JPS6257898B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air conditioner equipped with a heat pump type refrigeration cycle mainly consisting of a compressor.

Generally, in this type of air conditioner, the indoor unit is equipped with an operation control section having a microcomputer, and the operation of various devices is controlled based on the timer function and temperature control function programmed in the microcomputer. However, there are some systems that perform necessary cooling, heating, and ventilation operations. By the way, in such an air conditioner, during heating operation, it is necessary to defrost the outdoor heat exchanger in the outdoor unit periodically or as needed. A defrost thermoswitch that responds to the temperature of the indoor unit and a defrost timer that sets the defrost time are installed, and the defrost operation is controlled by the operation of the defrost thermoswitch and the defrost timer. This is done independently of the operation control section. That is, this is because the output of the defrosting thermoswitch can only be obtained from the outdoor unit side. However, in this case, even though the operation control section has a timer function, a defrosting timer has to be provided, which is contrary to the always-required simplification of the configuration and cost reduction. .

This invention was made in view of the above circumstances, and its purpose is to eliminate the need for a defrosting timer in the outdoor unit.
This provides a highly practical air conditioner that can simplify the configuration and reduce costs.

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, a heat pump type refrigeration cycle is constructed by sequentially communicating a compressor 1, a four-way switching valve 2, an outdoor heat exchanger 3, a capillary tube 4, and an indoor heat exchanger 5. In this case, during cooling operation, the refrigerant flows in the direction of the solid arrow shown in the drawing, and during heating operation, the four-way switching valve 2 is switched so that the refrigerant flows in the direction of the broken line arrow shown in the drawing. Therefore, the compressor 1, the four-way switching valve 2, the outdoor heat exchanger 3, and the capillary tube 4
The outdoor unit A is constituted by an outdoor blower 6 for circulating outdoor air to the outdoor heat exchanger 3. Further, an indoor unit B is constituted by the indoor heat exchanger 7 and an indoor blower 8 for circulating indoor air to the indoor heat exchanger 7. This indoor unit B is provided with an operation control section (not shown) having a microcomputer programmed with a timer function, a temperature control mechanism, and the like.

FIG. 2 shows the control circuit. Reference numeral 10 denotes an operation control section in indoor unit B. This operation control section 1
0 is a main control section 11 consisting of a microcomputer and its peripheral circuits, an operation unit 12 for giving various operation commands to this main control section 11,
A signal converter 13 that converts the output of a defrosting thermoswitch 30 (described later) into an input signal to the microcomputer of the main controller 11, and a plurality of relays (not shown) in the main controller 11.
A changeover switch (air blower switch) 14, a changeover switch (speed adjustment switch) 1 that responds to each
5. Changeover switch (heating operation setting switch) 1
6. Selector switch (outdoor blower switch) 1
7 and a switch (operation switch) 18. One end of the AC power supply 20 is connected to one end of the blower motor ₇₁ of the indoor blower 7 through the switches 14 and 15 in series, and the other end of the blower motor ₇₁ is connected to the power supply 20. connected to the other end. Further, one end of the four-way switching valve 2 is connected to one end of the power source 20 via the switch 16 and the terminal on the terminal board 21 in series, and the other end of the four-way switching valve 2 is connected via the terminal on the terminal board 21. It is connected to the other end of the power supply 20. In addition, the switch 1 is connected to one end of the power supply 20.
One end of the blower motor ₆₁ of the outdoor blower 6 is connected through the terminals 8, 17 and the terminal board 21 in series, and the other end of the blower motor ₆₁ is connected to the terminal. Furthermore, a terminal plate 2 is provided at the connection point between the switch 18 and the switch 17.
One end of a compressor motor 11 for driving the compressor 1 is connected through the terminal _{at 1} , and the other end of the compressor motor ₁₁ is connected to the terminal. Further, one end of a frosting state detection switch (for example, a defrosting thermoswitch 30) is connected to one end (the above-mentioned terminal) of the power supply 20 through a photocoupler 71 (described later) in the signal converter 13 and a terminal on the terminal board 21 in series. is,
The other end of this defrosting thermoswitch 30 is connected to the above terminal. Defrosting thermo switch 30 above
is provided in the outdoor unit A and responds to the temperature of the outdoor heat exchanger 3.

Here, the operation unit 12 is of a remote control type, for example, and is constructed as shown in FIG. That is, in FIG. 3, the operation surface of the operation unit 12 includes a run/stop switch 41, a timer off switch 42, and a display light emitting diode (hereinafter referred to as
(abbreviated as display LED) 43, 44, sliding timer setting switch 45, sliding operation selection switch 46, sliding air volume adjustment switch 47
A sliding temperature control switch 48 is provided in order from the top to the bottom.

FIG. 4 is a diagram showing the circuit configuration of the operation control section 10. That is, the operating unit 12
A group of operation switches, that is, switches 41, 42, 4
The operation states of 5, 46, 47, and 48 are converted into operation command information by the switch matrix circuit ₁₂₁ , and are input to the input buffer circuit 50 in the main control section 11.
The signal is inputted to a 4-bit one-chip microcomputer (hereinafter abbreviated as microcomputer) 51 via the microcomputer. This microcomputer 51 is programmed with a timer function and a temperature adjustment function in advance. However, the microcomputer 51 has
The timer function and temperature control function are pre-programmed. The microcomputer 51 operates based on the operation command information from the operation unit 12, and the LED driver circuit 52 controls the display LED.
43, 44, and the relay driver circuit 53 operates the switches 14, 15, 1.
Relays 54, 55, 5 corresponding to 6, 17, 18
6, 57, and 58 are selectively operated. Furthermore, the microcomputer 51 is adapted to supply set temperature information in the operation command information from the operation unit 12 to the room temperature detection circuit 59. This room temperature detection circuit 59 is connected to the microcomputer 51
supplies the set temperature information supplied from the output buffer circuit 60 to a digital-to-analog conversion circuit (hereinafter abbreviated as an A-D conversion circuit) 61;
A comparison circuit 63 compares the set temperature signal obtained from this A-D conversion circuit 61 and a room temperature detection signal obtained from a room temperature detector, such as a thermistor 62, and supplies the comparison result information of this comparison circuit 63 to the microcomputer 51. It is. On the other hand, the signal converter 13
When the defrosting thermoswitch 30 is in a closed state, a switching element such as a photocoupler 71
A current flows through the photodiode ₇₁₁ of the photocoupler 71 through the resistor 72, which turns on the phototransistor ₇₁₂ of the photocoupler ₇₁ , and the connection point It is designed so that Furthermore, when the defrosting thermoswitch 30 is in the open state, the signal converting section 13 controls the photocoupler 7.
The first phototransistor ₇₁₂ is turned off, and the connection point X is set to a low potential. Thus, changes in the potential at the connection point X are input to the microcomputer 51 as a defrosting control signal. In addition, the 50/60Hz input of the microcomputer 51 is
This serves as the reference pulse signal for the timer function of the timer, and for example, with a 50Hz input, 1 second is counted with 50 pulses.

Next, the operation in the above configuration will be explained. Now, the indoor blower 7, the four-way switching valve 2, the outdoor blower 6, and the compressor 1 are operated by turning on the switches 14, 16, 17, and 18 under the control of the main control unit 11, thereby performing heating operation. It is assumed that Therefore, when the temperature of the outdoor heat exchanger 3 is, for example, -3° C. or lower and the defrosting thermoswitch 30 is in an open state, that is, when the signal converter 1
When the defrosting control signal from 3 to the microcomputer 51 of the main control unit 11 is at a low potential, this state occurs when the microcomputer 5
When the timer function 1 continues for 50 minutes, the main control unit 11 switches the switches 14, 16,
17 are respectively turned off. In this way, the operations of the indoor blower 7, the four-way switching valve 2, and the outdoor blower 6 are stopped, and the defrosting operation for the outdoor heat exchanger 3 is performed. Afterwards, when the temperature of the outdoor heat exchanger 3 reaches, for example, 5° C. and the defrosting thermoswitch 30 closes, that is, the signal converter 13
When the defrosting control signal to the microcomputer 51 of No. 1 becomes high potential, the main control section 11 controls the switches 14,
16 and 17 are turned on again, and the heating operation is restarted.

Therefore, the timer function of the microcomputer 51 can be used for defrosting operation control, thereby eliminating the need to provide a defrosting timer in the outdoor unit, making it possible to simplify the configuration and reduce costs. Furthermore, when transmitting the output of the defrosting thermoswitch 30 to the operation control section 10, a power line that is common to outdoor unit A and indoor unit B is used. All you need to do is add one crossover wire between the two. In addition, in this case, the output of the defrosting thermoswitch 30 is transmitted to the microcomputer 51 via the signal converter 13, so that the operation control unit 10 is not affected by external noise or the like on the power supply line, and the operation control unit 10 is stable. Operation control is now possible.

Note that this invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the gist of the invention.

As described above, the present invention has the following effects.

Cooling operation/heating operation/
Since all the control circuit switches for defrosting operation are located on the indoor unit side, there is no need to provide control parts in the outdoor unit, making it possible to simplify the configuration and reduce costs.

Since the frost condition detection switch on the outdoor unit is installed between the indoor unit's energized path and the outdoor unit's energized path, the wiring between the indoor and outdoor units is connected to the energized path for the compressor, four-way switching valve, etc. The number of crossover wires between indoor and outdoor units can be kept to a minimum by only increasing the number of wires.

Since the output of the frosting state detection switch passing through the energized path is inputted to the microcomputer via the photocoupler, there is no possibility that the influence of external noise etc. transmitted through the energized path will be transmitted to the microcomputer.

[Brief explanation of the drawing]

The drawings show one embodiment of the invention.
2 is a diagram showing a schematic configuration, FIG. 2 is a diagram showing a configuration of a control circuit, FIG. 3 is a diagram showing a configuration of an operating unit, and FIG. 4 is a diagram showing a circuit configuration of an operation control section. A...Outdoor unit, B...Indoor unit, 1
... Compressor, 2 ... Four-way switching valve, 3 ... Outdoor heat exchanger, 5 ... Indoor heat exchanger, 10 ... Operation control section, 13 ... Signal conversion section, 30 ... Frosting state detection switch (defrost thermo switch).

Claims (1)

[Scope of Claims] 1. An outdoor unit having a compressor, a four-way switching valve, an outdoor heat exchanger, and a pressure reducing device, an indoor unit having an indoor heat exchanger, the compressor, the four-way switching valve, the outdoor heat exchanger, A heat pump type refrigeration cycle in which a pressure reducing device and an indoor heat exchanger are connected in sequence, a current supply path provided from the indoor unit to the outdoor unit to supply electricity to various devices of the outdoor unit, and a power supply path provided in the indoor unit. a switch for opening and closing each of the energizing paths; a means and a timer provided in the indoor unit for controlling cooling operation and heating operation by the switch; and switching between heating operation and defrosting operation by controlling each of the switches. a microcomputer equipped with a means for controlling; a frosting state detection switch provided in the outdoor unit for detecting the frosting state of the outdoor heat exchanger; and a frosting state detection switch provided in the indoor unit and having one end connected to the energizing path of the indoor unit. and a photocoupler whose other end is connected to the energized path of the outdoor unit via the frosting state detection switch, the photocoupler output is input to the microcomputer, and the heating is controlled according to the photocoupler output and the timer means. An air conditioner characterized in that switching between heating operation and defrosting operation is performed by operating means for controlling switching between operation and defrosting operation.