JPH0428959A - Air conditioner - Google Patents

Abstract

PURPOSE:To provide a safe air conditioner not influencing badly against electrical parts such as inverter device or the like even if an outdoor air blower is stopped during a cooling operation by a method wherein a temperature of an outdoor heat exchanger is detected by a temperature sensor and an operation of a compressor is stopped when a result of sensing exceeds a reference value set in advance in a micro-computer. CONSTITUTION:A temperature characteristic of an outdoor heat exchanger 3 corresponding to an operating frequency of a compressor is stored in a micro-computer. During a cooling operation, this temperature characteristic and a temperature detected by a temperature sensor 6 are repeatedly compared and judge every time a predetermined period is attained. When the temperature of an outdoor heat exchanger 3 is in a stopping range, it is judged that an outdoor air blower 7 is stopped, an output of a control signal for an inverter device 11 is eliminated and then an operation of the compressor 1 is controlled to be stopped. In this way, the temperature of the outdoor heat exchanger is detected and compared with a reference value set in advance in the micro-computer, thereby it is possible to judge that the operation of the outdoor air blower is stopped, the control signal for the inverter device is eliminated in response to the result of judgement and further to stop the operation of the compressor.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an air conditioner, and more particularly, to a control means when an outdoor blower disposed on an outdoor unit side abnormally stops.

[Conventional technology]

The outdoor unit side of the air conditioner includes a compressor, an inverter device that controls the rotation speed of the compressor, an outdoor heat exchanger, and a temperature detection sensor that detects the temperature of the outdoor heat exchanger.
An outdoor blower, etc. that air-cools the outdoor heat exchanger, etc. is installed at a predetermined position, and the inverter device is controlled by a control signal sent from a microcomputer installed on the indoor unit. The rotation speed of the compressor is controlled by the inverter device, and the outdoor heat exchanger and the like are air-cooled as the outdoor blower operates.

[Problem to be solved by the invention]

By the way, in the outdoor unit of the air conditioner configured as described above, if the outdoor blower stops due to an abnormality in the control circuit or blower motor during cooling operation, not only the outdoor heat exchanger but also the inverter device will stop air cooling. As a result, the temperature of the electrical components constituting the inverter device may exceed the maximum rated value due to self-heating and an increase in ambient temperature.

If the temperature exceeds the maximum rated value for a long period of time, it may shorten the life of electrical components or cause them to malfunction, but no particular countermeasures have been taken in the past to deal with such problems.

Therefore, in the present invention, it is an object of the present invention to solve these problems and provide a safe air conditioner that does not adversely affect electrical components such as an inverter device even if the outdoor blower stops during cooling operation. The purpose is

[Means to solve the problem]

The present invention was made to solve the above problems, and includes a compressor, an inverter device for controlling the rotation speed of the compressor, an outdoor heat exchanger, and a temperature control device for controlling the temperature of the outdoor heat exchanger. In an outdoor unit of an air conditioner comprising a temperature detection sensor for detecting and an outdoor blower for air cooling the outdoor heat exchanger, etc., the temperature of the outdoor heat exchanger is detected by the temperature detection sensor, and the temperature of the outdoor heat exchanger is detected. When the result exceeds a reference value preset in the microcomputer, the operation of the compressor is stopped.

[Effect]

With the above configuration, when the outdoor fan stops during cooling operation, the temperature of the outdoor heat exchanger will rise rapidly, but this sudden temperature increase will be detected by the temperature detection sensor and compared with a preset reference value. This makes it possible to determine whether to stop the outdoor blower, and if the determination result exceeds the reference value, the control signal sent from the microcomputer to the inverter device can be stopped, and the operation of the compressor can be stopped.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 3.

Figure 1 shows the refrigerant circuit of an air conditioner, where 1 is the compression number 2 is a four-way valve that switches the refrigerant flow depending on whether it is in cooling or heating mode, 3 is the outdoor heat exchanger, 4 is the capillary tube, and 5 is the refrigerant circuit.
indicates an indoor heat exchanger, these are connected with pipes in a ring shape, a temperature detection sensor 6 and an outdoor blower 7 are on the outdoor heat exchanger 3 side, and a number on the indoor heat exchanger 5 side is an indoor blower. 8
and a microcomputer (not shown) are respectively provided.

FIG. 2 is a perspective view of the outdoor unit, in which the compressor 1, four-way valve 2 (not shown), etc. are installed near one example of the base 9.
On the other side partitioned by the partition plate 10, there is an outdoor heat exchanger 3,
A temperature detection sensor 6 and an outdoor blower 7 are provided, and an inverter device 11 for controlling the compressor 1 is attached to the partition plate IO.

Although not shown, the partition plate 10 to which the inverter device 11 is attached has a shape that allows ventilation, and while the outdoor blower 7 is in operation, the inverter device 11 is air-cooled together with the outdoor heat exchanger 3.

The main body of the inverter device 11 is composed of a plurality of electrical components, and the outside thereof is shielded by a metal case so as not to be affected by external noise.

This inverter device 11 operates based on a control signal transmitted from a microcomputer (not shown) provided on the indoor unit side, and controls the rotation speed of the compressor 1.

The temperature detection sensor 6 is originally provided to detect frost formation that occurs during heating operation, but in the present invention, this temperature detection sensor 6 is also used during cooling operation to detect frost formation on the outdoor heat exchanger 3. The system is designed to detect abnormal temperatures.

By the way, in cooling operation, when the rotation speed of the compressor 1 increases, the temperature of the outdoor heat exchanger 3 detected by the temperature detection sensor 6 increases.
The temperature also increases as shown in FIG.

If the operation of the outdoor fan 7 is stopped due to a failure of the microcomputer or the like during this cooling operation, the outdoor heat exchanger 3 will no longer be air cooled, and sufficient heat exchange will not be possible, so that the temperature of the outdoor heat exchanger 3 exceeds the characteristic value shown in FIG.

The temperature characteristics of the outdoor heat exchanger 3 are stored in advance in the microcomputer in comparison with the operating frequency of the compressor as shown in FIG. The temperature is repeatedly compared and determined at predetermined time intervals, and when the temperature of the outdoor heat exchanger 3 is in the stop region shown in FIG. 3, it is determined that the outdoor blower 7 is stopped,
The output of the control signal to the inverter device is cut off, and the operation of the compressor 1 is controlled to be stopped.

In this way, by detecting the temperature of the outdoor heat exchanger and comparing it with a reference value preset in the microcomputer, it is possible to determine that the operation of the outdoor fan has stopped.
Based on the determination result, the control signal to the inverter device can be cut off, and the operation of the compressor can be stopped.

〔Effect of the invention〕

If the air conditioner is controlled as explained above, it can be easily determined that the outdoor fan has stopped operating from the temperature of the outdoor heat exchanger, and based on the determination result, the inverter device can be Since the control signal can be cut off and the operation of the compressor can be stopped, the electrical components of the inverter device are not adversely affected by self-heating or an increase in ambient temperature, and safety is also improved.

[Brief explanation of the drawing]

FIG. 1 is a refrigerant circuit diagram of an air conditioner showing one embodiment of the present invention, FIG. 2 is a perspective view of the main parts inside the outdoor unit of the same embodiment, and FIG.
The figure is a characteristic diagram showing the relationship between compressor operating frequency and outdoor heat exchanger temperature in the same example. In the figure, 1-...Compressor, 2-Four-way valve, 3-Outdoor heat exchanger, 4-Capillary tube, 5-Indoor heat exchanger, 6-Temperature detection sensor, 7-Outdoor ventilation edge 8--Indoor blower, 9--Base, 10-Oshikiri board, 11
...Inverter device.

Claims (1)

[Claims] A compressor, an inverter device that controls the rotation speed of the compressor, an outdoor heat exchanger, a temperature detection sensor that detects the temperature of the outdoor heat exchanger, and air cooling of the outdoor heat exchanger, etc. In an outdoor unit of an air conditioner equipped with an outdoor blower, etc., the temperature of the outdoor heat exchanger is detected by the temperature detection sensor, and when the detection result exceeds a reference value preset in the microcomputer, the compression An air conditioner characterized in that the operation of the machine is stopped.