JPS60129547A - Air conditioner - Google Patents

Abstract

PURPOSE:To enlarge the limit of room heating operation and make an electric source throw-in side free by a method wherein the condensing temperature of refrigerant is detected by a sensor to effect peak cut control and prevent the overload operation of the air conditioner. CONSTITUTION:The titled machine is provided with a compressor capacity control circuit 60, controlling the capacity of a compressor 2 baed on the output signal of the condensing temperature sensor 47, detecting the condensing temperature of the refrigerant, so that the capacity of the compressor is reduced in proportion to the rise of the condensing temperature of the refrigerant, and an indoor fan airflow amount control circuit 61, controlling the flow amount of an indoor fan F2 based on the output signal of the condensing temperature sensor 47 so that the flow amount is increased in proportion to the rise of the condensing temperature of the refrigerant. The overload condition upon room heating operation is decided by the condensing temperature of the refrigerant to effect the peak cut operation and prevent the overload operation of the air conditioner while a room heating capacity until the stop of operation of the air conditioner upon the room heating overload operation is controlled stepwisely by two control circuits 60, 61. Thus, the room heating capacity is controlled stepwisely for a period of time until the operation of the air conditioner is stopped, therefore, the limit of operation of the air conditioning machine upon room heating may be enlarged surely.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an air conditioner such as the P1-PO21 type, and particularly to one with an expanded operating limit during heating operation.

(Prior Art) In general, for safety reasons, a so-called peak cut mechanism is well known in heat pump type air conditioners and the like, which stops the operation when an overload condition occurs during heating operation.

As such a peak cut mechanism during heating operation, conventionally, as disclosed in Japanese Patent Publication No. 5'5-2271O, etc., the main current during heating operation of an air conditioner is controlled by a current transformer. A one-transformer system has been proposed which detects this and when the main current rises above a predetermined value, it is considered to be an overload condition and the heating operation is stopped.

However, in the above-mentioned conventional current transformer type 6, the current transformer is expensive, so there is a tendency to increase the cost.

Furthermore, since the air conditioner is operated under one-stage control with only intermittent control depending on the current value of the main current, there is a problem that the operating limit is narrowed.

Moreover, since the main current of the air conditioner is directly detected,
It is necessary to turn on the power from the unit I to which the current transformer is installed among the outdoor unit and the indoor unit of the air conditioner, and there are restrictions on the power-on side.

(Object of the Invention) An object of the present invention is to focus on the fact that the main current of the air conditioner described above is proportional to the condensation temperature of the refrigerant during heating, and to detect the condensation humidity of the refrigerant using an existing sensor. The purpose is to reduce the cost of measures to prevent overload operation of the air conditioner, expand the heating operation limit, and liberalize the power supply side by performing peak cut control.

(Configuration of the Invention) In order to achieve the above object, the configuration of the present invention, as shown in FIG. 1, includes a condensation temperature sensor (47) that detects the condensation temperature of refrigerant during heating in an air conditioner; A compressor cruise ship control circuit (60) that controls the capacity of the compressor 11 (2>) to decrease as the refrigerant condensing temperature rises based on the output signal from the condensing temperature sensor (47); An indoor fan wind ff1lb control circuit (
61).

As a result, the condensation temperature sensor (47) for detecting a temporary overload state during heating can be replaced with a cold air prevention sensor used to prevent cold air from blowing out from the indoor unit during heating operation, and an indoor side during cooling operation. The above two control circuits (60) and (61) can also be used as an antifreeze sensor used to prevent frost formation on the heat exchanger.
Accordingly, the heating capacity is controlled in stages until the air conditioner stops operating during heating overload operation.

(Effects of the Invention) Therefore, according to the present invention, the overload state during heating is determined based on the condensation temperature of the refrigerant, and the condensation temperature sensor that detects the condensation temperature of the refrigerant is replaced by the existing cold air prevention sensor and antifreeze sensor. Furthermore, it is possible to perform peak cut control without requiring a conventional current lance, and it is possible to reduce the cost of measures to prevent overload operation of air conditioners. In addition, the heating capacity of the compressor capacity 1 control circuit and the indoor fan air volume control circuit is controlled in stages until the air conditioner stops operating. It is possible to reliably expand the operating limits during operation.

Furthermore, since a current transformer is not used, power can be turned on from either the outdoor unit or the indoor unit, and the power source can be turned on freely.

<Example> Hereinafter, an example of the present invention will be described in detail based on the drawings from FIG. 2 onwards.

FIG. 2 shows a refrigerant circuit of an air conditioner 11 (A) according to an embodiment of the present invention, in which (1) is an outdoor unit, (20) is an indoor unit, and both of these units (1), (20>
are connected by a liquid communication pipe (30) and a gas communication pipe (31). The outdoor unit (1) consists of a compressor (2), a four-way switching valve (SV+), and an outdoor heat exchanger (3).
) and an outdoor fan (Fl), and the discharge boat (2b) of the cylinder (2a) of the compressor (2) is equipped with a four-way switching valve (
The suction boat (2C) of the cylinder (2a) and the suction boat (2C) of the cylinder (2a) are communicated with the same discharge boat via the accumulator (4), respectively. The above four-way switching valve (SV
+) One of the incoming and outgoing boats is connected to the above outdoor heat exchanger (3).
, Ki (7 bilar tubes (5), (5), ..., connected to the liquid communication pipe (30) via a dryer (6), a gas-liquid separator (7) and a liquid shutoff valve (8), On the other hand, the other in/out boat is connected to the gas communication pipe (31) via a gas shutoff valve (9).

On the other hand, the indoor unit I-(20) has an indoor heat exchanger (
21) and an indoor fan (F2), the indoor heat exchanger (21) is directly connected to the upper liquid distribution connection pipe (30) and the gas communication pipe 31), and is equipped with a four-way switching valve (SV
When power is applied to ), the refrigerant flows in the direction of the solid arrow in the figure, condenses in the outdoor heat exchanger (3), and then evaporates in the indoor heat exchanger (21) after passing through the IC, thereby performing cooling operation.
When the four-way switching valve (SWI) is de-energized, the refrigerant flows in the direction of the dashed arrow in the figure, condenses in the indoor heat exchanger (21), and then evaporates in the outdoor heat exchanger (3). , Ifi cell operation is performed.

The compressor (2) is equipped with a gas injection boat (2e) in its cylinder (2a) that is opened and closed by a capacity control valve (2d), and the gas injection boat (2e) has an injection control valve (2e) that is opened and closed by a capacity control valve (2d). The gas-liquid separator (7) is connected to the gas-liquid separator (7) via a gas injection bypass pipe (11) with a gas injection bypass pipe (11) and a filter (10). A capacity control valve (S) is connected between the gas injection bypass piping (11) on the machine (2) side and the accumulator (4).
V3') are connected by refrigerant piping,
During cooling, close the injection control valve (SV2) and listen to the capacity control valve (SV3) to perform C cooling operation.
When performing capacity save operation during heating, both control valves (SV
2), (SV3) is closed to perform heating operation, and when performing capacity-up operation, the injection control valve (SV3) is closed.
Listening to SV2, the capacity control valve (SV3) is closed and the intermediate pressure gas separated by the gas-liquid separator (7) is injected into the compressor (2). The capacity of the plant is increased to allow for increased capacity operation.

In addition, Fig. 3 shows the compressor (2) of the outdoor units 1 to (1) above.
), outdoor fan (P+), four-way switching valve <SWI>ij, two-way control valve (SV2), <SV3), and an electric circuit for energizing the indoor fan (F2) of the indoor unit (20). , the outdoor unit (1) has the first to
Five fifth connection terminals ("I) to (V) are provided. Between the first connection terminal (1) and the fifth connection terminal (V), a compressor (2) and an outdoor A fan (Fl) is connected in parallel, and a second connection terminal (IF) and a fifth connection terminal (V
) and a four-way switching valve (SWI) and
1 valve (SV3) is connected in parallel, and the 4th connection terminal (I
An injection control valve (SV2') is connected between the fifth connection terminal (V) and the fifth connection terminal (V). Also, the third
When the connection terminal (1) and the fifth connection terminal (V) are connected to each other, the connection terminal (1) and the fifth connection terminal (V) are turned ON by supplying electricity, and the compressor (2) and the outdoor fan (2) are turned on.
An electromagnetic switch (MS) is connected to energize P+).

On the other hand, the indoor unit h (20) has the above outdoor unit (1
), five connection terminals (1> to (V)) connected correspondingly to the first to fifth connection terminals (1) to (V) are installed, and the first connection terminal (1) and A power supply voltage is applied between the fifth connection terminal <V>.In addition, the indoor units (20 units) are connected to each other.
'(P+) and a control unit h (F2), and the remote control unit 1-(P+) has manual switches (SWI) for operation, operation mode switching, dry keep, and wind ffi VJJ%. ) ~ (SW4) and m IJJ i
T! ! There is a manual volume (VR) for the verses,
The three fixed contacts of the air volume selector switch (SWa) are connected to the rapid, strong wind, and light wind terminals ()-1), (IVH, (L)) of the indoor fan (F2), respectively. The fifth connection terminal (V) is connected to the remaining terminals of the fan (F2).
2) includes the first to fifth relay solenoids (MR81) to (
The first to
Fifth relay contacts (MRCl) to (IvlRC5) are provided, and the first relay contact (MRCl) is connected to the movable contact of the air volume switching switch (SWa) of the remote control unit (Pl) and the first connection terminal <1). The indoor fan (F2) is operated by the closing operation of the first relay contact (MRCI).

In addition, the second relay contact (MRC2) is connected to the first connection terminal (1
) and the second connection terminal (■), and the opening operation of the second relay contact (MRC2) energizes the four-way switching valve (SWI) and the capacity control valve (SV3). ing. The third relay contact (MRC3) is the first
Connected between the connection terminal (1) and the third connection terminal (III), the closing operation of the third relay contact (MRC3) energizes the electromagnetic switch (MS) to turn on the compressor (2).
) and the outdoor fan (Fl). The fourth relay contact (MRC4) is connected to the third connection terminal (Il
l) and the fourth connection terminal (IV),
State 1 where the third relay contact (M'RC3) is closed
That is, the injection control valve (SV2) is energized by the closing operation of the fourth relay contact (MRC4) while the compressor (2) and the outdoor fan (Fl) are operating. Furthermore, the fifth relay contact (MRC5
) is connected between the light breeze fixed contact of the wind volume changeover switch (SWa) and the light breeze terminal (L) of the indoor fan (F2), and the movable contact of the wind volume changeover switch (SWa) is connected between the light breeze By operating the fifth relay contact (MRC5) while the fixed contact is switched to the strong wind terminal (M) of the indoor fan (F2), the light wind fixed contact of the wind switch (SW4) is switched to the strong wind terminal (M) of the indoor fan (F2). I am trying to make a switching connection.

Furthermore, the internal configuration of the control unit (F2) is shown in FIG. (SWl>) and a temperature control volume (VR) to select a signal, and the key matrix (40) is connected to a microcomputer via a key input interface (41) and a key scan interface (42). Also, (43) is a room temperature sensor consisting of a thermistor that is installed in the remote control unit (Pl) and detects the indoor temperature, and this sensor (43) is connected to the temperature control interface (44).
), a ladder circuit (45), and a heating/cooling switching circuit (46), which are input/output connected to a microcomputer (CP'tJ). Furthermore, (47) is a condensation temperature sensor consisting of a thermistor that detects the condensation temperature (T) of the refrigerant condensed in the indoor heat exchanger (3) during heating; A cold air prevention sensor used for temperature measurement to prevent cold air from blowing out from the unit (20) and an indoor heat exchanger (21) during cooling.
It also serves as an anti-freeze sensor used for temperature measurement to prevent frost buildup, and also has a peak cut interface (4B>) and a cold air/anti-freeze interface (49).
It is input/output connected to a microcomputer (CPU) via the cooling/heating switching circuit (46).

On the other hand, the output of the microcomputer (CPU) is input to the relay drive interface (50), and the output of the relay drive interface (50) is
It is connected to the ~fifth relay solenoid (MR8I) ~ (MR85) and is also input to the display drive interface (51). The output of the microcomputer (CPU) is also input to the display drive interface (51), and the output of the display drive interface (51) is connected to a light emitting diode (LED) for display. However, microcomputer (CP)
U ), during heating, the condensing temperature m u 1 no (47)
The fourth relay solenoid (M
J: A compressor capacity control circuit (
6O) and the fifth relay solenoid (MR8
5) Indoor fan (F2) that controls energization to increase the air volume of the indoor fan (F2) from a small air volume to a large air volume as the condensation temperature (T) of the refrigerant increases. Ifft control circuit (61) is configured.

Next, the control during heating in the above embodiment will be explained with reference to the flowchart shown in FIG. 1. A determination is made as to whether the temperature is higher than the set temperature (TO), and if the determination is No, the first relay solenoid (MR3I) is turned off and the indoor fan (F2) is kept in a stopped state. Return to first step. On the other hand, when the above determination is YES, the first relay solenoid (MR81) is turned ON, and the indoor fan (F2) is operated while maintaining the air flow corresponding to the switching position of the air volume switching switch (SW4).

After this, the above-mentioned coagulation temperature (temperature) is set to the above-mentioned first setting temperature (temperature).
The second set temperature (TA) higher than 1 (Tc) ((TA>
>('T-c)) is exceeded, and if this determination is NO, Il! It is assumed that the cell is not being operated in an overloaded state, and the process returns to the first step. On the other hand, when the determination is YES, it is assumed that the heating operation is being performed in an overload state, and peak cut control is performed.

In this peak cut control, the first and second timers first start counting, and the count time of the first timer (t
When A) is less than 8 seconds, return to the first step. On the other hand, the count time of the first timer (t A )
1, that is, if the time exceeding the second setting (1°A) of the condensing temperature (T) of the refrigerant continues for more than 8 seconds, the fourth relay solenoid (MR84
) is turned off, the capacity of the compression m(2> is forcibly lowered, and as a result, the heating capacity of the air conditioner elf(A>) is reduced.

After this, a first determination is made as to whether or not the count time (ts) of the second timer has elapsed for 8 minutes or more, and if this determination is YES, the refrigerant condensation temperature (1-) is determined.
A determination is made as to whether or not the temperature has decreased below the first set temperature (1"C), and the determination is N.

When , the fourth relay solenoid (MR84) is turned OFF to maintain the capacity reduction of the compressor (2) until the result is YES, and when the result is YES, the first relay solenoid (MR81) is turned OFF, and After the fourth relay solenoid (MR84) is turned ON and the peak cut control is canceled, the process returns to the first step.

On the other hand, the count time (te) of the second timer for the first time
If the judgment is No, the condensing temperature (-") is higher than the second stage constant temperature (TA), the third set temperature leak (TB) (
It is determined whether (TB)>(TA)) is exceeded, and if this determination is NO, the process returns to the first step. When the determination is YES, the fifth relay solenoid (MR85) is turned ON and the indoor fan (F
2), when the air is being blown in a light wind state, it is forcibly switched to a strong wind state, thereby increasing the amount of heat dissipation and lowering the first set temperature (Tc).

After this, - the count time (tB) of the second timer is 8
A second determination is made as to whether or not more than a minute has elapsed, and if this determination is YES, a determination is made as to whether the condensation temperature (T) of the refrigerant has fallen below the first set temperature (Tc). When the determination is No, the fifth relay solenoid (MR85) is turned on and the indoor fan (F2) is kept in a strong air condition until the determination is YES, and when the determination is YES, the first and fifth relay solenoid are turned on. (MR81
), (MR85) are turned off, and the fourth relay solenoid (MR84) is turned on to cancel the peak cut control, and then the process returns to the first step.

On the other hand, the second timer count time (ts) for the second time
When the determination is No, the condensing temperature (T) is set to a fourth set temperature (Ts) higher than the third set temperature (T'B).
A determination is made as to whether or not ((Ts)>(1-s >>) is exceeded, and this determination is N.

If so, simply return to the first step.

When the determination is YES, the third relay solenoid (M
R83) is turned OFF, and the operation of the compressor (2) and the outdoor fan (Fl) is stopped.

After that, in the same way as above, the count time of the second timer (
A third judgment is made as to whether or not tB) has elapsed for 8 minutes or more, and if this judgment is No, the compression t1M<2> and the outdoor fan (1τ1) are held in a stopped state until YES. . When the determination is YES, it is determined whether the refrigerant condensation temperature (T) is higher than the first set temperature (Tc), and when this determination is No, the compressor (2) and the outdoor fan (Fl ) is held in a stopped state and YES, the first and fifth relay solenoids (MR8I) and (MR85) operate OFF, and the third and fourth relay solenoids (MR83) and (MR8
4) is turned ON and the peak cut 1~ control is released, the process returns to the first step, and one cycle of the C control is completed.

Therefore, in this case, the overload state during heating operation is detected based on the condensation temperature (T) of the refrigerant, and the condensation humidity 1 of the refrigerant is detected.
The condensation temperature sensor (47), which detects Detection can be performed without using an expensive current transformer as in the past, and therefore the peak cut mechanism can be reduced to 19 at low cost.

In addition, as described above, the capacity of the compressor (2) is reduced by the time the refrigerant condensation temperature (1-) reaches the fourth set temperature (Ts) and the operation of the C air conditioner <A> is substantially stopped. Since the heating capacity of the air conditioner and the indoor fan (F2) are switched in sequence to gradually reduce the heating capacity, the operating limit of the air conditioner during heating can be reliably expanded.

Furthermore, since the overload condition during heating is detected based on the condensation temperature (-r) of the refrigerant, the air conditioner (A)
Power can be turned on from either the outdoor unit (1) or the indoor unit (2O), and there are no restrictions like when using a current transformer.

[Brief explanation of drawings]

Fig. 1 is an overall configuration diagram of the present invention, Figs. 2 to 5 show embodiments of the present invention, Fig. 2 is a refrigerant circuit diagram of Air Conditioner III, Fig. 3 is an electrical wiring diagram of the same, and Fig. 4 The figure is a block diagram of the control device, and FIG. 5 is a flowchart 1 to 1 of the same. (A)...Air conditioner, (1)...Outdoor unit,
(SV+)... Four-way switching valve, (3)... Outdoor heat exchanger, (Fl)... Outdoor fan, (7>... Gas-liquid separator, (SV2)... Injection Control valve, (
11)...Cass injection bypass piping, (S
, V3)...capacity control valve, (2O)...indoor unit, (21)...indoor heat exchanger, (F2)...indoor fan, (4O)...keema] helix , (CP
U)... Microcomputer, (43)... Room temperature sensor, (47>... Condensation temperature sensor, (60)...
- Compressor capacity control circuit, (61)... Indoor fan air volume control circuit. Continuing from page 1 @ Inventor Hideo Nomura 100 Hatachi-2, Oya, Oyamoto-cho, Kusatsu City, Shiga Plant, Daikin Industries, Ltd.

Claims (1)

[Claims] (1) A condensing temperature sensor (47) that detects the condensing temperature (T) of the refrigerant during heating, blocks the output signal from the condensing temperature sensor (47) and reduces the capacity of the compressor (2) to condense the refrigerant. The indoor fan (F2) is controlled based on the output signal from the condensing temperature sensor (47) and the compressor capacity control circuit (60), which controls the temperature (T) to decrease as the temperature (T) increases.
) An air conditioner comprising an indoor fan air volume control circuit (61) that controls the Asahikawa air flow rate so that the condensation temperature (T) of the refrigerant increases.