JPH0814701A - Air conditioner - Google Patents

Abstract

PURPOSE:To provide an air conditioner in which the erroneous action of a two-way valve is controlled to as low as possible by restricting the number of rotations of a compressor when the operation of the compressor is resumed, thereby improving the function and reliability of the compressor. CONSTITUTION:A refrigerating cycle is constituted by connecting a capability-variable compressor 1, an outdoor heat exchanger 2, a pressure-reducing main mechanism 3 for the cycle, an indoor heat exchanger 4 and the like to one another. The indoor heat exchanger 4 for the refrigerating cycle is divided into two units, and a pressure- reducing sub-mechanism 6 for reheating and a two-way valve 5 are connected in parallel with each other between the divided units. The two-way valve 5 is opened during cooling operation and closed during dehumidifying operation. In an air conditioner with this dehumidifying function, when erroneous action wherein the two-way valve 5 is closed during cooling operation occurs, the compressor 1 is stopped to return the two-way valve 5 to an open condition, and the compressor 1 is made to resume its operation after the refrigerating cycle is put into a balanced condition. Further, a controlling means 11 is provided, which restricts the operational capability of the compressor 1 at the time of the resumption of operation to capability lower than its operational capability at a point of time when the erroneous action of closing the two-way valve 5 has occurred.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cycle dry type air conditioner in which an outdoor heat exchanger is divided.

[0002]

2. Description of the Related Art Conventionally, in a cycle dry refrigeration cycle in which an indoor heat exchanger is divided into a cooler and a reheater, and a two-way valve and a pressure reducing mechanism are provided between them, a coil is energized as a two-way valve. The type that was sometimes closed was used.

In this case, during cooling / heating operation, de-energization is performed, the valve is opened, and during dehumidification operation, energization is performed and the valve is closed.

Here, for example, during the cooling operation, a phenomenon occurs in which the valve body is closed due to a pressure difference applied across the valve. That is, for example, when a large amount of the refrigerant flows, the refrigerant is sucked to the outlet side to create a negative pressure in the valve chamber, and the valve is pulled and closed.

When a malfunction of the valve such that the valve is closed occurs in this way, the compressor is stopped and restarted after the valve is closed.

[0006]

However, in the above method, the valve closing phenomenon occurs depending on the operating conditions of the air conditioner (room temperature, air temperature, rotation speed of the compressor) even if the operation is restarted. There is a risk of malfunctioning again, not only making air conditioning impossible but also causing equipment failure.

The present invention has been made in consideration of the above circumstances, and at the time of restarting, the malfunction of the two-way valve is minimized by limiting the rotational speed of the compressor to improve the function and reliability. The purpose is to provide an air conditioner.

[0008]

In order to achieve the above-mentioned object, the invention of claim 1 provides a variable capacity compressor, an outdoor heat exchanger,
A cycle main pressure reducing mechanism, an indoor heat exchanger, etc. are connected to form a refrigeration cycle, the indoor heat exchanger of the refrigeration cycle is divided, and a reheating auxiliary pressure reducing mechanism and a two-way valve are connected in parallel between them. In an air conditioner with a dehumidifying function that opens the two-way valve during the cooling operation and closes the two-way valve during the dehumidifying operation, when a malfunction that closes the two-way valve occurs during the cooling operation, the compressor is turned on. Stop and return the two-way valve to the open state,
After the refrigeration cycle is in a balanced state, the compressor is restarted and the operating capacity of the compressor at this restart is lower than the operating capacity at the time of the malfunction that closes the two-way valve. The air conditioner is provided with a control means for restricting the air conditioner.

According to a second aspect of the present invention, a temperature sensor is provided in the refrigerant pipe on the downstream side of the two-way valve, and the control means is
The air conditioner according to claim 1, further comprising means for inputting a detection value of the temperature sensor and detecting a malfunction of the two-way valve based on a temperature change thereof.

According to a third aspect of the present invention, a pressure sensor is provided in the refrigerant pipe on the downstream side of the two-way valve, and the control means is
The air conditioner according to claim 1, further comprising means for receiving a detection value of the pressure sensor and detecting a malfunction of the two-way valve based on a change in the pressure.

According to a fourth aspect of the present invention, a variable capacity compressor, a four-way valve, an outdoor heat exchanger, a cycle main pressure reducing mechanism, an indoor heat exchanger, etc. are connected to form a refrigeration cycle, and the indoor heat of the refrigeration cycle is formed. An air conditioner with a dehumidifying function, in which the exchanger is divided, the auxiliary decompression mechanism for reheating and the two-way valve are connected in parallel, and the two-way valve is opened during cooling operation and the two-way valve is closed during dehumidifying operation. In the heating operation, when a malfunction that closes the two-way valve occurs, the compressor is stopped and the two-way valve is returned to the open state, and after the refrigeration cycle reaches the balanced state, the compressor is turned on again. An air conditioner characterized by comprising control means for starting the operation and for limiting the operation capacity of the compressor at the time of restart to a capacity lower than the operation capacity at the time when the malfunction of closing the two-way valve occurs. It is a machine.

According to a fifth aspect of the present invention, a temperature sensor provided in the refrigerant pipe on the upstream side of the two-way valve during the heating operation is provided, the detection value of the temperature sensor is input, and the control means detects the temperature change. The air conditioner according to claim 4, further comprising means for detecting a malfunction of the one-way valve.

According to a sixth aspect of the present invention, the control means receives the detection value of the pressure sensor provided in the refrigerant pipe on the upstream side of the two-way valve during the heating operation, and detects the malfunction of the two-way valve by the change in the pressure. The air conditioner according to claim 4, which is configured to do so.

According to a seventh aspect of the present invention, there is provided a refrigerant heater for heating the refrigerant condensed in the indoor heat exchanger and returning the evaporative gas to the compressor during the heating operation, and the two-way valve is operated during the heating operation. The air conditioner according to claim 4, wherein when the malfunction occurs, the combustion of the refrigerant heater together with the compressor is stopped.

[0015]

According to the above construction, when the two-way valve malfunctions, when the compressor is stopped and then restarted, the capacity of the compressor is suppressed to operate, so that the malfunction occurs again after the restart. Can be prevented.

[0016]

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

FIG. 1 shows a schematic view of a refrigeration cycle of the present invention. In the figure, a compressor 1, an outdoor heat exchanger 2, a cycle main depressurizing mechanism 3 provided on the outdoor side, and an indoor heat exchanger 4 are sequentially connected. Then, the refrigeration cycle is formed.

The indoor heat exchanger 4 is divided into two, for example,
During cooling operation, the cooler 8 is provided on the upstream side and the reheater 7 is provided on the downstream side, and the two-way valve 5 and the indoor side reheating auxiliary decompression mechanism 6 are provided therebetween.
Are connected in parallel, and a temperature sensor 9 (or a pressure sensor (not shown)) may be attached to the refrigerant pipe 12a on the downstream side of the parallel circuit 12.

The detection value of the temperature sensor 9 is the control means 11
The control means 11 controls the opening / closing of the two-way valve 5 and also controls the compressor 1 via the rotation speed controller 10 such as an inverter so that the compressor 1 has a variable compression capacity.

As shown in FIG. 2, the two-way valve 5 has a valve box 13 having an inlet port 13a connected to the cooler 8 side and an outlet 13 port b connected to the reheater 7 side.
The electromagnetic solenoid 14 is mounted on the valve body, and the valve body 15 operated by the excitation / non-excitation of the electromagnetic solenoid 14 is a valve box 13
The valve body 15 is held at a position apart from the outlet port 13b by a spring (not shown) force as shown in the figure when not excited, and when not excited, Body 1
5 is seated on the outlet port 13b side and closed.

Next, the operation of the embodiment will be described.

First, during the cooling operation, the control means 11 keeps the electromagnetic solenoid 14 of the two-way valve 5 in a non-excited state, and keeps the valve body 15 in an open state as shown in FIG. .

The high-temperature high-pressure refrigerant from the compressor 1 flows to the outdoor heat exchanger 2, is condensed there, is depressurized by the main depressurizing mechanism 3, and then passes through the cooler 8 of the outdoor heat exchanger 4 to be a two-way valve. It flows to the reheater 7 via 5 and is vaporized and then returns to the compressor 1.

During this cooling operation, the control means 11 adjusts the capacity of the compressor 1 via the rotation adjuster 10 according to the air conditioning load (not shown) determined by the difference between the set temperature and the room temperature. It has become.

During this cooling operation, if the valve body 15 of the two-way valve 5 closes erroneously due to the pressure balance before and after it, the refrigerant in the cooler 8 flows through the auxiliary pressure reducing mechanism 6 to the reheater 7, so that Its temperature is lower than that flowing through the one-way valve 5.
Therefore, the temperature sensor 9 downstream thereof detects the refrigerant temperature, and the control means 11 recognizes from the change in the temperature detected by the temperature sensor 9 that the two-way valve 5 has closed due to a malfunction, and stops the compressor 1 as well as before and after. The compressor 1 is released from the stop and restarted after waiting for the pressure to balance. At this time, the control means 11 stores the maximum rotation speed of the compressor 1 at the time of malfunction, and starts the compressor 1 at a rotation speed one step lower than the maximum rotation speed at the time of restart.

FIG. 3 shows a control flow chart of the control means 11. In the rotation speed control routine during the cooling operation, it is first judged whether or not the detected value Tc1 of the temperature sensor 9 is larger than the set value Tc (step 1). ), Next, it is determined whether or not a predetermined time has passed (step 2), and if the predetermined time has passed (yes), the compressor 1 is stopped.
Next, determine whether the balance time has elapsed (step
3) Then, when the time to balance the cycle has passed,
The stop release (restart) of the compressor 1 is performed at a rotation speed that is one step less than the maximum rotation speed of the compressor when the malfunction occurs, and the operation returns to the rotation speed control routine.

As described above, when the compressor is restarted, the maximum rotation speed of the compressor is suppressed to be lower than that at the time of malfunction, so that malfunction does not occur again, and (1) the air conditioning malfunction state continues. Therefore, there is an effect that the performance of the device can be improved, (2) the deterioration of the device due to repeated ON / OFF can be suppressed, and the reliability can be improved.

In the above embodiment, the temperature sensor 9 detects the malfunction of the two-way valve 5, but a pressure sensor is provided on the low pressure side, and the control means 11 operates based on the abnormal pressure of the pressure sensor. It may be configured to detect.

During the cycle dry type dehumidifying operation, the control means 11 closes the two-way valve 5 and the compressor 1
The refrigerant from the compressor 1 passes through the outdoor heat exchanger 2 and is depressurized by the main depressurization mechanism 3, and then enters the cooler 8 of the indoor heat exchanger 4 to cool the indoor air there. Dehumidification is performed, the pressure is further reduced by the auxiliary pressure reduction mechanism 6, evaporated by the reheater 7, and returned to the compressor 1. In this case, the indoor heat exchanger 4 is divided, and the sub decompression mechanism 6 is provided between them to perform the dehumidifying operation, so that the efficient dehumidifying operation can be performed without reducing the indoor temperature as much as possible.

Next, a concrete embodiment will be described with reference to FIG.

In the description of FIG. 1, a basic cooling cycle of the present invention is shown for the sake of convenience of explanation, but in FIG. 4, an actual heat pump cycle and a refrigerant heating type air conditioner are shown.

In the figure, first, in the indoor unit UI,
The indoor heat exchanger 24 is divided into a cooler 28 and a reheater 27, and an auxiliary pressure reducing mechanism 26 and a two-way valve 25 are provided between them to connect the pipe 2
Connected by 3.

A compressor 21 is provided in the outdoor unit UO, and a four-way valve 31, an outdoor heat exchanger 22, and a compressor 21 are provided from the discharge side.
The refrigerant heater 32, the main decompression mechanism 33 such as an expansion valve, and the muffler 34 are connected, and the packed valve 35 connects the connecting pipe 36.
Is connected to the cooler 28 side of the indoor unit UI via
On the suction side, the four-way valve 31, the strainer 32, and the packed valve 37 are connected via the connecting pipe 38 to the indoor unit UI.
Is connected to the reheater 27 side.

Reference numeral 39 denotes the refrigerant heater 32 during the heating operation.
Return line for returning the refrigerant evaporated by the burner heating to the suction side of the compressor 21, 40 is a two-way valve connected to the line, 41 is an accumulator connected to the suction side of the compressor, and 42 is a heating operation. A line for directly supplying the refrigerant to the refrigerant heater 32 at the start of, a 43 is a capillary tube connected to the line 42, and 44 is a heating operation,
The refrigerant heater 3 is provided in order to secure the refrigerant circulation amount of the compressor 21.
The hot gas bypass lines, TD, TS, TEI, and TEO, which circulate to the compressor 21 via 2, are refrigerant temperature sensors, respectively.

In the heat pump cycle using the four-way valve 31 and the refrigerant heater 32, the flow of the refrigerant during the cooling operation is as shown by the solid arrow in the figure, and during the heating operation, the dotted arrow in the figure is shown. The refrigerant flows as indicated by.

The control by the malfunction of the two-way valve 25 during the cooling operation is the same as that of the embodiment of FIG. 1, but if the malfunction occurs during the heating operation, the auxiliary heat reducing mechanism from the reheater 27 to the cooler 28 is operated. Since the refrigerant flows through the temperature sensor 26, the temperature sensor 29
Since the detected value of is higher than the set condensing temperature of the heating operation, the control means detects the malfunction.
Further, the control after the detection is the same as in the cooling operation, that is, the compressor 2
1 is stopped, and the compressor 21 is restarted with a capacity lower than the capacity up to that point after the time when the cycle is balanced.

Further, the detection of this malfunction may be detected by a pressure change as in the embodiment of FIG.

FIG. 5 shows another embodiment of the present invention. The basic structure is the same as that of the embodiment of FIG. 4, but a circuit 52 for connecting the cooler 28 and the reheater 27 is provided. It shows a modified example. In the embodiment of FIGS. 1 and 4, the circuits 13 and 23 have been described as the pressure reducing mechanism and the two-way valve. However, the two-way valve and the pressure reducing mechanism are integrated into the rapid opening type electronic expansion valve 54. It has both functions. Further, the temperature detection is configured to detect using two temperature sensors 29a and 29b.

Also in the case of the embodiment shown in FIG. 5, when the sudden opening type electronic expansion valve 54 malfunctions due to pressure balance, it is possible to stably operate the cycle by performing the same control as described above. .

[0040]

In summary, according to the present invention, when the two-way valve malfunctions, when the compressor is stopped and then restarted, the capacity of the compressor is suppressed and the compressor is operated. It is possible to prevent the occurrence of a malfunction again.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of the present invention.

FIG. 2 is a detailed cross-sectional view of the two-way valve of FIG.

FIG. 3 is a diagram showing a flowchart of control means of the present invention.

FIG. 4 is a diagram showing a more specific embodiment of the present invention.

FIG. 5 is a diagram showing a modification of FIG.

[Explanation of symbols]

 1 compressor 2 outdoor heat exchanger 3 main decompression mechanism 4 indoor heat exchanger 5 two-way valve 6 auxiliary decompression mechanism 7 reheater 8 cooler 9 temperature sensor 11 control means

Claims (7)

[Claims] 1. A refrigeration cycle is formed by connecting a variable capacity compressor, an outdoor heat exchanger, a main depressurizing mechanism for a cycle, an indoor heat exchanger, etc., and the indoor heat exchanger of the refrigeration cycle is divided between them. The reheating sub pressure reducing mechanism and the two-way valve are connected in parallel,
In an air conditioner with a dehumidifying function that opens the two-way valve during cooling operation and closes the two-way valve during dehumidifying operation, when a malfunction that closes the two-way valve occurs during cooling operation, the compressor is turned on. After stopping and returning the two-way valve to the open state, and after the refrigeration cycle is in a balanced state, the compressor is restarted and the operating capacity of the compressor during this restart is
An air conditioner comprising control means for limiting the operating capacity to a level lower than the operating capacity at the time when the malfunction of closing the two-way valve occurs. 2. A temperature sensor provided in a refrigerant pipe on the downstream side of the two-way valve, wherein the control means inputs a detection value of the temperature sensor and detects a malfunction of the two-way valve based on a temperature change thereof. The air conditioner according to claim 1, further comprising means. 3. A pressure sensor provided in a refrigerant pipe on the downstream side of the two-way valve, wherein the control means inputs a detection value of the pressure sensor and detects a malfunction of the two-way valve based on a change in the pressure. The air conditioner according to claim 1, further comprising means. 4. A refrigeration cycle is formed by connecting a variable capacity compressor, a four-way valve, an outdoor heat exchanger, a cycle main pressure reducing mechanism, an indoor heat exchanger, etc., and dividing the indoor heat exchanger of the refrigeration cycle. , In the meantime, the auxiliary decompression mechanism for reheating and the two-way valve are connected in parallel, the two-way valve is opened during the cooling operation, and the two-way valve is closed during the dehumidifying operation. , When the malfunction of closing the two-way valve occurs, the compressor is stopped and the two-way valve is returned to the open state, and after the refrigeration cycle reaches the balanced state, the compressor is restarted and An air conditioner comprising control means for limiting the operating capacity of the compressor at the time of re-operation to a capacity lower than the operating capacity at the time of the malfunction in which the two-way valve closes. 5. A temperature sensor provided in the refrigerant pipe upstream of the two-way valve during heating operation is provided, and a detection value of this temperature sensor is input, and the control means causes a malfunction of the two-way valve due to this temperature change. The air conditioner according to claim 4, further comprising a detecting unit. 6. A pressure sensor provided in the refrigerant pipe upstream of the two-way valve during heating operation, wherein the control means inputs the detection value of the pressure sensor, and the pressure change causes malfunction of the two-way valve. The air conditioner according to claim 4, further comprising a detecting unit. 7. A heating device has a refrigerant heater for heating the refrigerant condensed in the indoor heat exchanger and returning the evaporative gas to the compressor during heating operation, and when the two-way valve malfunctions during heating operation, The air conditioner according to claim 4, wherein combustion of the refrigerant heater is stopped together with the compressor.