed Nh is calculated so as to increase as the temperature setting lever 56 is operated to the right side (hot side) in FIG. Further, the target rotational speed N h can be considered as an indicator of the heating load of the passenger compartment in the heating operation mode.
[0031]
Thereafter, the routine proceeds to step 160, the rotation speed of the actual refrigerant compressor 21 compressor rotational speed sensor 42 by the inverter 31 is detected, control so that the target speed N h calculated in step 190 Is done. In the following, a description will be given of the control of the outdoor blower fan 29 is a main part of the present invention. In step 200, the amount of air blown by the outdoor blower fan 29 is determined. This content will be described with reference to the flowchart shown in FIG.
[0032]
First, in step 210, the first air volume (the air blowing level, the applied voltage of the fan motor 29a, the rotation speed of the outdoor air blowing fan 29a) is set by the outside air temperature Tam detected by the outside air temperature sensor 46. And this 1st ventilation volume is specifically determined from the characteristic view shown in FIG.
That is, in the cooling operation mode as shown in FIG. 6, when the outdoor air temperature Tam is higher than 25 ° C., the air blowing amount of the outdoor air blowing fan 29 is set to the Hi level (in this embodiment, the rotational speed of the outdoor air blowing fan). To do. Further, when the outside air temperature Tam is lower than 22 ° C., the air blowing amount of the outdoor air blowing fan 29 is set to Lo level (in this embodiment, the rotational speed of the outdoor air blowing fan). The reason why the characteristic has hysteresis as shown in FIG. 6 is to prevent hunting of the outdoor blower fan 29.
[0033]
On the other hand, in the heating operation mode as shown in FIG. 7, when the outside air temperature Tam is higher than 16 ° C., the air blowing amount of the outdoor air blowing fan 29 is set to the Lo level (in this embodiment, the rotation speed of the outdoor air blowing fan). To do. When the outdoor air temperature Tam is lower than 12 ° C., the air blowing amount of the outdoor air blowing fan 29 is set to the Hi level (in this embodiment, the rotational speed of the outdoor air blowing fan). The reason why the characteristic has hysteresis as shown in FIG. 7 is to prevent hunting of the outdoor blower fan 29.
[0034]
Next, in step 220, the second air blowing amount (the air blowing level, the applied voltage of the fan motor 29a, the rotation speed of the outdoor air blowing fan 29a) is set by the target rotation speeds Nc and Nh calculated in step 150 or 190. . And the 2nd ventilation volume is specifically determined from the characteristic view shown in FIG. Then, the second air blowing amount, the target rotational speed Nc, as shown in FIG. 8, Nh large Do Ruhodo, is set to be larger. And in this embodiment, 2nd ventilation volume is set to two steps, Lo and Hi. Note that Lo and Hi are the same as the air flow shown in FIGS.
[0035]
Then, the process proceeds to step 230, and the outdoor blower fan is set so that the smaller one of the first blower amount set in step 210 and the second blower amount set in step 220 becomes the final blower amount. 29 (fan motor 29a) is controlled.
The operation in the present embodiment will be described. When the air conditioner has a very high outside air temperature Tam, for example, 26 ° C., and is air-conditioned in the cooling operation mode, in step S210, the outdoor air blowing fan 29 performs the first sending. The air volume is set to Hi. However, for example, even if the outside air temperature Tam is high, the cooling load (target rotational speed Nc) is not so large in a state where the passenger compartment is sufficiently cooled. Therefore, the target rotational speed Nc calculated in step 150 may be reduced, and the second air flow rate set in step 220 may be Lo.
[0036]
Therefore, conventionally, when the outside air temperature Tam is high, the air blowing amount of the outdoor air blowing fan 29 is always Hi, and thus there is a problem that the noise of the outdoor air blowing fan 29 becomes conspicuous. However, in this embodiment, in such a case, since the smaller of the first air flow rate and the second air flow rate, that is, Lo in the description, in Step 230, the noise of the outdoor fan 29 can be reduced. .
[0037]
Also in the heating operation mode, when the outside air temperature Tam is low, for example, 10 ° C., the first air blowing amount of the outdoor air blowing fan 29 is set to Hi in step S210. However, for example, even when the outside air temperature Tam is low, the heating load (target rotational speed Nh) is not so large in a state where the vehicle interior is sufficiently heated. Accordingly, the target rotational speed N h calculated in Step 1 90 may be reduced, and the second air flow rate set in Step 220 may be Lo.
[0038]
In this embodiment, in such a case, since the smaller one of the first air flow rate and the second air flow rate, that is, Lo in the description, in step 230, the noise of the outdoor air blowing fan 29 can be reduced. .
Moreover, in this embodiment, since it applied to the air conditioner for electric vehicles, since the ventilation volume of the outdoor ventilation fan 29 becomes small compared with the past, ie, the voltage applied to the fan motor 29a is lowered, it is mounted on the vehicle. Thus, the consumption of the used battery can be reduced, and the travel distance of the vehicle can be extended.
[0039]
(Other embodiments)
In the above embodiment, Lo and Hi set at the target rotational speeds Nc and Nh as shown in FIG. 8 and Lo and Hi set at the outside air temperature Tam as shown in FIGS. Although the air volume is used, it may be different.
Moreover, in the said embodiment, although the 2nd ventilation volume set with the target rotation speed Nc and Nh was made into two steps, you may make it vary linearly.
[0040]
Moreover, in the said embodiment, although the 1st ventilation volume set with the external temperature Tam was made into two steps, you may make it vary linearly.
Further, the present invention may be applied to a home or business use air conditioner regardless of the electric vehicle air conditioner.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an air conditioner according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a control device in the embodiment.
FIG. 3 is a diagram showing a control panel in the embodiment.
FIG. 4 is a flowchart showing control details in the embodiment.
FIG. 5 is a flowchart showing control contents in the embodiment.
FIG. 6 is a diagram illustrating a correlation between an outside air temperature Tam and a first air flow rate in the cooling operation mode in the embodiment.
FIG. 7 is a diagram illustrating a correlation between an outside air temperature Tam and a first air flow rate in the heating operation mode in the embodiment.
FIG. 8 is a diagram illustrating a correlation between target rotation speeds Nc and Nh in the cooling operation mode and the heating operation mode in the embodiment and the second air blowing amount.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Indoor heat exchanger for cooling, 12 ... Indoor heat exchanger for heating 21 ... Refrigerant compressor, 22 ... Outdoor heat exchanger, 23, 24 ... Pressure reducing device 29 ... Outdoor ventilation fan, 40 ... Control device.

Claims (2)

At least the compressor (21), an outdoor heat exchanger (22), the decompressor (23, 24), blowing fan indoor heat exchanger (12), and toward the chamber outer heat exchanger (22) for blowing air (29) It has a ventilation control means (40) for controlling the rotational speed of the blower fan (29) , and variably controls the rotational speed of the compressor (21) according to the air conditioning load to air-condition the conditioned space. In the air conditioner,
The air blowing control means (40) is a first rotation speed setting means (210) for setting the first rotation speed of the blower fan (29) based on the outside air temperature (Tam), and the rotation of the compressor (21). The second rotational speed setting for setting the second rotational speed of the blower fan (29) so that the rotational speed of the blower fan (29) becomes smaller as the rotational speed of the compressor (21) becomes smaller based on the number. Means (220), and the first rotational speed set by the first rotational speed setting means (210) and the second rotational speed set by the second rotational speed setting means (220), The air conditioner characterized by controlling the said ventilation fan (29) so that it may become the rotation speed of the smaller one . Environmental factor detection means (45-47, 51) for detecting an air conditioning environment factor that affects the air conditioning environment;
And target rotational speed calculation means (150, 190) for calculating the target rotational speed (Nc, Nh) of the compressor (21) based on the air conditioning environmental factor detected by the environmental factor detection means (120). ,
The second rotation speed setting means (220) decreases the rotation speed of the blower fan (29) as the target rotation speed (Nc, Nh) calculated by the target rotation speed calculation means (150, 190) decreases. The air conditioner according to claim 1 , wherein the second rotational speed of the blower fan (29) is set so as to be.

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