JPS6038106Y2 - Air conditioner control circuit - Google Patents

Description

[Detailed description of the invention] The present invention relates to a control circuit for an air conditioner for variable control of power saving in multiple stages, in which a part of the discharge amount of the compressor can be returned to the suction side. .

Conventionally, the control circuits for saving the cooling capacity of air conditioners include two methods: ■ Switching the cooling capacity to full power or power saving depending on the indoor temperature, and ■ Switching the cooling capacity to full power depending on the outdoor temperature. There was a method to switch between power saving and power saving.

However, both methods ■ and ■ can only save one level, and in method ■, when the outside temperature is low, even if the indoor cooling load is large, the power is saved and the cooling capacity is insufficient. There was a drawback.

Furthermore, when attempting to perform two-stage saving using method (2), the control method becomes complicated, and the number of connection lines for connecting the indoor and outdoor units increases.

This invention was made to improve the above-mentioned drawbacks.
The indoor unit on the power supply side and the outdoor unit on the compressor side are connected by three connecting wires, and a switch is provided on the indoor unit side for switching whether or not to save the cooling capacity depending on the indoor temperature, and the above-mentioned A save switch is provided on the outdoor unit side to switch between first-stage save and second-stage save depending on the outside temperature.

With such a simple configuration, the saving of cooling capacity can be varied in multiple stages.

Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a refrigerant circuit of an air conditioner controlled by a control circuit according to the present invention.

In this figure, 1 is a rotary compressor, and a discharge pipe 2 of this compressor 1 includes a condenser 3, first and second pressure reducers 4, 5.
and an evaporator 6 are successively connected, and the output side of the evaporator 6 is connected to the suction pipe 7 of the compressor 1 to constitute a refrigeration cycle.

A conduit in which a first electromagnetic valve A and a check valve 8 are inserted in series is connected to the first pressure reducer 4 in parallel.

This check valve 8 is connected from the low pressure side of the first pressure reducer 4 to the first
It is inserted in the direction of blocking the flow to the low pressure side of the solenoid valve A.

The compressor 1 is specifically constructed as shown in FIGS. 3 and 4.

In FIG. 3, reference numeral 1 denotes a compressor, and the compressor 1 is configured such that a rotating shaft 9 of a motor is directly connected to an eccentric position of a rotor 12 in an inner chamber 11 of a cylinder 10 and rotates.

The left and right end surfaces of the cylinder 10 are closed by a main frame and a subframe.

The cylinder 10 is formed with a suction hole 13 and a discharge hole 14 communicating with the inner chamber 11, and one ends of the suction pipe 7 and the discharge pipe 2 are press-fitted into the suction hole 13 and the discharge hole 14. , the other ends of each are connected to an evaporator 6 and a condenser 3, as shown in FIG.

In the cylinder 10, a first bypass hole 15 is provided in the inner chamber 11.
A first valve seat 16, a disc-shaped valve body 17, a valve seat support spring 18, and a second valve seat 19 are formed in this first bypass hole 15 in order from the inner chamber 11 side. When inserted, an on-off valve 20 is constructed, and the valve body 17 is arranged so as to be freely movable in a space formed between the first valve seat 16 and the second valve seat 19.

As shown in FIG. 4, the second valve seat 19 is made of a ring body with an uneven peripheral surface on the inside and a gap 21 formed in one part, and has an annular groove bored in the first bypass hole 15. It is fitted and fixed.

One end of a first bypass pipe 22 as a first return path is press-fitted into the first bypass hole 15.
A second solenoid valve B is inserted in the middle of the second solenoid valve B, and the other end is the first solenoid valve B.
As shown in the figure, it is connected to the suction pipe 7 of the compressor 1.

In this way, the on-off valve 20 is operated by the valve body 1 due to the pressure difference between the inner chamber 11 of the cylinder 10 and the first bypass pipe 22.
7 is in close contact with the first valve seat 16, the first bypass hole 15
is closed, and when the valve body 17 is brought into close contact with the second valve seat 19,
High pressure gas flows into the inner chamber 11 of the cylinder 10 through the space 23 created between the outer circumferential edge of the valve body 17 and the inner circumferential edge of the second valve seat 19.
The first bypass pipe 22 is configured to flow from the first bypass pipe 22.

A second bypass pipe 24 communicating with the inner chamber 11 is provided on the main frame that closes the right end surface of the cylinder 10,
One end of a second bypass pipe 25 serving as a second return path is press-fitted into the second bypass hole 24 .

As shown in FIG. 1, this second bypass pipe 25 has a third solenoid valve C inserted in its middle, and the other end is connected to the suction pipe 7 of the compressor 1.

Reference numeral 26 denotes a gate valve that divides the inner chamber 11 of the cylinder 10 into a high pressure chamber and a low pressure chamber, and is configured to abut against the rotor 12 by a spring 27.

FIG. 5 shows a control circuit according to the present invention, which controls the refrigerant circuit constructed as described above.

The same parts as in FIG. 1 are given the same reference numerals.

In this figure, 28 is an indoor unit, 29 is an outdoor unit, and these units 28, 29 have three corresponding connection terminals 30, 31, 32, 33, 34, and 35 connected to one power supply line 37, which will be described later. The power supply connection line A is connected to the power supply connection line A branch connection line from this power supply line 37 to the power supply connection line connected to the other power supply line 38 .

The indoor unit 28 is constructed as follows.

Power line 3 connected to plug 36 for AC power supply
A 3-minute timer 39 that outputs an output signal after 3 minutes has passed after inputting the signal, and a remote control unit 40 are connected to 7° 38, and one power supply line 37 is connected to the connection terminal 30 via a main relay switch 41, The power supply line 38 of is connected to the direct connection terminal 34.

The remote control unit 40 includes a timer 42 for setting the operating time, a first operation switch 43, a second operation switch 45 for changing the speed of the fan motor 44 on the indoor side, and a power save switch (hereinafter referred to as (simply called a circle switch) 46, and a common contact 47 depending on the temperature of the room temperature.
It consists of an indoor thermoswitch 49 that automatically switches the side movable piece 48 between H contact H and L contact.

The switch 46 is connected to the connection terminal 32 via a first relay switch 50, and the indoor thermo switch 49
The H contact H is connected to the input side of the 3-minute timer 39 via a second relay switch 51, and the L contact is connected to the power supply line 38 via a high resistance 52.

The three-minute timer 39 is configured to turn on the main relay switch 41 in response to a signal appearing on its output side.

The common contact 47 of the indoor thermo switch 49 is connected to a common contact 55 on the side of the movable piece 54 of the switch 53 for switching between cooling and heating.

The thermo side contact 56 of the changeover switch 53 is connected to the resistor 5.
7 and the power line 38 via the pilot lamp 58
The cooling side contact 59 is connected to the power line 38 via a resistor 60 and a pilot lamp 61, and is also connected to the power line 38 via an excitation coil 62 that drives the eleventh second relay switch 50.51. It is connected.

A resistor 63 and a PS pilot lamp 64 are connected in series between the connection terminals 32 and 34.

The outdoor unit 29 is constructed as follows.

The compressor 1 and an outdoor fan motor 65 are connected between the connection terminals 31 and 35, and a common contact 68 on the movable piece 67 side of the electromagnetic changeover switch 66 is connected to one of the connection terminals 31.

The on-side contact 69 of this electromagnetic changeover switch 66 is connected to the second excitation coil b for driving the second solenoid valve B, and the off-side contact 70 is connected to the first excitation coil a for driving the first solenoid valve A. Each of the two terminals is connected to the other connecting terminal 35 via the connecting terminal 35 of the other terminal.

71 is a movable piece 73 on the common contact 72 side depending on the outdoor temperature.
is an outdoor thermoswitch that switches between H contact H on the high temperature side and L contact on the low temperature side.The common contact 72 of this thermoswitch 71 is connected to the connection terminal 33, and the L contact is connected to the electromagnetic changeover switch 66. It is connected to the connection terminal 35 via an excitation coil 74 for driving the movable piece 67 toward the on-contact 69 side, and the H contact H is open.

A third excitation coil C for driving a third electromagnetic valve C is connected between the connection terminals 35 and 35.

Next, the operation of the present invention will be explained.

First, the operation of the compressor 1 will be explained.

When power is supplied to the motor and the rotating shaft 9 rotates, the eccentric rotor 12 within the cylinder 10 rotates.

Now, when this rotor 12 starts rotating in the direction of the arrow from the position shown in FIG.
0 is discharged to the condenser 3 side outside the 0.

At the same time, the cylinder 10 is
A new refrigerant is sucked into the inner chamber 11 of the refrigerant.

This newly sucked refrigerant is then discharged to the outside of the cylinder 10 via the discharge pipe 2 by the next rotation of the rotor 12 .

In this way, two revolutions of the rotor 12 result in one suction, one compression, and one discharge.
A cycle process takes place.

Next, power is supplied from the plug 36 of the control circuit shown in FIG. Set it to the cooling side.

Further, assuming that the movable piece 48 of the indoor thermo switch 49 is on the H contact H side, the pilot lamp 61 for cooling lights up to indicate that the air conditioner is in the cooling mode, and the relay coil 62 is energized and the first, Second relay switch 50.
51 is turned on, and the timer 39 is activated for three minutes.

After three minutes have elapsed, the main relay switch 41 is actuated by the output of the three-minute timer 39, and power supply voltage is supplied between the connection terminals 30 and 34.

This power supply voltage is supplied to the compressor 1 and fan motor 65 on the outdoor unit 29 side via the connection terminals 31 and 35, and also excites the first excitation coil a to open the first solenoid valve A.

At this time, the other second and third excitation coils b and c are not excited.

Therefore, in the refrigerant circuit shown in Fig. 1, the first solenoid valve A is open and the second solenoid valve
Solenoid valve B is closed and third solenoid valve C is closed.

Therefore, the high-pressure refrigerant gas discharged from the compressor 1 is sent to the condenser 3 via the discharge pipe 2, where it is condensed and liquefied, and passes through the first electromagnetic valve A1 check valve 8 and the second pressure reducer 5. The pressure is reduced in the evaporator 6, and the air is evaporated in the evaporator 6, and then returns to the compressor 1 via the suction pipe 7.

At this time, the first bypass pipe 2 is inserted into the first bypass hole 15.
High pressure refrigerant liquid is introduced via 2.

Since the pressure inside this first bypass hole 15 is higher than that in the inner chamber 11 of the cylinder 10, the valve body 17 of the on-off valve 20 is
It is pressed against the valve seat 16 to close the first bypass hole 15.

As described above, when the second and third solenoid valves B and C are closed and the first solenoid valve A is open, the maximum amount of refrigerant passes through the evaporator 6, so the maximum capacity (that is, the save rate, 0) is reached. It will be in a cooling state.

Next, the indoor cooling load decreases, and the indoor unit 2
When the circle switch 46 of No. 8 is turned on automatically or manually, the first relay switch 50 is already closed.
Power supply voltage is also supplied between the connection terminals 33 and 35 of the outdoor unit 29.

Therefore, the third excitation coil C is excited and the third electromagnetic valve C is opened to enter a cooling capacity saving state.

Here, if the outdoor temperature is higher than the predetermined temperature, the movable piece 73 of the outdoor thermoswitch 71 becomes the H contact H side, the excitation coil 74 is demagnetized, the electromagnetic changeover switch 66 is not operated, and the first electromagnetic valve A is During this period, the second solenoid valve B is in a closed state.

Therefore, a part of the refrigerant in the inner chamber 11 of the cylinder 10 returns to the suction pipe 7 of the compressor 1 through the second bypass hole 24 and the second bypass pipe 25, and part of the refrigerant discharged from the discharge pipe 2 of the compressor 1 is The amount decreases slightly, and the cooling capacity of the device decreases by approximately 10%.
% decrease (save rate 10%).

On the other hand, when the outdoor temperature is lower than a predetermined temperature, the movable piece 73 of the thermoswitch 71 becomes the L contact side, which excites the excitation coil 74 and switches the movable piece 67 of the electromagnetic changeover switch 66 to the on contact 69 side. The first solenoid valve A is closed, and the second solenoid valve B is opened.

In this state, the high pressure applied to the on-off valve 20 from the condenser 3 side is released, and the valve body 17 is moved to the second valve seat 1.
Close it to the 9 side and open it.

Therefore, part of the refrigerant in the inner chamber 11 of the cylinder 10 is transferred to the first bypass hole 15, the on-off valve 20 and the first bypass pipe 2.
2, the refrigerant returns to the suction pipe 7 of the compressor 1, and the amount of refrigerant discharged from the discharge pipe 2 of the compressor 1 is reduced by about 30% due to the first bypass pipe 22 alone.

At this time, since the third electromagnetic valve C is also open (save rate 10%), the overall cooling capacity save rate is approximately 40%.

As mentioned above, the first, second,
By controlling the third solenoid valves A, B, and C and the on-off valve 20, the cooling capacity can be set not only at maximum but also at a save rate of 10.
It can be varied in three stages: % and 40%.

In the embodiment described above, the control section for controlling the opening and closing of the on-off valve 20 of the refrigerant circuit was composed of the second electromagnetic valve B and the check valve 8, but the present invention is not limited to this, and the first Any device that controls the opening and closing of the on-off valve 20 by controlling the pressure applied to the high-pressure side of the bypass hole 15 may be used.

For example, as shown in FIG.
A second solenoid valve B is connected to the bypass pipe 22, and a second solenoid valve B is connected to this connection part.
By inserting a three-way valve a instead of the three-way valve a and controlling the three-way valve a in the same manner as the second electromagnetic valve B according to the magnitude of the cooling load, the cooling capacity can be saved.

That is, when the PS switch 46 is off, the three-way valve a is not energized, and the three-way valve B1 is in the state shown by the solid line in FIG. are doing.

The same applies when the PS switch 46 is turned on and the outdoor thermoswitch 71 is on the H contact H side.

When the PS switch 46 is turned on and the outdoor thermoswitch 71 is on the L contact side, the three-way valve a is energized, rotated 90 degrees as shown by the dotted line in FIG. The bypass pipe 22 communicates with the suction pipe 7 of the compressor 1 .

At this time, the primary side of the three-way valve a may be connected to the output side of the condenser 3, as shown by the dotted line in Figure 2.

In the refrigerant circuit shown in FIG. 2, the three-way valve valve functions as both the solenoid valves A and B in FIG.

That is, when the three-way valve B1 is switched to the position shown by the solid line in FIG. 2, the second on-off valve control path 22a is opened, the second on-off valve 20 is closed, and the first bypass pipe 22 is closed. (corresponds to solenoid valve A open and B closed in Fig. 1), and 3
When the direction valve B1 is rotated 90 degrees and switched to the position shown by the dotted line in Figure 2, the second on-off valve control path 22a is shut off, the high pressure to the second on-off valve 20 is released, and the first bypass pipe 2
2 is in an open state (corresponding to solenoid valve A closed and B opened in FIG. 1).

In the embodiment described above, the first and second pressure reducers 4 and 5 are composed of two pressure reducers, and the connection point thereof is connected to the solenoid valve A for controlling the second on-off valve control path 22a via the check valve 8. The solenoid valve A is connected to the secondary side of the pressure reducer so that the pressure reduction of the pressure reducer can be adjusted, but the present invention is not limited to this.

For example, as shown in FIG. 6, there may be only 1 pressure reducers 4a, and an automatic expansion valve may be used as the pressure reducers 4a.

In this case, the check valve 8 as shown in FIG. 1 is not necessary.

Further, as shown in FIG. 7, even when a three-way valve B□ is used, only one pressure reducer 4a may be used, and an automatic expansion valve may be used as the pressure reducer 4a. The solenoid valve A inserted in parallel to the first pressure reducer 4 as shown in FIG. 2 is not required.

Since the present invention is configured as described above, it has the following effects.

(1) The circuit configuration is simple, and only three connection wires are required to connect indoor and outdoor units.

(2) When the indoor cooling load increases and there is no need to save cooling capacity, the cooling capacity can be maximized (i.e. save rate 0%) by simply turning off the PS switch on the indoor unit side. can.

(3) When the indoor cooling load becomes small and the cooling capacity is to be saved, the outdoor thermoswitch is activated, allowing two levels of saving (for example, 10% save and 40% save) depending on the outdoor temperature.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing an example of a refrigerant circuit of an air conditioner;
Fig. 2 is a circuit diagram showing another example of the refrigerant circuit, Fig. 3 is a sectional view of the cylinder portion of the compressor, Fig. 4 is a front view of the second valve seat in Fig. 3, and Fig. 5 is the present invention. FIGS. 6 and 7 are refrigerant circuit diagrams showing other embodiments of the control circuit for an air conditioner. 1... Compressor, 3... Condenser, 4a.
...Pressure reducer, 4...First pressure reducer, 5...
...Second pressure reducer, 6...Evaporator, 22a.
...Opening/closing valve control path, 22...First return path, 25...Second return path, 28...Indoor unit, 29...・Outdoor unit, 37, 38
...Power line, 41...Main switch, 46...Power save switch, 66
......Electromagnetic changeover switch, 71...Outdoor thermo switch, 74...Exciting coil, A.
...First solenoid valve, B...Second solenoid valve, C
...Third solenoid valve, a...First excitation coil, b...Second excitation coil, C...Third excitation coil, A... ...Power connection wire, port...
...Branch connection line, c...Power connection line.

Claims (1)

[Scope of utility model registration request] A refrigeration cycle is constructed by returning the compressor to the compressor via a condenser, a pressure reducer, and an evaporator, and a part of the discharge amount of the compressor is transferred to a first solenoid valve connected to a second and third solenoid valve, respectively.
1. In a device that controls a refrigerant circuit that returns the refrigerant to the suction side via a second return path, the indoor unit on the power supply side and the outdoor unit on the compressor side are connected to the power line.
The indoor unit has a main switch for supplying power voltage to either one of the two power supply connection lines. The outdoor unit also includes a power save switch for supplying power supply voltage to the branch connection line, and the outdoor unit includes a first solenoid valve that controls discharge from the first return path, and second and third solenoid valves that control discharge from the first return path. It has first, second, and third excitation coils for driving each of the solenoid valves, and includes an electromagnetic changeover switch for switching between the first and second excitation coils and these first and second excitation coils. A series circuit including an excitation coil connected between the two power supply connection lines via the electromagnetic changeover switch and an outdoor thermoswitch that opens and closes depending on the outdoor temperature; and the third excitation coil. A control circuit for an air conditioner, characterized in that the parallel circuit is connected to either the branch connection line or the power supply connection line.