JPS62415B2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an air conditioner.

Conventionally, as an air conditioner using a refrigeration cycle, there has been a so-called separate type air conditioner in which an indoor unit and an outdoor unit are connected by piping. As a control method for this air conditioner, for example, when starting cooling operation, the compressor starts up in conjunction with the operation of the cooling operation switch, and at the same time the fans of the indoor and outdoor units start to start cooling. The commonly used method is to repeatedly start and stop the compressor and outdoor fan depending on the action of the indoor temperature controller.

However, when cooling is started and the compressor is restarted, the outdoor heat exchanger housed in the outdoor unit has a temperature higher than that of the surrounding outside air due to radiant heat received from the box of the outdoor unit or the sun, and geothermal heat received from the ground. The reality is that it is overheated.

However, if the outdoor fan was started at the same time as the compressor was started under these conditions, the refrigerant that had been superheated under the above conditions would be
Since the air passes through a pressure reducer, the temperature drop in the evaporator inside the indoor unit is delayed accordingly.

As a result, while there is a slight time delay after startup until it produces steady cooling capacity, the compressor consumes the same electrical input as in steady state with almost no delay after startup, so consider the entire cooling period of one year. Starting the compressor while the outdoor heat exchanger remains overheated is one of the major reasons for reducing cooling efficiency. Therefore, as an air conditioner that can solve the above-mentioned problem and improve the startup characteristics of the cooling capacity by removing the overheating of the outdoor heat exchanger before starting the compressor, the air conditioner is shown in Figures 1 to 4. suggested something. That is, as shown in FIG. 1, this air conditioner includes an indoor unit 3 having an indoor heat exchanger 1 and an indoor fan 2, a compressor 4, an outdoor heat exchanger 5,
Outdoor unit 8 having a pressure reducer 6 and an outdoor fan 7
As shown in FIG. 2, these are separately arranged indoors 9 and outdoors, and these are connected by piping 10, compressor 4, outdoor heat exchanger 5, pressure reducer 6, and indoor heat exchanger 1. This is a separate type cooling system that constitutes a refrigeration cycle system connected in the order shown in FIG. It has a temperature control switch 15 that operates on and off in response to a detection signal from a temperature detector 14, and an outdoor fan drive motor 16 connected in series to the temperature control switch 15, and connected in parallel to the indoor fan drive motor 13. The outdoor fan is driven by an outdoor heat exchanger precooling circuit 17, a delay switch 18 that turns on a predetermined time later than the temperature control switch 15, and a compressor drive motor 19 connected in series to the delay switch 18. Compressor drive circuit 20 connected in parallel to motor 16
It is composed of

The operation of this air conditioner will be explained next.

First, when the start switch 12 is turned on, the indoor
The indoor temperature sensor 14 detects the high temperature of the room, and the temperature control switch 15 is closed based on the detection signal.
The outdoor fan drive motor 16 is started at the same time as the indoor fan drive motor 13, and the outdoor heat exchanger 5 is immediately cooled by the outdoor fan 7 after starting. After that (within several tens of seconds), the delay switch 18 is closed, the compressor drive motor 19 is started, the compressor 4 starts operating, and the cooling of the room 9 starts. At this time, since the superheat of the outdoor heat exchanger 5 has already been removed, the temperature of the indoor heat exchanger 1 is also rapidly lowered, and the room 9 is rapidly cooled.

Figure 4A compares the above operation with the conventional example.
Shown in D. In the figure, the horizontal axis is the elapsed time t after the start of operation, while the vertical axis in figure A is the cooling capacity Q during a transient period, the vertical axis in figures B and C is the compressor electrical input W, and the vertical axis in figure D is The vertical axis of is shown as the temperature T in the room 9. In addition, in this figure, the start-up delay time of compressor 4 is much shorter than other operating times, so
This is ignored. In the figure, the solid line shows the operation results of this proposed example, and the broken line shows the results of the conventional control circuit. As is clear from the figure,
In this proposed example, the rise in the cooling capacity Q is rapid compared to the conventional one, so the room temperature T also falls quickly, and the set value
The time to reach T ₁ is also quick.

Similarly, when the temperature control switch 15 repeatedly stops driving the compressor 4 based on the detection signal from the indoor temperature detector 14, the outdoor fan drive motor 16 starts first, and then the compressor drive motor 19 starts. As shown in FIG. 4, since the cooling capacity Q rises quickly at the time of restart, the restart operation time is shorter than before.

With this configuration, at the start of operation and when the compressor 4 is restarted, the outdoor fan 16 starts operating in advance, and after a slight delay, the compressor 4 starts up, and the cooling capacity builds up quickly, rapidly reducing the room temperature. reaches the set temperature, and when compared over a one-year cooling period, it consumes less electricity than before.

However, this proposed example had the following problems.
That is, in the proposed example, after the outdoor fan drive motor 16 is driven at the set temperature, the compressor drive motor 19 is
Since the system is configured to drive the system, there is no problem when it is stopped, but there is a startup delay when it is started up, and when the temperature changes rapidly, cooling will be resumed after the temperature has risen considerably above the set temperature. There is a problem in that this startup delay occurs each time the device is restarted by repeatedly stopping and restarting due to temperature control, which increases discomfort.

Further, in the proposed example, a delay switch 18 is used to set the startup delay time of the compressor drive motor 19. For this reason, there is a problem that the delay time is determined regardless of the size of the cooling load due to the size of the room, etc., and if the cooling load changes, an appropriate delay time cannot be obtained.

Furthermore, the proposed example has the following problems. That is, in this type of air conditioner using a refrigeration cycle, after the compressor drive motor 19 stops, warm refrigerant flows into the indoor heat exchanger 1, and the condensed water that has formed in the indoor heat exchanger 1 during cooling is transferred to the warm refrigerant. It evaporates. In the proposed example, this evaporation continues until the air conditioner is restarted, causing a problem in that it increases the indoor temperature.

In addition, as a conventional example with a configuration similar to this proposed example, there is a system in which the compressor is started later than the outdoor fan in order to balance the pressure at the time of starting the compressor (see Utility Model Application No. 53-39054). ). but,
This conventional example also has the same problems as the above-mentioned proposed example.

The purpose of this invention is to eliminate the overheating of the outdoor heat exchanger before restarting the compressor and improve the startup characteristics at restart, thereby eliminating the delay in restarting the cooling operation and achieving comfortable indoor temperature control. Furthermore, it is an object of the present invention to provide an air conditioner that can reduce evaporation of condensed water when stopped.

An embodiment of this invention will be described based on FIG. 5. This air conditioner detects an arbitrarily set restart temperature T ₁ (see Figure 4) using an indoor temperature sensor 14.
a temperature control switch 21 that drives the compressor drive motor 19 when the restart temperature T ₁ is detected;
The device is equipped with a preceding controller 22 that detects a preceding temperature that is a predetermined temperature (for example, 1° C.) lower than that of the outdoor fan drive motor 16 and drives the outdoor fan drive motor 16. Note that the same parts as those in the proposed example shown in FIGS. 1 to 4 are given the same reference numerals, and the explanation thereof will be omitted. To explain only the outline again, this air conditioner also includes the compressor 4 in FIG.
A refrigeration cycle system that sequentially connects an outdoor heat exchanger 5, a pressure reducer 6, and an indoor heat exchanger 1, an outdoor fan 7 for the outdoor heat exchanger 5, and an indoor fan 2 for the indoor heat exchanger 1; A compressor drive motor 19 that drives the compressor 4, an outdoor fan drive motor 16 that drives the outdoor fan 7, and an indoor fan 2.
The indoor fan drive motor 13 drives the indoor fan.

The advance controller 22 is set to turn off at the stop temperature T ₂ (see FIG. 4), and this off operation causes both the outdoor fan drive motor 16 and the compressor drive motor 19 to stop. Advance controller 2
It is desirable that the temperature control switch 2 and the temperature control switch 21 are capable of setting the preceding temperature and setting the restart temperature _T1 in conjunction with each other. In addition, the temperature control switch 21
A series circuit between the controller 22 and the compressor drive motor 19 may be connected in parallel with a series circuit between the preceding controller 22 and the outdoor fan drive motor 16. In that case, the temperature control switch 21 is one that turns off at the stop temperature _T2 .

According to the air conditioner having this configuration, when repeatedly stopping and restarting the cooling operation, the outdoor fan drive motor 16 is driven in advance at the preceding temperature, and the compressor drive motor 19 is immediately driven at the set restart temperature _T1 .
Since the cooling operation is restarted by driving the outdoor heat exchanger 5, the overheating of the outdoor heat exchanger 5 is removed before the compressor is driven, improving the startup characteristics, eliminating the delay in restarting the cooling operation, and achieving comfortable indoor temperature control. I can figure it out. The above-mentioned overheating of the outdoor heat exchanger 5 refers to the overheating that occurs from the time when the outdoor heat exchanger 5 stops at the stop temperature _T2 until the cooling operation starts again.

Furthermore, according to this configuration, the preceding controller 22 detects a preceding temperature that is a predetermined temperature lower than the restart temperature T ₁ and drives the outdoor fan drive motor 16, so that the delay element is used as in the proposed example and the conventional example. Compared to the case where the delay time is set in terms of time, this method has the advantage that it is easier to obtain an appropriate advance drive time even when the cooling load changes, such as the size of the room.

Further, in this configuration, since the outdoor fan drive motor 16 is driven in advance, the time during which the outdoor fan 7 is stopped during cooling by repeatedly stopping and driving is shorter than that of the proposed example. Therefore, the time for the warm refrigerant to flow into the indoor heat exchanger 1 and evaporate the condensed water after the compressor 4 is stopped is correspondingly shortened, and the increase in indoor humidity is alleviated.

As described above, the air conditioner of the present invention includes a temperature control switch that drives the compressor when an arbitrarily set restart temperature is detected by an indoor temperature detector, and a temperature control switch that is lower than the restart temperature by a predetermined temperature. Since it is equipped with an advance controller that detects the advance temperature and drives the outdoor fan, the following effects can be obtained. In other words, since the outdoor fan is driven in advance and the compressor is immediately driven at the set restart temperature to restart cooling operation, the overheating of the outdoor heat exchanger is removed before the compressor is driven, improving the startup characteristics. This eliminates the delay in restarting cooling operation and provides comfortable indoor temperature control. In addition, since the preceding controller detects a preceding temperature that is a predetermined temperature lower than the restart temperature and drives the outdoor fan, compared to setting a delay time using a delay element, cooling loads such as the size of the room, etc. It is easy to obtain an appropriate pre-driving time even with changes in . Furthermore, since the outdoor fan is driven in advance, the time during which the outdoor fan is stopped during cooling by repeatedly stopping and driving is shorter than in the conventional example. Therefore, the time for the warm refrigerant to flow into the indoor heat exchanger and evaporate the condensed water after the compressor is stopped is correspondingly shortened, which has the effect of alleviating the increase in indoor temperature.

[Brief explanation of the drawing]

Fig. 1 is a schematic system diagram of a separate air conditioner to which the proposed example is applied, Fig. 2 is a schematic diagram showing an example of its arrangement, Fig. 3 is a circuit diagram showing a proposed example of an air conditioner, and Fig. 4 is a schematic diagram showing an example of its arrangement. FIG. 5 is a circuit diagram showing an embodiment of the present invention. 1...Indoor heat exchanger, 2...Indoor fan, 3...
...Indoor unit, 4...Compressor, 5...Outdoor heat exchanger, 6...Pressure reducer, 7...Outdoor fan, 8...
Outdoor unit, 9... Indoor, 10... Piping, 11
...Power source, 12...Start switch, 13...Indoor fan drive motor, 14...Indoor temperature detector, 16
... Outdoor fan drive motor, 19 ... Compressor drive motor, 21 ... Temperature control switch, 22 ... Advance controller.

Claims (1)

[Claims] 1 A refrigeration cycle system that sequentially connects a compressor, an outdoor heat exchanger, a pressure reducer, and an indoor heat exchanger, an outdoor fan for the outdoor heat exchanger, an indoor fan for the indoor heat exchanger, and drives the compressor. a compressor drive motor that drives the outdoor fan; an indoor fan drive motor that drives the indoor fan; An air conditioner comprising: a temperature control switch that drives a compressor; and a preceding controller that detects a preceding temperature that is a predetermined temperature lower than the restart temperature and drives the outdoor fan.