JPH09250798A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent lowering of a cooling capacity at the time of a cooling overload and to enable suppression of generation of noise even when the speed of rotation of an outdoor blower changes, by operating the outdoor blower at a steady speed of rotation when the temperature of outdoor heat exchange detected at the part on the discharge side of an outdoor heat exchanger is a high set temperature or below and at a high speed of rotation when that temperature exceeds the high set temperature. SOLUTION: A thermistor 16 detecting the temperature of outdoor heat exchange is fitted to an outlet pipe through which a heat exchange medium made a condensate flows, at the portion on the discharge side of a outdoor heat exchanger 6 of an outdoor machine 2. An outdoor blower 15 is made variable in a speed of rotation, operating at a steady speed of rotation or a high speed of rotation. A control means 18 controls the outdoor blower 15 so that it operates at the steady speed of rotation when the temperature of outdoor heat exchange detected by the thermistor 16 is a predetermined high set temperature or below and at the high speed of rotation when that temperature exceeds the high set temperature. An overload state is detected rapidly on the basis of the temperature of outdoor heat exchange, the heat exchange in the outdoor heat exchanger 6 is facilitated and stabilized quickly without lowering a cooling capacity, the number of times of changes in the speed of rotation of the outdoor blower 15 is lessened and thus the possibility of generation of noise is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner, and more particularly to a heat pump type air conditioner constructed by adopting an inverter control system.

[0002]

2. Description of the Related Art Conventionally, in this type of air conditioner, a heat exchange system as shown in simplified form in FIG. 6 has been adopted, and this system uses a heat exchange medium (not shown). It is composed of an outdoor unit 2 and an indoor unit 3 which are communicatively connected via a circulating medium pipe 1. The outdoor unit 2 here has a compressor 4 for compressing the heat exchange medium in a vapor state into high temperature and high pressure, and a four-way valve 5 for switching the flow direction of the heat exchange medium, as shown in the actual structure in FIG. 7.
An outdoor heat exchanger 6 that condenses and liquefies the heat exchange medium, an outdoor blower 7 that cools the outdoor heat exchanger 6, and a decompressor that decompresses the heat exchange medium that is liquefied and supplied to the indoor unit 3 side. 8 and.

Further, the indoor unit 3 at this time is disposed by interposing the medium pipe 1 between the four-way valve 5 constituting the outdoor unit 2 and the decompressor 8 and being installed from the surroundings. The indoor heat exchanger 9 in which the heat exchange medium evaporates while taking heat, and the indoor blower fan 10 are provided, and each of the devices constituting the outdoor unit 2 and the indoor unit 3 is configured. The operation and the order of operations between these devices are to be comprehensively controlled by a control means (not shown) such as a microcomputer. FIG.
The arrow A in the inside indicates the flow direction of the heat exchange medium during cooling.

By the way, when the air conditioner is overloaded with cooling, the heat exchange system is also overloaded, so that the air flows through the discharge pipe 4a connected to the compressor 4 constituting the outdoor unit 2. The temperature of the heat exchange medium discharged to the four-way valve 5 and the outdoor heat exchanger 6 increases, and the cooling capacity decreases. Therefore, in order to prevent such a situation from occurring, in the conventional form, the
As disclosed in Japanese Patent Publication No. 26635, a compressor 4
The thermistor 11 serving as a medium temperature detector is attached to the discharge pipe 4a through which the heat exchange medium discharged from the discharge pipe 4a flows, and when the temperature of the discharge pipe 4a rises above a predetermined set temperature, the control means causes the outdoor The rotation speed of the blower 7 is increased to accelerate the heat exchange in the outdoor heat exchanger 6 to reduce the condensation pressure, and control is performed so as not to reduce the cooling capacity as much as possible.

[0005]

However, in the conventional air conditioner, the thermistor 11 is attached to the discharge pipe 4a connected to the upper side of the compressor 4, which is the discharge side, and is detected through the thermistor 11. Discharge pipe 4
Since the control is performed to increase the rotation speed of the outdoor blower 7 with the temperature rise of a, even if the rotation speed of the outdoor blower 7 is increased, the temperature of the heat exchange medium flowing in the discharge pipe 4a is rapidly increased. However, it is difficult to prevent the cooling capacity from decreasing.

When such a structure is adopted, a large time difference occurs between the change in the number of revolutions of the outdoor blower 7 and the change in the temperature of the heat exchange medium that follows the change in the number of revolutions. Until the temperature of the medium stabilizes, as the temperature of the heat exchange medium changes, the rotation speed of the outdoor blower 7 is repeatedly changed. As a result, noise is frequently generated at the time of changing the rotation speed, which causes discomfort. I was getting tired. Further, the thermistor 11 is connected to the discharge pipe 4a connected to the compressor 4.
Since it is not possible to detect the temperature of the compressor 4 itself, the thermistor or thermostat (not shown) that functions to protect the compressor 4 from overheating is attached.
It was necessary to provide the discharge pipe 4a separately from the thermistor 11.

The present invention was devised in view of these inconveniences, and it is possible to prevent the cooling capacity from deteriorating at the time of cooling overload and to suppress the generation of noise due to the change in the number of rotations of the outdoor blower. The purpose is to provide an air conditioner that can

[0008]

An air conditioner according to claim 1 of the present invention includes an outdoor blower with a variable rotation speed which is operated at a steady rotation speed or a high rotation speed, and a discharge side portion of the outdoor heat exchanger. It has an attached heat exchanger temperature detector, and when the outdoor heat exchanger temperature (heat exchanger temperature) detected through the heat exchanger temperature detector is below a predetermined high set temperature, an outdoor blower is used. It is characterized by comprising a control means for operating at a constant rotation speed and for operating the outdoor blower at a high rotation speed when the outdoor heat exchange temperature exceeds a high set temperature. An air conditioner according to claim 2 of the present invention includes an outdoor blower with a variable rotation speed that is operated at a steady rotation speed or a high rotation speed,
While having a heat exchange temperature detector attached to the discharge side portion of the outdoor heat exchanger, when the outdoor heat exchange temperature detected through the heat exchange temperature detector exceeds a predetermined high set temperature, A control means for operating the outdoor blower at a high rotation speed from the start of operation until a predetermined set time has elapsed and for operating the outdoor blower at a constant rotation speed after the set time has elapsed Is characterized by.

An air conditioner according to a third aspect of the present invention includes an outdoor blower with a variable rotation speed that is operated at a steady rotation speed or a low rotation speed, and a heat attached to a discharge side portion of the outdoor heat exchanger. With the heat exchanger temperature detector, when the outdoor heat exchanger temperature detected through the heat exchanger temperature detector exceeds a predetermined low set temperature, the outdoor blower is operated at a constant rotation speed, and When the outdoor heat exchange temperature is equal to or lower than the low preset temperature, the outdoor blower is provided with a control means for operating at a low rotation speed. Furthermore, in the air conditioner according to claim 4 of the present invention, a compressor temperature detector for detecting the temperature of the compressor itself is attached to an upper portion of the compressor to which the discharge pipe is connected. It has a feature.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory view showing a simplified heat exchange system for an air conditioner according to this embodiment, FIG. 2 is an explanatory view showing the actual structure of an outdoor unit 2, and FIGS. 1
6 is a flowchart showing an operation sequence of the air conditioner according to the embodiment and the modification example thereof. Since the basic configuration of this air conditioner does not differ from the conventional configuration, the same components as those in FIGS. 6 and 7 showing the conventional configuration in FIGS. 1 and 2 are designated by the same reference numerals.

The heat exchange system for an air conditioner according to the first embodiment, as shown in FIG. 1, has an outdoor unit 2 and an indoor unit which are connected to each other via a medium pipe 1 through which a heat exchange medium flows. The outdoor unit 2 includes a compressor 4 and a compressor 4 as shown in FIG.
The four-way valve 5, the outdoor heat exchanger 6, the pressure reducer 8, and the outdoor blower 15 are provided. Then, for the discharge side portion of the outdoor heat exchanger 6 that constitutes the outdoor unit 2 here, that is, for the outlet pipe 6a through which the liquefied heat exchange medium condensed by the outdoor heat exchanger 6 flows, A thermistor 16 functioning as a heat exchange temperature detector for detecting the temperature is attached, and the outdoor blower 15 at this time has a steady rotation speed or a rotation speed that is operated at a high rotation speed higher than the steady rotation speed. It has a variable configuration.

At this time, the thermistor 1 as a medium temperature detector is connected to the discharge pipe 4a connected to the compressor 4.
1 is not attached, and a compressor temperature detector that functions as an overheat protection for the compressor 4 by detecting the temperature of the compressor 4 itself at the upper portion of the compressor 4 to which the discharge pipe 4a is connected. Is attached to the thermistor 17. On the other hand, the indoor unit 3 that constitutes the air conditioner by being connected to the outdoor unit 2 via the medium pipe 1 is configured to include the indoor heat exchanger 9 and the indoor blower fan 10. The indoor heat exchanger 9 in which the heat exchange medium evaporates is disposed between the four-way valve 5 and the pressure reducer 8 that form the outdoor unit 2. The arrow A in FIG. 1 indicates the flow direction of the heat exchange medium during cooling.

Further, this air conditioner is provided with a control means (not shown) consisting of a microcomputer, and depending on this control means, each device constituting the outdoor unit 2 and the indoor unit 3 is controlled. The operation and the operation sequence between these devices are generally controlled. Then, for the control means included in the air conditioner according to the present embodiment, the outdoor heat exchange temperature detected through the thermistor 16 attached to the outlet pipe 6a, which is the discharge side portion of the outdoor heat exchanger 6, that is, When the outdoor heat exchange temperature, which changes in accordance with the outdoor air temperature, is equal to or lower than a predetermined high preset temperature T1 which is set in advance, the outdoor blower 15 is operated at a constant rotation speed, and the outdoor heat exchange temperature is When the temperature exceeds the high set temperature T1, the control means 18 having a function of operating the outdoor blower 15 at a high rotation speed is incorporated.

When the air conditioner is overloaded with cooling, the heat exchange system is overloaded, so the temperature of the heat exchange medium discharged from the compressor 4 constituting the outdoor unit 2 through the discharge pipe 4a rises. At the same time, the temperature of the heat exchange medium discharged from the outdoor heat exchanger 6 through the outlet pipe 6a toward the pressure reducer 8 rises. However, in the air conditioner according to the present embodiment, the temperature rise of the heat exchange medium is detected by the thermistor 16 attached to the outlet pipe 6a, and the outdoor heat exchange temperature detected through the thermistor 16 becomes the outside air temperature. Because it changes following,
The fact that the outdoor heat exchange temperature exceeds the preset high set temperature T1 can reach the overload state more quickly than in the conventional case.

Therefore, as shown in the flow chart of FIG. 3, when the outdoor heat exchange temperature exceeds the high set temperature T1, the outdoor heat exchanger 6 performs heat exchange while operating the outdoor blower 15 at a high rotation speed. By the control means 18, the condensing pressure is lowered to control the cooling capacity so as not to be deteriorated and is stabilized at an early stage.
And at this time, when the number of revolutions of the outdoor blower 15 changes,
The time difference with the temperature change of the heat exchange medium that follows this change in the rotation speed is reduced, and the number of changes in the rotation speed of the outdoor blower 15 can be small, so that the chance of noise generation is reduced. The outdoor heat exchange temperature detected by the thermistor 16 due to the elimination of the overload state is the high set temperature T1.
In the case of the following, the control means 18 controls the outdoor blower 15 to operate at a constant rotation speed.

Furthermore, in the air conditioner according to the first embodiment, the outdoor heat exchange temperature is determined based on either the cooling load at the start of the cooling operation or the outside air temperature being high. Since the temperature exceeds the high set temperature T1, it is possible to execute the control utilizing this, that is, the control as in the modified example described below. That is, in the air conditioner according to this modification, when the outdoor heat exchange temperature detected by the thermistor 16 exceeds the high set temperature T1, the outdoor blower 15 continues until a predetermined set time elapses from the start of operation. Is operated at a high rotational speed, and after the set time has elapsed, the control means 18 has a function of operating the outdoor blower 15 at a constant rotational speed.
It is done in advance.

If the control means is also provided with such a function, as shown in the flow chart of FIG. 4, when the outdoor heat exchange temperature exceeds the high set temperature T1, a predetermined setting is made from the start of the operation. Outdoor blower 15 until time passes
By increasing the cooling capacity by operating at a high rotation speed, the indoor temperature is brought close to the required set temperature in a short time, while after the set time has elapsed,
The outdoor blower 15 is operated at a steady rotation speed to maintain the cooling capacity, which is an advantage in practical use. Here, the outdoor heat exchange temperature is the high set temperature T1.
In the following cases, the outdoor blower 15 is operated at the steady rotation speed.

Next, a second embodiment according to the present invention will be described with reference to FIGS. 1 and 2 which are the same as the first embodiment, and FIG. 5 which is a flow chart showing the operation sequence of the air conditioner in this embodiment. It will be explained based on. The overall configuration of the air conditioner according to the second embodiment is basically the same as that of the first embodiment, and detailed description thereof is omitted here.

The heat exchange system for an air conditioner according to the second embodiment, as shown in FIG. 1, includes an outdoor unit 2 and an indoor unit 3 which are connected to each other through a medium pipe 1 through which a heat exchange medium flows. The outdoor unit 2 is composed of a compressor 4, a four-way valve 5, an outdoor heat exchanger 6, a decompressor 8, and an outdoor blower 15, as shown in the actual structure of FIG. ing. The outdoor heat exchanger 6 that constitutes the outdoor unit 2
A thermistor 16 as a heat exchange temperature detector for detecting the outdoor heat exchange temperature is attached to the outlet pipe 6a which is the discharge side portion of the outdoor blower 15 at the steady rotation speed. Alternatively, it has a variable rotational speed configuration that is operated at a high rotational speed lower than the steady rotational speed.

Further, at this time, a thermistor 17 for detecting the temperature of the compressor 4 itself is attached to the upper portion of the compressor 4 to which the discharge pipe 4a is connected.
Reference numeral 7 serves to protect the compressor 4 from overheating. Further, the air conditioner according to this embodiment has a control means including a microcomputer for integrally controlling the operation of each device constituting the outdoor unit 2 and the indoor unit 3 and the operation sequence between these devices (Fig. (Not shown). Then, for this control means, the outdoor heat exchange temperature detected through the thermistor 16 attached to the outlet pipe 6a, which is the discharge side portion of the outdoor heat exchanger 6, is set to a predetermined low preset temperature T2. When it exceeds, the outdoor blower 15 is operated at a constant rotation speed, and
When the outdoor heat exchange temperature is lower than or equal to the low set temperature T2, the control means 1 for operating the outdoor blower 15 at a low rotation speed.
8 are incorporated.

By the way, when the outdoor heat exchange temperature detected by the thermistor 16 is lower than the low set temperature T2, the condensing pressure of the outdoor heat exchanger 6 can be small. Therefore, depending on the control means 18 included in this air conditioner,
As shown in the flowchart of FIG. 5, when the outdoor heat exchange temperature exceeds the low set temperature T2, the outdoor blower 15 is operated at a constant rotation speed, and the outdoor heat exchange temperature becomes the low set temperature T2 or lower. As a result, the outdoor blower 15 is controlled to operate at a low rotation speed while
By operating the outdoor blower 15 at a low rotation speed, it is possible to suppress the generation of noise in the outdoor unit 2 while ensuring the cooling capacity and reduce the required power.

[0023]

As described above, according to the first aspect of the present invention.
According to this air conditioner, when the outdoor heat exchange temperature detected through the heat exchange temperature detector attached to the discharge side portion of the outdoor heat exchanger exceeds the high set temperature, the outdoor blower is operated at a high rotation speed. Since it is operated with the air blower, it is possible to accelerate the heat exchange in the outdoor heat exchanger while operating the outdoor blower at a high rotation speed, and reduce the condensing pressure to prevent the cooling capacity from decreasing while cooling. The effect that the overload state can be eliminated at an early stage is obtained.
Then, in this case, since the time difference between the rotation speed change of the outdoor blower and the temperature change of the heat exchange medium following this rotation speed change becomes small, the rotation speed change count of the outdoor blower is small, and As a result of reducing the chances of noise generation, it is possible to prevent frequent noise generation and prevent discomfort.

Further, according to the air conditioner of the second aspect of the present invention, when the outdoor heat exchange temperature exceeds the high set temperature, the outdoor blower is operated until a predetermined set time elapses from the start of operation. After operating at a high rotation speed and after the set time has elapsed, the outdoor blower is operated at a steady rotation speed. It is possible to get closer.

Further, according to the air conditioner of the third aspect of the present invention, when the outdoor heat exchange temperature detected by the heat exchange temperature detector is lower than the low set temperature, the outdoor blower has a low rotation speed. Since the operation is performed with this, it is possible to suppress the generation of noise in the outdoor unit while ensuring the cooling capacity with the operation of the outdoor blower at a low rotation speed, and to reduce the required power. Further, according to the air conditioner of claim 4 of the present invention, since the compressor temperature detector is attached to the upper side portion of the compressor to which the discharge pipe is connected, the temperature of the compressor itself can be quickly increased. It becomes possible to detect, and the effect that the overheat protection of the compressor can be realized is obtained.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a simplified heat exchange system of an air conditioner according to the present embodiment.

FIG. 2 is an explanatory diagram showing a substantive structure of an outdoor unit that constitutes an air conditioner.

FIG. 3 is a flowchart showing an operation sequence of the air conditioner according to the first embodiment.

FIG. 4 is a flowchart showing an operation sequence of an air conditioner according to a modified example.

FIG. 5 is a flowchart showing an operation sequence of the air conditioner according to the second embodiment.

FIG. 6 is an explanatory view showing a simplified heat exchange system of an air conditioner according to a conventional form.

FIG. 7 is an explanatory diagram showing a substantive structure of an outdoor unit that constitutes the air conditioner.

[Explanation of symbols]

 15 Outdoor blower 16 Thermistor (heat exchanger temperature detector) 18 Control means T1 high set temperature T2 low set temperature

Claims (4)

[Claims] 1. An outdoor blower with a variable rotation speed, which is operated at a steady rotation speed or a high rotation speed, and a heat exchange temperature detector attached to a discharge side portion of the outdoor heat exchanger, When the outdoor heat exchange temperature detected by the exchange temperature detector is below the predetermined high set temperature, the outdoor blower is operated at a constant rotation speed, and the outdoor heat exchange temperature exceeds the high set temperature. An air conditioner characterized by comprising control means for operating the outdoor blower at a high rotational speed. 2. An outdoor blower having a variable rotation speed, which is operated at a steady rotation speed or a high rotation speed, and a heat exchange temperature detector attached to a discharge side portion of the outdoor heat exchanger, When the outdoor heat exchange temperature detected by the exchange temperature detector exceeds a predetermined high set temperature, the outdoor blower is operated at a high rotation speed until a predetermined set time elapses from the start of operation, and An air conditioner comprising control means for operating the outdoor blower at a constant rotation speed after a set time has elapsed. 3. An outdoor blower with a variable rotation speed, which is operated at a steady rotation speed or a low rotation speed, and a heat exchange temperature detector attached to a discharge side portion of the outdoor heat exchanger, When the outdoor heat exchange temperature detected by the exchange temperature detector exceeds a predetermined low set temperature, the outdoor blower is operated at a constant rotation speed, and the outdoor heat exchange temperature is below the low set temperature. An air conditioner characterized by comprising control means for operating the outdoor blower at a low rotation speed. 4. A compressor temperature detector for detecting the temperature of the compressor itself is attached to an upper portion of the compressor to which the discharge pipe is connected. The air conditioner according to any one of 1.