JPH0719617A - Air current velocity adjusting device of condenser fan - Google Patents

Abstract

PURPOSE:To provide an air current velocity adjusting device of a condenser fan capable of effectually preventing sleeping from being arrested owing to noise from the condenser fan at night in summer. CONSTITUTION:There are provided a condenser temperature sensor 14 for detecting the temperature of a condenser 3, a controller 16 for adjusting the number of revolutions of a condenser fan 11 with predetermined standard characteristics based upon an output of the condenser temperature sensor 14, and an outside air temperature sensor 14 for detecting the outside air temperature. The controller 16 controls the number of revolutions of the condenser fan 11 based upon an output of the outside air temperature sensor 17 with characteristics which ensures low noise compared with standard characteristics, in the case of the outside air temperature corresponding to the one at night in summer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed adjusting device for a blower for a condenser for air-cooling a condenser used in an air conditioner / refrigerator such as an air conditioner or a showcase.

[0002]

2. Description of the Related Art Conventionally, in an air conditioner such as this type of air conditioner, a compressor and a condenser constituting a refrigeration cycle are installed outdoors, and an evaporator is installed indoors. In addition, since the high temperature gas refrigerant discharged from the compressor flows into the condenser and condenses and liquefies there, the condenser is conventionally provided with a condenser blower, and the condenser is forcedly air-cooled by the outside air. is doing.

Here, if the air-cooling of the condenser by the condenser blower is insufficient, the condensing pressure (high pressure) rises abnormally, which makes it impossible to obtain a predetermined refrigerating capacity and damages the equipment. On the contrary, if the air cooling is excessive, the condensing pressure cannot be raised, the low pressure of the refrigeration cycle drops abnormally, and the so-called short cycle operation occurs in which the low pressure switch repeatedly turns on and off in a short period of time. Cause damage.

Therefore, conventionally, a condenser temperature sensor for detecting the temperature (condensation temperature) is provided in the pipe portion of the condenser, and a standard device as shown in FIG. 2 is provided by the controller based on the output signal of the condenser temperature sensor. The rotational speed of the blower for the condenser was adjusted by the characteristic rotational speed characteristic. That is, the condensation temperature C
When T is high, the rotation speed N of the condenser blower is increased to increase the rotation speed, and the rotation speed N is decreased as the condensation temperature CT decreases, thereby appropriately cooling the condenser with air. is there.

[0005]

By the way, in summer, the outside air temperature rises throughout the day and night compared to other seasons, so the condensation temperature also rises. Therefore, the control device tends to maintain the rotation rate of the condenser blower at a high level, and the noise thereof becomes relatively large. However, in summer, many ordinary households sleep by opening windows, and there is a problem that the blower for the condenser of the adjacent house, which emits a large amount of noise as described above, prevents sleeping.

The present invention has been made to solve the above-mentioned conventional technical problems, and can effectively prevent the sleep from being disturbed by the noise of the condenser blower at night in summer. An object of the present invention is to provide a speed adjusting device for a ventilation fan.

[0007]

That is, the speed adjusting device for a condenser blower of the present invention constitutes a refrigeration cycle by connecting a compressor, a condenser, a decompressor and an evaporator in sequence in an annular fashion, and also a condenser. It is applied to those provided with a blower for a condenser for air cooling, and a condenser temperature sensor for detecting the temperature of the condenser, and based on the output of this condenser temperature sensor,
A controller for adjusting the number of revolutions of the condenser blower with predetermined standard characteristics, and an outside air temperature sensor for detecting the outside air temperature are provided, and the controller is based on the output of the outside air temperature sensor-
In the case of an outside temperature corresponding to the nighttime in summer, the rotation speed of the condenser blower is controlled by the characteristic that the noise is lower than the standard characteristic.

[0008]

According to the speed adjusting device for a condenser blower of the present invention, the control device has a standard characteristic when the outside temperature is equivalent to the nighttime in summer, based on the output of the outside temperature sensor for detecting the outside temperature. Since the rotation speed of the condenser blower is controlled with the characteristic of lower noise, the noise generated by the condenser blower can be suppressed to a low level during the summer night, and when the neighbor's house opens the window and sleeps. It is possible to solve the noise problem that occurs in the above. In particular, since the rotation speed control of the condenser blower is automatically switched, the operability is improved as compared with, for example, the case where it is manually switched, and the switching is performed only for a necessary period, so that, for example, with the characteristic of low noise throughout the year. It is possible to reduce an increase in power consumption due to an increase in condensing pressure as compared with the case of controlling.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a refrigerant circuit diagram of a refrigerating cycle of an air conditioner AC as an embodiment to which the speed adjusting device 18 of the present invention is applied, FIG. 2 is a view showing a rotational speed control characteristic of a condenser blower 11, and FIG. 3 is a speed adjusting device 18 4 is a flowchart showing a program of the control device 16 constituting the above. In FIG. 1, a pipe 4 constituting a condenser 3 is connected to a discharge side pipe 2 of a compressor 1 including a rotary compressor, a scroll compressor and the like, and an outlet side of the condenser 3 is connected to a pressure reducing device via a pipe 6. Is connected to the expansion valve 7. The expansion valve 7 is connected to the evaporator 8, and the outlet side of the evaporator 8 is connected to the compressor 1 to form an annular refrigeration cycle.

The condenser 3 includes a heat exchanger 9 in which the pipe 4 is inserted through a plurality of heat exchange fins, and a condenser blower 11.
The condenser blower 11 includes a motor 12 and a propeller fan 13. The evaporator 8 is installed indoors, and the compressor 1 and the condenser 3 are installed outdoors. A condenser temperature sensor-14 is attached to the pipe 4 of the heat exchanger 9 of the condenser 3, and the condenser temperature sensor-14 is connected to the controller 16 of the condenser blower 11. The control device 16 is further connected to an outdoor temperature sensor 17 for detecting the outdoor temperature where the condenser 3 is installed, that is, the outdoor air temperature. The control device 16, the condenser temperature sensor 14 and the outdoor air temperature sensor 17 A speed adjusting device 18 of the condenser blower 11 is configured.

When the compressor 1 is started, the high temperature and high pressure gas refrigerant discharged from the compressor 1 flows into the heat exchanger 9 of the condenser 3 through the pipe 2. As will be described later, the heat exchanger 9 is ventilated with outside air from the condenser blower 11, and the refrigerant flowing into the heat exchanger 9 is air-cooled and condensed and liquefied. Condenser 3
The refrigerant discharged from the refrigerant reaches the expansion valve 7 via the pipe 6, is decompressed there, and then flows into the evaporator 8 to be evaporated there. The room is cooled by the endothermic action at this time. Then, the refrigerant discharged from the evaporator 8 is sucked into the compressor 1. The compressor 1
A low pressure switch (not shown) is provided on the suction side (low pressure side) of the compressor 1, and the compressor 1 is operated / stopped by detecting the upper and lower limits of the set pressure (low pressure side).

Next, the rotation speed control of the condenser blower 11 by the control device 16 of the speed adjusting device 18 will be described with reference to FIG. In step S1, the controller 16 inputs the temperature of the heat exchanger 9 of the condenser 3, that is, the condensation temperature CT based on the output signal of the condenser temperature sensor 14. Next, in step S2, the outside air temperature AT is input based on the output signal of the outside air temperature sensor 17, and in step S3, the outside air temperature AT is input.
Is within the range of + 21 ° C to + 27 ° C.

When the outside air temperature AT is out of the range of + 21 ° C. to + 27 ° C., the control device 16 proceeds to step S4 and selects the rotation speed from the predetermined standard characteristic, and at step S5 the motor 12 is selected. To drive the motor 12. That is, in step S4, as shown in FIG. 2, the condensing temperature CT is + 50 ° C. or more, the rotation rate N is set to 100%, the motor 12 is rotated at full speed, and the condensing temperature CT is +.
The rotation speed N is set to 0% by decreasing to 10 ° C., and the rotation speed of the motor 12 of the condenser blower 11 is selected based on the linear characteristic of stopping the motor 12. Thereby, the condenser 3
The air-cooling capacity is adjusted to control the condensing pressure HP in the condenser 3 to an appropriate value.

On the other hand, in step S3, the outside air temperature AT becomes +
When the temperature is within the range of 21 ° C to + 27 ° C, the control device 16
Proceeds to step S6 to select the rotation speed according to the low noise characteristic previously obtained by the experiment, and at step S5 the motor 1
2 is output and the motor 12 is operated. Where +21
The outside air temperature AT in the range of 0 ° C to + 27 ° C corresponds to the outside air temperature at night in summer, and the temperature difference is 10 ° C to 15 ° C.
Then, the condensation temperature CT is approximately + 31 ° C to + 42 ° C in the range X
(Fig. 2).

As shown in FIG. 2, the condensing temperature CT is + 40.degree.
The standard rotational speed characteristic is translated so that the ratio becomes 50%. In the standard rotation speed characteristic, the rotation rate N is 75% when the condensing temperature CT is + 40 ° C., and in the rotation speed characteristic that causes low noise, the rotation rate decreases by 25%. Since the noise generated by the condenser blower 11 is reduced due to the decrease in the rotation speed due to this, it is possible to solve the noise problem that occurs when the neighbor's house opens the window and goes to bed at night in summer. In particular, since the rotation speed control of the condenser blower 11 is automatically switched, the operability is improved as compared with, for example, a case where it is manually switched, and only a necessary period (a period corresponding to night in summer) is switched. Therefore, for example, as compared with the case where control is performed with low noise throughout the year, the number of rotations of the condenser blower 11 can be reduced only when necessary, and power consumption is increased due to increase in condensation pressure due to reduction in air cooling capacity. Increasing inconvenience can be suppressed to a minimum.

When the compressor 1 is started, the outside air temperature AT
Is high (for example, + 43 ° C.), the temperature detection of the condenser temperature sensor 14 cannot follow the rise of the condensing pressure HP, and the standard rotation characteristic control shown in FIG.
As shown in, the increase in the rotation speed of the motor 13 of the condenser blower 11 is delayed, and similarly, the condensation pressure HP becomes an abnormally high pressure as indicated by a.

On the contrary, when the outside air temperature AT is extremely low (for example, + 20 ° C.) when the compressor 1 is started and the condensing pressure HP is low (about 8 Kg / cm ² or less), the compressor 1 and the blower for the condenser are at the same time. When 11 is started, the condensation pressure HP cannot be increased as shown in FIG. 4C, and the low pressure LP is immediately decreased accordingly (shown by the broken line in FIG. 6). In such a case, flash gas is generated and the expansion valve 7 is no longer at a normal valve opening. However, since the pressure is below the lower limit of the low pressure switch, the compressor 1 is stopped (CUT).
OUT). After that, when the low pressure LP increases and exceeds the upper limit pressure, the compressor 1 is restarted (CUT I
N), the low pressure LP decreases and the compressor 1 stops again. As a result, the compressor 1 repeats a so-called short cycle operation in which it is operated and stopped at intervals of several seconds or tens of seconds, and the cooling capacity of the air conditioner AC is significantly reduced.

Therefore, in the embodiment, as shown in the flowchart of FIG. 7, when the control device 16 of the speed adjusting device 18 starts the compressor 1 in step S7, the outside air temperature AT is input from the outside air temperature sensor 17 in step S8. . Then, in step S9, the blower 1 for the condenser is drawn from the relationship shown in Table 1.
Number of rotations of the motor 12 (rotation rate N) and the motor 12 of 1
Select the delay time to start.

[0019]

[Table 1]

Then, in step S10, the standard rotation speed characteristic of FIG. That is, specifically, when the outside air temperature AT is a high temperature of, for example, + 43 ° C., the control device 16 indicates from Table 1 that the delay time is 0 s (second),
The rotation rate N of the motor 12 is selected to be 100%, and the motor 12 is operated. As a result, the condenser blower 11 is operated at a rotation rate N of 100% at the same time when the compressor 1 is started, as shown by the solid line (broken line is conventional) in FIG. As a result, the condenser 3 is strongly air-cooled, and an abnormal increase in the condensation pressure HP is suppressed (FIG. 5).

On the contrary, when the outside air temperature AT is extremely low such as 0 ° C., the control device 16 selects the delay time 60 s and the rotation rate N of the motor 12 of 30% from Table 1, and the motor 12 To drive. As a result, the condenser blower 11 is started after a delay of 60 seconds from the start of the compressor 1 as shown by the solid line (broken line is conventional) in FIG. 6, and the rotation rate N is operated at 30%. As a result, the condenser 3 is prevented from being excessively cooled by air, so that the condensing pressure HP is ensured to rise and the low pressure LP is reduced to be reduced, so that the occurrence of the short cycle operation as described above is eliminated. (Fig. 6).

Next, the control device 16 judges in step S11 whether 120 s has elapsed from the start of the compressor 1, and executes the rotation speed control at the start up until the time elapses, and when it has elapsed, in step S12 the standard of FIG. The rotation speed is selected from the target rotation speed characteristic, and the rotation speed is output to the motor 12 in step S13, and thereafter, the above-described control (FIG. 3) is performed.

On the other hand, if the condenser temperature sensor 14 becomes abnormal due to disconnection or the like, it becomes impossible to control the operation of the condenser blower 11 as described above. Therefore, conventionally, regardless of the condensation temperature CT as shown by the broken line in FIG. , For example, the rotation rate N is 60%
The blower 11 for the condensers had to be operated constantly.
In such constant speed control, when the condensation temperature CT changes due to the outside air temperature AT, the condensation pressure HP cannot be maintained at an appropriate value, and the operating efficiency decreases.

Therefore, the control device 16 of the speed adjusting device 18 of the embodiment inputs the condensation temperature CT and the outside air temperature AT by the condenser temperature sensor 14 and the outside air temperature sensor 17 in step S14 of the flowchart of FIG.
At 15, it is judged whether or not the above-mentioned abnormality occurs in the condenser temperature sensor 14, and if not, step S1
The rotation speed is selected in the standard rotation speed characteristic of FIG. 2 in 6 and output to the motor 12 in step S17. If an abnormality occurs, the process proceeds to step S18 and the outside air temperature AT of Table 2 is selected.
The number of rotations (rotation rate N) of the motor 12 is selected according to the characteristics of only the above, and the result is output to the motor 12 in step S17.

[0025]

[Table 2]

That is, specifically, the outside air temperature AT is + 30 ° C.
When the above is high, the rotation rate N of the motor 12 is 100%.
And strongly cool the condenser 3 and, for example, +20
At a temperature of 60 ° C., the rotation rate N is 60%. Further, when the outside air temperature AT is extremely low and is 0 ° C., the control as shown in FIG. 9 for stopping the motor 12 is performed.

As a result, even if the condenser temperature sensor 14 fails, the condenser blower 11 can be controlled at a substantially proper rotational speed based on the outside air temperature AT, and the condenser pressure of the condenser 3 can be controlled. It is possible to maintain the HP at an appropriate value and perform an efficient cooling operation.

Further, when the condenser temperature sensor 14 is disengaged from the pipe 4 or the insulation failure or the attachment failure occurs, the condenser temperature sensor 14 cannot accurately detect the condensation temperature CT. Conventionally, such a defect could not be detected, but the control device 16 of the speed adjusting device 18 according to the embodiment has a configuration shown in FIG.
In step S19 of the flowchart of No. 0, the condensation temperature CT is set by the condenser temperature sensor 14 and the outside air temperature sensor 17.
And the outside air temperature AT are input, and in step S20, the compressor 1
It is determined whether or not the engine is in the normal operation after 2 minutes have elapsed since the engine started, and if not, the process proceeds to step S26 to select the rotation speed of the motor 12 based on the standard rotation speed characteristic of FIG. Output in S25. Then, when 2 minutes have passed from the start of the compressor 1 and the normal operation is performed, the process proceeds to step S21 to calculate a difference (CT-AT) between the condensation temperature CT and the outside air temperature AT, and whether the difference is 5 ° C. or less in step S22. Judge whether or not.

When the difference is 5 ° C. or less, the condenser temperature sensor 14 is hardly affected by the heat from the pipe 4,
In step S23, it is determined that the condenser temperature sensor 14 is disconnected from the pipe 4, and in step S24, the rotation speed (rotation rate N) of the motor 12 is selected according to the characteristics of the outside air temperature AT in Table 2 above, and in step S25. Output to the motor 12. As a result, even when the condenser temperature sensor 14 is abnormally attached, the condenser blower 11 can be controlled at a substantially proper rotational speed based on the outside air temperature AT, and the condensing pressure HP of the condenser 3 can be controlled. It is possible to maintain an appropriate value and perform efficient cooling operation.

Although the air conditioner has been described as an example in the embodiment, the present invention is not limited to such an air conditioner, but the present invention is also effective for refrigeration equipment such as a showcase.

[0031]

As described in detail above, according to the present invention, based on the output of the outside air temperature sensor for detecting the outside air temperature, when the outside air temperature is equivalent to the nighttime in summer, the control device has a standard characteristic. Since the rotation speed of the condenser blower is controlled by the characteristic that it also has low noise, the noise generated by the condenser blower can be suppressed to a low level during the summer night, and when the next house is sleeping with the window open, etc. It is possible to solve the noise problem that occurs in the. In particular, since the rotation speed control of the condenser blower is automatically switched, the operability is improved as compared with, for example, the case where it is manually switched, and the switching is performed only for a necessary period, so that, for example, with the characteristic of low noise throughout the year. The increase in power consumption due to the increase in condensing pressure can be reduced as compared with the case of controlling.

[Brief description of drawings]

FIG. 1 is a refrigerant circuit diagram of a refrigeration cycle of an air conditioner as an embodiment to which the present invention is applied.

FIG. 2 is a diagram showing a rotational speed control characteristic of a condenser blower according to the speed adjusting device of the present invention.

FIG. 3 is a flowchart showing a program of a control device that constitutes the speed adjusting device of the present invention.

FIG. 4 is a diagram showing the relationship between the elapsed time from the start of a conventional compressor and the condensing pressure.

FIG. 5 is a diagram showing the relationship between the elapsed time from the start of the compressor and the condensing pressure when the fan for a condenser is controlled by the speed adjusting device of the embodiment when the outside air temperature is high.

FIG. 6 is a diagram showing the relationship between the elapsed time from the start of the compressor and the condensing pressure when the fan for a condenser is controlled by the speed adjusting device of the embodiment when the outside air temperature is low.

FIG. 7 is a flowchart showing a control program for the condenser blower at the time of starting the compressor by the speed adjusting device of the embodiment.

FIG. 8 is a flow chart showing a control program for the condenser blower when the condenser temperature sensor is abnormal by the speed adjusting apparatus of the embodiment.

FIG. 9 is a diagram illustrating the rotation speed control of the condenser blower based only on the outside air temperature.

FIG. 10 is a flow chart showing a control program of the blower for the condenser when the condenser temperature sensor is not properly attached by the speed adjusting device of the embodiment.

[Explanation of symbols]

 1 Compressor 3 Condenser 7 Expansion valve 8 Evaporator 11 Blower for condenser 12 Motor 14 Condenser temperature sensor 16 Control device 17 Outside air temperature sensor 18 Speed adjustment device

Claims (1)

[Claims] 1. A compressor in which a compressor, a condenser, a decompression device and an evaporator are sequentially connected in an annular fashion to form a refrigeration cycle, and a condenser blower for air-cooling the condenser is provided. A condenser temperature sensor for detecting the temperature of the condenser, a controller for adjusting the number of revolutions of the condenser blower with predetermined standard characteristics based on the output of the condenser temperature sensor, and an outside air temperature for detecting the outside air temperature. A sensor, the control device, based on the output of the outside air temperature sensor, when the outside air temperature corresponds to the nighttime in summer, the rotation speed of the blower for the condenser is lower than the standard characteristic. A speed adjusting device for a blower for a condenser, which is controlled by characteristics.