JPS6011048A - Air-conditioner - Google Patents

Abstract

PURPOSE:To contrive the torque increase as well as the input current reduction of a compressor motor upon overload of room heating and permit the always stabilized operation of the compressor by a method wherein an operation capacitor for an outdoor fan motor is conncted in parallel to the operation capacitor for the compressor motor when the operation of the outdoor fan is stopped upon the overload of room heating. CONSTITUTION:The temperature of an indoor heat exchanger 5 is being detected by an indoor heat exchanger temperature sensor 15 upon room heating operation and when the detected temperature has become higher than a predetermined value, a main control unit 12 dicides that the operation is brought into an overload condition and puts off a relay contact 12c. When the relay contact 12c is put OFF, the operation of the outdoor fan motor 6m is stopped. According to this method, the reduction of load may be contrived. The operation of relay 17 is also stopped simultaneously with the OFF of the relay contact 12c and the always closed side of the contact 17a is closed to connect the operation capacitor 18 in parallel to the operation capacitor 19. As a result, the operation capacitors 18, 19 are thrown into the compressor motor 1m.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an air conditioner that uses single-phase induction motors as power sources for a compressor and a fan motor, respectively.

[Technical background of the invention]

2. Description of the Related Art Conventionally, some home heat pump air conditioners using a commercial AC power source use single-phase induction motors as power sources for a compressor and a fan motor, respectively.

In this case, each motor is connected to an operating capacitor that also serves as a starting capacitor.

By the way, in such air conditioners, during heating operation, the load condition is monitored by detecting the high pressure side pressure or the indoor heat exchanger temperature, and when an overload condition occurs, the operation of the outdoor fan is stopped and the load is We are trying to reduce this. In other words, this is because when an overload condition occurs, the compressor motor (hereinafter referred to as the compressor motor) will break down due to insufficient torque, and the input current of the compressor motor will become too high. .

However, when the wind is strong, even if the operation of the outdoor fan is stopped, the amount of heat exchanged by the indoor heat exchanger cannot be reduced, and the load cannot be reduced. As a result, problems such as those described above often occur, making stable operation of the compressor difficult.

[Purpose of the invention]

This invention was made in view of the above circumstances,
The purpose is to provide an air conditioner that can increase the torque of the compressor motor and reduce the input current during heating overload, and that enables stable operation of the compressor at all times.

[Summary of the invention]

This invention focuses on the characteristic that the larger the capacity of the operating capacitor, the larger the torque of the single-phase induction motor, and the smaller the input current. The operating capacitor for the motor is connected in parallel to the operating capacitor for the sardine machine motor.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

First, the rotation speed-torque characteristic and load-input terminal characteristic of a single-phase induction motor are shown in FIGS. 1 and 2, respectively, using the capacity of the operating capacitor as a parameter. That is, the larger the capacity of the operating capacitor, the larger the torque. Further, when the load is small, the smaller the capacity of the operating capacitor, the smaller the input current, but when the load is larger, the larger the capacity of the operating capacitor, the smaller the input current can be.

As shown in FIG. 3, the compressor 1° four-way valve 2.
Outdoor heat exchanger 3. Pressure reducing device (Example: expansion valve) 4. The indoor heat exchanger 5 and the like are successively connected to form a heat pump type refrigeration cycle.

In this case, during the cooling operation, the refrigerant flows in the direction of the solid arrow shown in the figure, and during the heating operation, the refrigerant flows in the direction of the broken line arrow as shown by the switching operation of the four-way -7P2. An outdoor fan 6 is arranged near the outdoor heat exchanger 3, and an indoor fan 7 is arranged near the indoor heat exchanger 5.

FIG. 4 shows the control circuit. 10 is a commercial AC power source, and a main control section 12 is connected to this power source 10 via a transformer ll'ff. The main control section 12 is composed of a microcomputer, various relays, etc., and operates the relay contacts 12a according to commands from the operation section 13, the output of the indoor temperature sensor 14, the output of the indoor heat exchanger temperature sensor 15, etc.

12b, 12c, and 12d. 〇The power source 10 is connected to an indoor fan motor (single-phase current motor) via a relay contact 12a.

A 7 m long main winding M is connected to the main winding M, and an auxiliary winding A is connected in parallel to the main winding M via a 16'ft running capacitor which also serves as a start-up. Furthermore, the power supply 10 has a relay contact 12bf.
: The four-way valve 2 is connected through. Further, the main winding M of the outdoor fan motor 6m and the excitation coil 17t of the relay 17 are connected to the power supply 10 via the relay contact 12c, and the main winding M is used for both the normally open side and the starting side of the relay contact 77a. The auxiliary winding A is connected in series with the operating capacitor 18 . Furthermore, the main winding M of the compressor motor 1m is connected to the power supply 10 via a relay contact 12d, and the main winding MK is connected to an auxiliary winding A via an operation capacitor J9 which also serves as a start-up. The operating capacitor 18 is connected in parallel to the operating capacitor 19 via the normally closed side of the relay contact 17a.

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

Now, when the heating operation is started using the operation unit 13, the relay contacts 12a+12b*12cr12d are turned on, the four-way valve 2 is switched, and the indoor fan motor 7m, outdoor fan motor 6m, and compressor motor 1m are switched on. Start each 〇 In this way, heating operation starts. In this case, the operation capacitor 18 is connected to the outdoor fan motor 6m by activating the relay 17 by turning on the relay contact 12c. Note that, due to the operation of the relay 17, the operating capacitor 18 is disconnected from the compressor motor 1m.

By the way, during this heating operation, the temperature of the indoor heat exchanger 5 is detected by the indoor heat exchanger temperature sensor 15, and when the detected temperature exceeds a certain value, the main control unit 12 becomes overloaded. It is determined that the relay contact 12c is turned off. When the relay contact 12c is turned off, the operation of the outdoor fan motor 6m is stopped, and the operation of the outdoor fan 6 is stopped. For this,
The load is reduced. At the same time, the operation of the relay 17 is also stopped by turning off the relay contact 12c, the normally closed side of the contact 17a is closed, and the operating capacitor 18 is connected to the operating capacitor 1.
9 is connected in parallel. The operating capacitors 18 and 19 are connected to the compressor motor 1m.

In this way, by increasing the capacity of the operating capacitor for 1 m of compressor motor during heating overload, the torque of 1 m of compressor motor 1 m can be increased and the input current can be reduced as explained in Figs. 1 and 2. can be measured. Therefore, even though the outdoor fan 6 has stopped operating, the amount of heat exchanged by the outdoor heat exchanger 3 does not decrease due to strong wind, for example.
Even if the load cannot be reduced, the compressor 1 can be operated stably without causing a brake down. In particular, if you are trying to increase the capacity of the operating capacitor for 1 m of compressor motor, it may be possible to increase the capacity of the operating capacitor 19 from the beginning, but this poses the problem of increasing costs. Taking this into consideration, it is extremely effective in practice to use the operation capacitor 18 for the outdoor fan motor.

On the other hand, the relay contact 12b is turned off and the four-way valve 2 is restored.
In addition, when the relay contact 12Q is turned off and the operation of the indoor fan 6 is stopped, the indoor heat exchanger 5 is operated to remove the side. As in the case of an overload, both operating capacitors 18 and 19 are connected to the compressor motor 1m. During this unregistered operation, the load is reduced and
If the capacity of the operating capacitor increases in this state, the input current to the compressor motor 1m increases, as is clear from FIG. As the input current increases, the rotation speed of the compressor motor 1m increases, and an increase in torque can be measured. If the torque increases, the capacity of the compressor 1 increases, the defrosting capacity increases, and the defrosting time can be significantly shortened.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without changing the gist.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to increase the torque of the compressor motor and reduce the input current during heating overload, thereby providing an air conditioner that enables stable operation of the compressor at all times. .

[Brief explanation of the drawing]

Fig. 1 is a rotation speed-torque characteristic diagram of a single-phase induction motor according to the present invention, Fig. 2 is a precious load-input terminal characteristic diagram of a single-phase induction motor according to the present invention, and Fig. 3 is an embodiment of the present invention. FIG. 4 is a block diagram of the heat & pump type refrigeration cycle in the example, and FIG. 4 is a block diagram of the control circuit in the same embodiment. 1... Pressure m machine, 1m... Compressor motor (single phase induction motor), 6... Outdoor fan, 6m... Outdoor fan motor (single phase induction motor), 12... Main control unit , 17・
... Relay, 18... Operating capacitor for outdoor fan motor, 19... Operating capacitor for compressor motor. Applicant Patent Attorney Takehiko Suzue Figure 1 @ Figure 2 Figure 3 - Figure 4 Figure 0

Claims (1)

[Claims] A heat pump refrigeration cycle consisting of a compressor powered by a single-phase induction motor, a four-way valve, an outdoor heat exchanger, a pressure reducing device, an indoor heat exchanger, etc. connected in sequence, and an operating capacitor for the compressor motor; An outdoor fan powered by a single-phase mower motor, an operating capacitor for the outdoor fan motor, a control means for stopping the outdoor fan when an overload condition occurs during heating operation, and stopping the operation of the outdoor fan. and control means for connecting an operating capacitor for the outdoor fan motor in parallel to the operating capacitor for the compressor motor.