JPH0828934A - Air conditioner - Google Patents

Abstract

PURPOSE:To obtain an air conditioner in which an indoor blower can be effectively and safely started at the time of starting heating and the discomfort in cold air diffusion at the time of starting heating is prevented despite a low cost-structure. CONSTITUTION:A heating cycle has a temperature sensor 11 for detecting a refrigerant temperature condensed by an indoor heat exchanger 3 or a pressure sensor (switch) 12 for detecting a refrigerant pressure. Thus, a gear shifting function is abolished in an indoor blower 6. The sensors 11, 12 can be effectively utilized in a cooling cycle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner which uses a heat pump to perform a heating operation, and is effective for eliminating the feeling of cool air at the start of operation without a speed change mode of a blower.

[0002]

2. Description of the Related Art In a conventional air conditioner, when a heating operation is started in a refrigerating cycle as shown in FIG. 1, a signal from a blown air temperature sensor 8 is supplied to a room in order to prevent the blower air from feeling cold when it is blown. By taking in the blower control device 10 and starting the indoor blower 6 in the breeze mode, the feeling of cold wind is softened.

Another conventional air conditioner is disclosed in
As described in Japanese Patent No. 61-55542, the signal of the indoor heat exchanger temperature sensor 9 is taken into the indoor blower control device 10, the indoor blower 6 is started by the temperature rise of the condenser 3, and the air volume is gradually raised to the set air volume. This prevents the feeling of cold wind.

[0004]

In one air conditioner in the prior art, since the blower air temperature is detected and the indoor blower is controlled, the blower mode must be used to detect the blower air temperature, for example, start by a breeze. Is necessary and the feeling of cold wind is inevitable. Also, the blower control device 1
2 and the motor for the blower are provided with a speed change function, which is complicated and expensive.

Further, in another air conditioner in the prior art, since the temperature of the indoor heat exchanger is detected and the indoor blower is controlled, the influence of disturbance due to the humidity of the intake air, for example,
Since the water condensing temperature due to heating and humidification is easily received, the temperature sensor is erroneously detected and the start-up delay of the indoor blower occurs due to the delay of the followability, which increases the high pressure of the compressor 1 and protects the air conditioner. The device may operate and stop abnormally. Further, even in this air conditioner, it is necessary to gradually increase the air volume after starting the blower. This is because a rapid increase in the air volume causes a rapid decrease in the temperature of the indoor heat exchanger, which causes repeated stop / operation of the indoor blower.

It is an object of the present invention to provide an air conditioner which prevents a feeling of cool air at the time of starting heating and has an inexpensive structure because the indoor blower does not have a speed changing function.

[0007]

In order to solve the above problems, the air conditioner of the present invention is characterized by detecting the temperature of the refrigerant condensed in the indoor heat exchanger and controlling the indoor blower. Further, the control means may detect the pressure of the refrigerant condensed in the indoor heat exchanger. Also, by using both together, it is possible to start the indoor blower with better controllability and safety,
Moreover, with an inexpensive structure in which the indoor blower does not have a speed change function,
It is possible to prevent the feeling of cold wind when starting heating.

[0008]

By detecting the refrigerant temperature of the indoor heat exchanger and starting the indoor blower, it is possible to prevent cold air from being blown out until the indoor heat exchanger is warmed up after the compressor is started at the time of heating operation start. Since this control means detects the temperature of the refrigerant condensed in the indoor heat exchanger, the blowing mode (for example, a breeze) at the time of starting is unnecessary. In addition, it is not easily affected by external disturbances such as sucked air, has no false detection of temperature, and has excellent followability.

If the condensing pressure is detected as an alternative to the control means, the response is further improved, and the same effect can be obtained. Further, this also makes it possible to avoid the operation of the high-pressure pressure cutoff device, which is a protection device for the air conditioner, which is caused by a delay in starting the indoor blower.

[0010]

EXAMPLE In the heat pump type air conditioner of the example shown in FIG. 2, in the heating cycle, the refrigerant is compressed into high temperature and high pressure by the compressor 1, sent to the indoor heat exchanger 3 by the four-way valve 2, and the indoor blower 6 Is condensed by the air sent by to become a liquid refrigerant, and this liquid refrigerant is expanded by the expansion valve 4, then sent to the outdoor heat exchanger 5, evaporated by the air sent by the outdoor blower 7, and becomes a gas refrigerant, It is sucked into the compressor 1 via the four-way valve 2. In this way, the indoor air is heated and provided for heating when the refrigerant is condensed.

On the other hand, in the cooling cycle, the four-way valve 2 switches the flow path, so that the heat exchanger for condensing the refrigerant and the heat exchanger for evaporating are exchanged indoors and outdoors. Thus, the room air is cooled and provided for cooling when the refrigerant evaporates.

In order to prevent a feeling of cool air at the time of starting the heating cycle in the air conditioners constituting these refrigeration cycles, the indoor heat exchanger temperature sensor 8 or the indoor heat exchanger temperature sensor 9 is replaced in place of the indoor heat exchanger. The indoor heat exchanger refrigerant temperature sensor 11 for detecting the temperature of the liquid refrigerant condensed in 3 is provided. The temperature thus detected is taken into the indoor blower control device 10, and when the temperature reaches a certain temperature, the indoor blower 6 is started. According to the present invention, the indoor blower 6 does not detect the temperature of blown air, so it is simply turned off.
It can be started on, and gear shifting (for example, a breeze) is unnecessary.
Further, since the temperature of the heat exchanger itself is not detected, it is unlikely to be affected by the suction air flowing into the indoor heat exchanger, and reliable starting can be performed. Further, this indoor heat exchanger refrigerant temperature sensor 11
In the cooling cycle, can also be used as means for controlling the indoor blower 6 or the compressor 1 or the expansion valve 4 to prevent freezing of the indoor heat exchanger 3.

In order to carry out the above embodiment more reliably, the condensing pressure sensor 12 for detecting the pressure of the liquid refrigerant condensed in the indoor heat exchanger 3 may be used. The condensing pressure detected by this is converted into the condensing temperature by the indoor blower control device 10 to obtain the same effect, and more reliable starting can be performed. In the cooling cycle, the condensing pressure sensor 12 can also be used as a means for controlling the outdoor blower 7 or the compressor 1 or the expansion valve 4 when the condensing pressure is abnormally decreased or increased due to the influence of the outdoor air temperature or the like.

As described above, there is also a method of using the indoor heat exchanger refrigerant temperature sensor 11 and the condensing pressure sensor 12 together, which is an effective means for constructing a cooling cycle. According to the present embodiment, the indoor blower 6 is started at the time of heating by the indoor heat exchanger refrigerant temperature sensor 11 to prevent a temperature detection deviation,
The condensing pressure sensor 12 is used as protection due to tracking delay. This is because it is possible to avoid the operation of the high pressure cutoff device 13, which is a protection device of the air conditioner, by detecting an abnormal increase in high pressure due to a delay in the start of the indoor blower 6 and starting the indoor blower 6. Become. This condensing pressure sensor 12
Is a pressure SW that simply detects pressure and turns on and off, and is a cost effective and safe starting means.

[0015]

As described above, according to the present invention, it is possible to prevent a feeling of cold wind at the time of starting the heating of the heat pump type air conditioner and perform a reliable and safe starting. Further, the speed change function is not required for the indoor blower, and the cost can be reduced by using the tool as the refrigeration cycle control means during cooling.

[Brief description of drawings]

FIG. 1 is a system diagram of a conventional refrigeration cycle.

FIG. 2 is a system diagram of a refrigeration cycle according to an embodiment of the present invention.

[Explanation of symbols]

11 ... Indoor heat exchanger refrigerant temperature sensor, 12 ... Condensing pressure sensor, 13 ... High-pressure pressure cutoff device.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yutaka Yushita 390 Muramatsu, Shimizu City, Shizuoka Prefecture, Hitachi Air Conditioning Systems Division (72) Inventor Hiromi Kawaguchi 390 Muramatsu, Shimizu City, Hitachi Hitachi Shimizu Engineering Co., Ltd. In the company

Claims (1)

[Claims] 1. An air conditioner having a compressor, a condenser, an expansion valve, an evaporator, and a blower for exchanging heat with each of the condenser and the evaporator, and an indoor blower operation when an operation mode is a heating operation. An air conditioner that has a shift function at the start and is controlled without giving a feeling of cold wind.