JPH0544666Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) This invention relates to a split-type air conditioner consisting of an indoor unit and an outdoor unit.

(Prior art) A split type air conditioner connects the indoor unit and outdoor unit with connectors and crossover wires (electric wires).
The electrical connection is made through a screwless connector, and many screwless connectors are used because of their ease of operation. An example of this screwless connector is shown in FIGS. 3 and 4.

Reference numeral 1 denotes a main body of a screwless connector, which has a wire insertion port 2, a release button 3, a leaf spring 4, a terminal plate 5, and the like. That is, the release button 3 is pressed against the biasing force of the leaf spring 4, and the wire 6 is inserted into the wire insertion opening 2. Then, the core wire 6a of the electric wire 6 passes through the hole of the release button 3, enters the main body 1, and comes into electrical contact with the terminal plate 5. In this state, release button 3
When the pressure is released, the release button 3 is pushed up by the biasing force of the leaf spring 4, and the release button 3 is pushed up.
The core wire 6a is sandwiched between the step between the hole and the wire insertion port 2. In other words, electrical and mechanical connections can be easily made by simply inserting the electric wires 6.

However, when actually connecting the crossover wires during on-site installation, there are cases where the crossover wires are not inserted into the connectors enough, or wires other than those specified are used as the crossover wires. The disadvantage is that mistakes are likely to occur.
If the air conditioner continues to operate due to construction errors, the terminals inside the connector may overheat abnormally, which in the worst case may lead to a fire.

(Problem that the invention aims to solve) This invention was made in view of the above circumstances, and its purpose is to prevent abnormal overheating of the connector and the occurrence of fire due to construction errors during installation. Our objective is to provide an air conditioner that can prevent this.

[Structure of the invention] (Means for solving the problem) This invention is an air conditioner that connects an indoor unit and an outdoor unit with a power line and is equipped with a connector for connecting the power line. or a thermally responsive switch that is attached to a power line and connected to a control line and operates when the sensed temperature exceeds a predetermined value; means for detecting the operation of the thermally responsive switch through the control line; and a means for detecting the operation of the thermally responsive switch through the control line; means for zeroing the current flowing through the line.

(Function) When the temperature of the connector or power line exceeds a predetermined value, the thermal response switch is activated. This activation is detected via the control line, and upon detection the current flowing through the power line is reduced to zero.

(Example) An example of this invention will be described below with reference to the drawings.

First, the control circuit is shown in FIG.

That is, A is an indoor unit and B is an outdoor unit. In the indoor unit A, 10 is an indoor control section consisting of a microcomputer and its peripheral circuits, and is connected to a commercial AC power source 11. The indoor control unit 10 is connected to a remote control operation unit 12, an indoor temperature sensor 13, a display unit 14, and a fan motor drive circuit 15. This fan motor drive circuit 15 drives an indoor fan motor 16.

On the other hand, in the outdoor unit B, 20 is an outdoor control section consisting of a microcomputer and its peripheral circuits. , four-way valve 25
is connected. The inverter circuit 23 once rectifies the AC power supply voltage, converts it into AC power of a predetermined frequency and voltage by switching, and supplies the AC power to the compressor motor 26. four-way valve 25,
The refrigerant flow direction in the refrigeration cycle is switched between cooling and heating.

Also, connect the screwless connector 3 to indoor unit A.
0. The outdoor unit B is provided with a screwless connector 40. The screwless connector 30 includes three screwless connectors 31, 32, and 33, each having the same structure as shown in FIGS. 3 and 4. Similarly, the screwless connector 40 has three screwless connectors 41, 4.
It has 2,43.

Therefore, from the indoor control unit 10 to the connector 31,
32 are connected to power supply lines 51 and 52, respectively, and a control signal line 53 is connected from the indoor control unit 10 to the connector 33 as a control line. A thermally responsive switch, such as a temperature fuse 80, is connected to this control signal line 53. The temperature fuse 80 is activated, ie, blown, when the sensed temperature exceeds a predetermined value, and functions to cut off the control signal line 53. Power lines 61 and 62 are connected to the outdoor control unit 20 from the connectors 41 and 42, respectively, and the power lines 61 and 62 are connected to the outdoor control unit 2 from the connector 43.
A control signal line 63 is connected to 0.

The connectors 31 and 41 are connected by the crossover wire 71, and the connectors 32 and 42 are connected by the crossover wire 72, thereby forming a commercial AC power line from the indoor control section 10 to the outdoor control section 20. In addition, the connectors 33 and 43 are connected by a crossover wire 73 to form a control signal line (serial signal line).

Here, the configuration of the peripheral portion of the connector 30 is shown in FIG.

The power wires 51, 52 and the control signal wire 53 are bundled together, and the temperature fuse 80 inserted into the control signal wire 53 is connected to the power wires 51, 52 near the connector 30 with an insulating tape 90. It is attached and held in close contact with the Note that the illustrated broken line indicates a soldered connection between the control signal line 53 and the temperature fuse 80.

The outdoor control unit 20 includes a functional means for detecting the melting of the temperature fuse 80 through the control signal line 53 (and crossover wire 73), and a function means that stops all operations and zeros the current flowing through the power supply lines 51 and 52 when this melting is detected. It has functional means to

Next, the operation in the above configuration will be explained.

Desired operating conditions are set using the operating unit 12, and a driving start operation is performed. Then, indoor control unit 1
0 through the control signal line, control commands such as operation ON command and operation frequency setting command are converted into serial signals synchronized with the power supply frequency and sent to the outdoor control unit 2.
Transferred to 0. Then, the outdoor control unit 20 switches and drives the inverter circuit 23, supplies driving power to the compressor motor 26, and turns on the compressor. In other words, the operation begins.

By the way, during this operation, the power line has 15~
A large current of about 20A flows. Therefore, if the connection between the crossover wire 71 or 72 and the connector is not made securely during installation (poor contact), the contact resistance at the connection will increase, causing the connector to overheat and become dangerous. Become.

Thus, for example, when the temperature of the connector 30 increases, this is transmitted to the temperature fuse 80, and the temperature sensed by the temperature fuse 80 increases. Then, when the sensed temperature exceeds a predetermined value, for example 80℃ or higher,
The temperature fuse 80 blows and the control signal line is cut off. In other words, transfer of control commands from the indoor control section 10 to the outdoor control section 20 is prohibited. Then, the outdoor control unit 20 stops all operations.
In this way, by stopping the operation of the outdoor unit B, the current flowing through the power supply line becomes zero, and abnormal overheating can be avoided. Therefore, the occurrence of fire can be prevented.

Furthermore, since the temperature fuse 80 is inserted into the control signal line with a small current, a temperature fuse with a small rated current can be used, making it compact and inexpensive.

In the above embodiment, the temperature fuse 80 is attached to the power supply wires 51 and 52, but the connector 3
It may be attached to the front or back side of 0. Further, although the temperature fuse 80 is provided only on the indoor unit A side, it may also be provided on the indoor unit B side, thereby further improving safety.

Further, the thermally responsive switch is not limited to a temperature fuse, but a bimetallic thermostat, a positive temperature coefficient thermistor, or the like may be used. In particular, positive temperature coefficient thermistors have the advantage of being inexpensive and highly reliable.
However, unlike a temperature fuse, a positive temperature coefficient thermistor is a self-resetting type, so measures must be taken to control the set temperature and when the fuse is restored, such as not turning it on for a predetermined period of time after restoration.

Furthermore, although the application to an air conditioner has been described, the present invention can be similarly applied to other devices as long as electrical connections are made using connectors.

[Effects of the invention] As described above, according to this invention, a thermally responsive switch that operates when the temperature of the connector or power line exceeds a predetermined value is provided, and the operation of the thermally responsive switch is detected via the control line. When detecting this, the current flowing through the power line is reduced to zero, so
It is possible to provide an air conditioner that can prevent abnormal overheating of connectors and fire occurrence due to construction errors during installation.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the configuration of the main parts of an embodiment of this invention, Figure 2 is a diagram showing the configuration of the control circuit of the same embodiment, and Figures 3 and 4 are respectively typical screwless connectors. FIG. A...Indoor unit, B...Outdoor unit, 3
1, 32, 33, 41, 42, 43... Screwless connector, 53, 63... Control signal line, 71, 7
2, 73...Covering wire, 80...Temperature fuse (thermal response switch).

Claims (1)

[Scope of utility model registration request] In an air conditioner that connects an indoor unit and an outdoor unit with a power line and is equipped with a connector for connecting the power line, when the unit is attached to the connector or the power line and is connected to the control line, the sensed temperature exceeds a predetermined value. A thermally responsive switch that operates when
An air conditioner comprising: means for detecting the operation of the thermally responsive switch through the control line; and means for reducing the current flowing through the power supply line to zero when the operation is detected.