JP3170507B2 - Air conditioning equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for cooling and heating air-conditioning zones such as a plurality of rooms of a building individually in an optimum state. The present invention relates to a multi-type direct expansion type air conditioner connected via an air conditioner.

[0002]

2. Description of the Related Art Conventionally, there is a so-called multi-type direct expansion type air conditioner in which a plurality of indoor units are connected to one outdoor unit via a refrigerant pipe. This type of air conditioning equipment can switch between cooling and heating mode operations. In each of the indoor units of this type of air-conditioning equipment, the amount of air blown and the amount of refrigerant flow are substantially proportional to 3 to 4 during operation in both the cooling and heating modes.
It is set to the step control mode. By comparing the suction temperature of each indoor unit with the temperature of the air conditioning zone, or comparing the suction temperature and the blow-out temperature of the indoor unit, each indoor unit is operated by selecting from a plurality of control modes. . On the other hand, one of the outdoor units connected to each of these indoor units via a refrigerant pipe is also initially set to a multi-step control mode, and is appropriately set to a multi-step control mode according to the stepwise control mode operation of each of the indoor units. The operation mode is selected from among the above control modes to ensure the required total refrigerant flow rate in each indoor unit.

[0003]

However, in such a conventional multi-type direct expansion type air conditioner, the air flow rate and the refrigerant flow rate of each indoor unit can be set only in a multi-step control mode. It is difficult to provide detailed and optimal air conditioning in the air conditioning zone, and the operation control of the outdoor unit is performed in multiple stages, resulting in a large amount of waste in the refrigerant discharge capacity of the compressor, inefficiency, bulky power consumption, and uneconomical. .

Further, each indoor unit of the conventional multi-type direct expansion type air conditioner described above can supply air only to one air conditioning zone or an air conditioning zone having approximately the same load. In addition, each of the indoor units does not supply air to a plurality of different air-conditioning zones that satisfy various conditions at the same time.

[0005] In other words, a zone having a large air conditioning load and requiring a maximum air volume and a zone having a small air conditioning load and requiring a minimum air volume are simultaneously present in a plurality of air conditioning zones. The combination of these air conditioning zones under different load conditions is endless, and it is necessary to simultaneously supply satisfactory air from these indoor units to the various air conditioning zones. However, as described above, if the air flow rate and the refrigerant flow rate of the indoor unit can be set only in a multi-step control mode, it is very difficult to simultaneously supply various air conditioning zones with satisfactory air supply. Not only is it not possible to perform a fine-tuned optimal air conditioning of the zone, but also the waste of the capacity of the outdoor unit is further increased, resulting in inefficiency and an increase in power consumption.

The present invention has been made in view of the above circumstances,
The purpose of this is to make it possible to air condition the air-conditioning zone assigned to each indoor unit in a fine and optimal state, and to operate the outdoor unit with little waste and efficient, and to save money. An object of the present invention is to provide an inflatable air conditioner.

According to a second object, in addition to the first object, a multi-type direct expansion type air conditioner in which each indoor unit can simultaneously and finely air-condition a plurality of air-conditioning zones having different air-conditioning loads in an optimal state. To provide facilities.

A third object is to provide, in addition to the above objects, a multi-type direct expansion type air conditioner capable of air-conditioning the air-conditioning zone assigned to each indoor unit in an even more optimal state. .

A fourth object is that, in addition to the above objects, even if the cooling / heating mode operation is mixed in a plurality of indoor units, one outdoor unit can efficiently cope with it.
Moreover, it is an object of the present invention to provide a multi-type direct expansion type air conditioner which is extremely efficient and economical in which the operation of the outdoor unit is not wasted, is extremely efficient, and the cost is greatly reduced.

[0010]

In order to achieve the first object, the air conditioner according to the first aspect of the present invention is configured such that-outdoor units are connected to the outdoor units via refrigerant pipes, respectively. In a multi-type direct expansion type air conditioner including a plurality of indoor units each capable of blowing air to a predetermined air conditioning zone, each indoor unit needs to correspond to the air conditioning load of the air conditioning zone assigned to each of the indoor units. The air volume of the blower is controlled on the basis of the air volume, and the air volume which is sent to the heat exchanger by the air blower and which actually passes through the heat exchanger, the suction side temperature and the blow side temperature is detected, and the suction side is detected. It calculates the difference between the set air temperature of the temperature and the heat exchanger required amount of heat exchange of the heat exchanger from the air volume, to determine the required coolant flow rate of the heat exchanger commensurate to control the refrigerant flow rate adjusting valve 且The setting balloon and the balloon-side temperature
On the other hand, the outdoor unit has a controller that corrects the required refrigerant flow rate based on the difference from the temperature, while the outdoor unit determines the total refrigerant flow rate based on the required refrigerant flow rate information from the controller of each indoor unit. And a control device for controlling the discharge capacity of the compressor and the refrigerant flow control valve.

[0011] With this, the air volume and the refrigerant flow rate of each indoor unit are not controlled stepwise as in the conventional case, but instead.
Since the air volume and the refrigerant flow rate are always controlled according to the air conditioning load of the air conditioning zone assigned to each air conditioning zone, the air conditioning from each indoor unit can be finely and optimally air-conditioned in each air conditioning zone. Also, the outdoor unit determines the total refrigerant flow rate based on the required refrigerant flow rate information from the control unit of each indoor unit, and controls the discharge capacity of the compressor and the refrigerant flow regulating valve. The operation is efficient with less waste, and costs can be reduced.

According to a second aspect of the present invention, an air conditioner is provided, in addition to the configuration of the first aspect, in order to achieve the second aspect.
Each indoor unit is connected to a plurality of air conditioning zones so as to be able to blow air through a terminal air volume control unit, and the control device of each indoor unit needs to correspond to the air conditioning load of each of the plurality of air conditioning zones. It is characterized in that the air volume command is received from the terminal air volume control unit, the required air volume of the sum total thereof is calculated, and the air volume of the blower is controlled. Thus, in addition to the above-described operation, each indoor unit can simultaneously and finely air-condition a plurality of air-conditioning zones having different air-conditioning loads in an optimal state.

In order to achieve the third object, the air conditioning equipment according to the third and fourth aspects of the present invention has, in addition to the structure of the first or second aspect, a control device for each indoor unit, wherein Detects the volume of air sent to the vessel and the temperature on the suction side,
And a detecting means for calculating a required heat exchange amount of the heat exchanger from the difference between the suction side temperature and the set blowout temperature of the heat exchanger and the air volume, and detecting a blowout side temperature of the heat exchanger. The required amount of exchanged heat of the heat exchanger is corrected from the difference between the actual outlet side temperature and the set outlet temperature, and the required refrigerant flow rate of the heat exchanger corresponding thereto is determined to control the refrigerant flow regulating valve. It is characterized by the following.

In this case, in addition to the above-mentioned operation, each indoor unit determines the air volume and the refrigerant flow rate according to the air-conditioning load of the air-conditioning zone assigned to each of the indoor units and sets the actual temperature on the blow-out side of the heat exchanger. Based on the difference from the blow-out temperature, the required exchange heat of the heat exchanger is corrected and accurate,
The refrigerant temperature is unstable, the refrigerant flow rate fluctuates,
Even if the humidity of the air changes, an optimum refrigerant flow rate can always be ensured, and the air-conditioning zones can be more finely and optimally air-conditioned by supplying air from the respective indoor units. Along with this, the discharge capacity of the compressor of the outdoor unit can be further reduced and a highly efficient operation can be performed.

According to a fifth aspect of the present invention, in order to achieve the fourth object, in addition to the configuration of any of the first to fourth aspects, the outdoor unit control device further comprises: Receiving the respective cooling / heating mode operation information and the respective required refrigerant flow rate information from the control device, and increasing the sum of the required refrigerant flow rate for the cooling mode operation and the total required refrigerant flow rate for the heating mode operation Determine the total required refrigerant flow rate of one of the operation modes and the operation mode of the larger one, perform switching control of the operation mode of the outdoor unit and control of the discharge capacity of the compressor corresponding to this, and refrigerant to the heat exchanger of the outdoor unit. It is characterized in that the flow rate is determined to be a flow rate corresponding to the difference between the two and the refrigerant flow control valve is controlled.

With this arrangement, in addition to the above-described operation, even if the cooling / heating mode operation is mixed in a plurality of indoor units, one outdoor unit can efficiently cope with the operation. The heat can be transferred between the indoor unit and the indoor unit in the mode operation, so that the load on the outdoor unit can be reduced, the operation is not wasted, and the operation is very efficient and the cost can be greatly reduced.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the multi-type direct expansion type air conditioner of the present invention will be described below with reference to the drawings.

First, FIG. 1 schematically shows the entire configuration. -An outdoor unit 1 for cooling and heating, and a refrigerant pipe 2
A plurality of indoor units 3 for cooling and heating connected via
Is provided. Each of the indoor units 3 is connected via a ventilation duct 4 to supply air to a plurality of air-conditioning zones 5 such as a room in a building.

Each of the air conditioning zones 5 is provided with a thermostat 6 for detecting and setting a room temperature. A terminal air volume control unit (VAV unit) 7 is provided in each of the branch ducts 4a of the ventilation duct 4 connected to each of the air conditioning zones 5. Each of the terminal air flow control units 7...
7 and receives an electric signal from the thermostat 6 and independently receives the air conditioning zone 5.
The required air volume corresponding to the air conditioning load is determined, and the damper and the like incorporated therein are adjusted in opening to control the supplied air volume.

In general, the air conditioning zones 5 have different sizes and air conditioning loads. For this purpose, the terminal air flow control units 7 are provided with different sizes (capacities) according to the designed air conditioning load for each air conditioning zone 5.

The outdoor unit 1 includes a compressor 1
0, a heat exchanger 11, a blower 12 for exchanging heat by passing outside air through the heat exchanger 11, and a control device 13 for each of these devices.

Each of the indoor units 3 is provided with a heat exchanger 31.
And a blower 32 that blows into the blower duct 4 while passing heat through the outside air or the like to the heat exchanger 31 and a control device 33 for each of these devices. This control device 33
Is a plurality of air conditioning zones 5 assigned to the indoor unit 3
The terminal has a function of receiving a required air volume command corresponding to the air conditioning load from each terminal air volume control unit 7 to control each device, and exchanging the information with the control device 13 of the outdoor unit 1.

More specifically, the outdoor unit 1 comprises:
As shown in FIG. 2, a wind tunnel 15 is provided, a heat exchanger 11 is disposed in the wind tunnel 15, and a blower 12 that sucks and ventilates outside air or the like to the heat exchanger 11 is provided with a heat exchanger 11. It is installed on the lee side. Further, a wind speed detector 16 for detecting the suction side air volume is installed on the windward side of the heat exchanger 11 in the wind tunnel 15, and a suction side temperature detector 17 is also installed on the windward side. An outlet-side temperature detector 18 is installed on the leeward side of the exchanger 11 , and detection signals from the detectors 16, 17, and 18 are sent to the control device 13.

The outdoor unit 1 has a built-in compressor 10, and a refrigerant pipe 2a discharged to the refrigerant discharge side of the compressor 10 is branched in two directions. One of the refrigerant pipes 2b is connected to the heat exchanger 11. The other refrigerant pipe 2c is connected to the electromagnetic valve 20a which is opened when it functions as a condenser, and extends toward the indoor units 3. An accumulator 21 is connected to the suction side of the compressor 10 by piping. Refrigerant piping 2 that has exited from the accumulator 21 to the side opposite to the compressor 10
d is branched in two directions, one refrigerant pipe 2e is connected to a solenoid valve 20b which is opened when the heat exchanger 11 acts as an evaporator, and the other refrigerant pipe 2f is connected to the indoor units 3. Has been extended to. The solenoid valves 20a, 2
Refrigerant pipes 2b and 2e provided with Ob are joined to one refrigerant pipe 2g at the tip and connected to one end of the heat exchanger 11. In the middle of the refrigerant pipe 2g, a pipe temperature detector 22 for detecting the temperature of the evaporated refrigerant flowing out when the heat exchanger 11 functions as an evaporator is attached, and the detection signal is also sent to the control device 13. Has become.

Furthermore, with the expansion valve 23 and the refrigerant flow rate adjusting valve 24 to the refrigerant pipe 2h exiting from the other end of the heat exchanger 11 are provided in order, effect the heat exchanger 11 as a condenser A pipe is provided for bypassing the expansion valve 23 during the operation, and a check valve 25 is provided in the middle of the pipe. A refrigerant tank 26 is provided at the tip of the refrigerant pipe 2h, and a refrigerant pipe 2i extends from the refrigerant tank 26 and extends toward the indoor units 3.

Each of the indoor units 3 is configured as shown in FIG. That is, the wind tunnel 35 is provided, and the wind tunnel 3
A heat exchanger 31 is arranged in the inside of the heat exchanger 5, and a blower 32 that feeds into the air duct 4 while sucking and passing outside air through the heat exchanger 31 to perform heat exchange is installed on the leeward side of the heat exchanger 31. Have been. Further, a wind speed detector 3 for detecting the air volume on the suction side on the windward side from the heat exchanger 31 in the wind tunnel 35.
6 and a suction-side temperature detector 3
7 is installed, and further, a blow-off temperature detector 38 is installed on the leeward side of the heat exchanger 31 in the wind tunnel 35, and detection signals of these detectors 36, 37, 38 are respectively transmitted to the control device 3.
3 to be sent.

A refrigerant pipe 2j extending from one end of the heat exchanger 31 is branched in two directions from the middle, and the heat exchanger 31 acts as a condenser (heating mode operation) on one of the refrigerant pipes 2k. Solenoid valve 40a that is opened when it is opened
Is provided, and the tip of the refrigerant pipe 2k extends toward the outdoor unit 1. The other refrigerant pipe 2m is provided with an electromagnetic valve 40b that is opened when the heat exchanger 31 is operated as an evaporator (cooling mode operation), and the tip of the refrigerant pipe 2m extends toward the outdoor unit 1. Has been issued. A pipe temperature detector 42 for detecting the temperature of the evaporated refrigerant when the heat exchanger 31 acts as an evaporator is attached in the middle of the refrigerant pipe 2j, and this detection signal is also sent to the controller 33. .

Further, an expansion valve 43 and a refrigerant flow regulating valve 44 are connected to a refrigerant pipe 2n extending from the other end of the air heat exchanger 31.
Are sequentially provided, and the tip of the refrigerant pipe 2n extends toward the outdoor unit 1. The refrigerant pipe 2n is provided with a pipe that bypasses the expansion valve 43 when the heat exchanger 31 functions as a condenser, and a check valve 45 is provided in the middle of the pipe.

As shown in FIG. 4, the refrigerant pipes 2n of the indoor units 3 are communicated with each other via a refrigerant pipe 2p, and in this state, the refrigerant pipes 2i extending from the outdoor unit 1 are connected. Is connected to Similarly, the refrigerant pipes 2k of the indoor units 3 are communicated with each other via the refrigerant pipes 2q. In this state, the refrigerant pipes 2k are connected to the refrigerant pipes 2c extending from the outdoor unit 1. Are connected to each other via a refrigerant pipe 2r, and are connected to a refrigerant pipe 2f extending from the outdoor unit 1 in this state.

Here, as shown in FIGS. 1 and 3, the control unit 33 of each indoor unit 3
Receives a required air volume command (excess or deficiency signal) corresponding to the air conditioning load of the plurality of air conditioning zones 5 from each terminal air volume control unit 7, calculates a required air volume of a total sum thereof, and controls the air volume of the blower 32. It has a function to perform This air volume control is performed by controlling the rotation speed of the blower 32 using an inverter.

In order to determine the required flow rate of the refrigerant corresponding to the flow rate of the indoor unit 3, the control device 33 first determines the flow rate of the air passed through the heat exchanger 31 based on a signal from the wind speed detector 36. calculate. That is, since the terminal air volume control units 7 in each of the air conditioning zones 5 independently control the air volume according to the air conditioning load, the pressure loss of the blower 32 changes, and the rotation speed of the blower 32 and the actual heat exchanger It does not always coincide with the air volume sent to 31. For this purpose, the heat exchanger 3 is detected by a detection signal from the wind speed detector 36.
1 is calculated as the air volume actually transmitted. At the same time, a detection signal from the suction side temperature detector 37 of the heat exchanger 31 is received, and a difference between the suction temperature to the heat exchanger 31 and a predetermined set outlet temperature is obtained. The required amount of exchange heat of the heat exchanger 31 is calculated from the above, the required amount of refrigerant flow to the heat exchanger 31 corresponding to the required amount of exchange heat is determined, and based on this, the refrigerant flow control valve 44 of the indoor unit 3 is opened. It has a function to control the degree.

At this time, a signal from a temperature detector 38 for detecting an actual blow-off temperature on the leeward side of the heat exchanger 31 is received, and a difference between the actual blow-out temperature and the set blow-out temperature is determined. Thus, it has a function of further correcting the calculated required heat exchange amount of the heat exchanger 31. A function is provided for accurately determining the required refrigerant flow rate to the heat exchanger 31 corresponding to the corrected required heat exchange quantity and for controlling the opening degree of the refrigerant flow rate adjustment valve 44 of the indoor unit 3 based on this. I have.

The reason for the correction of the required refrigerant flow rate is as follows.
Refrigerant is not always in a perfect liquid phase , but in most cases is a gas-liquid mixed phase, its temperature is unstable and constantly changes, and the heat quantity of the unit refrigerant quantity obtained from the theoretical refrigeration cycle does not match the actual quantity In many cases, the relationship between the opening degree of the flow control valve 44 and the flow rate is not constant. In addition, the heat exchanger 31 itself is not stable, and the difference in refrigerant temperature between the inlet side and the outlet side of the refrigerant also changes. In addition, the humidity of the air is not constant, and the required total heat varies according to the airflow and the temperature difference. For this reason, the flow rate of the refrigerant is corrected by feedback while detecting the temperature of the blow-out side that has actually passed through the heat exchanger 31.

Further, when operating the heat exchanger 31 of the indoor unit 3 as an evaporator (cooling mode), the control device 33 receives a signal from the pipe temperature detector 42 of the refrigerant pipe 2j and performs heat exchange. A function of indirectly detecting the evaporating temperature of the refrigerant in the heat exchanger 31 and controlling the opening of the expansion valve 43 so that the evaporating temperature becomes constant.

The control device 33 operates either manually or automatically in accordance with the air conditioning load of the plurality of air conditioning zones 5 that the indoor unit 3 is responsible for, and by opening and closing the electromagnetic valves 40a and 40b. It has a function of performing operation control between the cooling mode and the heating mode.

As shown in FIGS. 1 and 2, the controller 13 of the outdoor unit 1 receives the respective cooling / heating operation mode information and the required refrigerant flow rate information from the controller 33 of each of the indoor units 3. The operation mode of the outdoor unit 1 is switched and controlled based on the above, and the total required refrigerant flow rate is calculated and determined, and the refrigerant discharge capacity from the compressor 10 is controlled through the capacity control means of the compressor 10, and the refrigerant flow rate is controlled. It has a function of controlling the opening of the regulating valve 24.

That is, the control device 13 receives the respective cooling / heating operation mode information and the required refrigerant flow rate information from the control device 33 of each indoor unit 3.
Calculate and compare the total required refrigerant flow rate for the cooling mode operation and the total required refrigerant flow rate for the heating mode operation, and select the solenoid valve 20 so as to select the higher operation mode.
a, a function of performing open / close switching control of 20b. Further, while determining the total required refrigerant flow rate of the operation mode of the larger one and controlling the discharge capacity of the compressor 10 corresponding to this, the refrigerant flow rate to the heat exchanger 11 of the outdoor unit 1 is equivalent to the difference between the two. To set the flow rate
It has a function of controlling the opening of the refrigerant flow control valve 24.

Further, the control device 13 receives a detection signal from the suction side temperature detector 17 of the heat exchanger 11 and obtains a difference between the suction temperature to the heat exchanger 11 and a predetermined set temperature. Based on the information and the information on the flow rate of the refrigerant to the heat exchanger 11, a required air flow to the heat exchanger 11 is calculated, and based on the calculated air flow, the blower 12 is inverter-controlled to perform the air flow control.

At this time, since the rotational speed of the blower 12 does not always match the air volume actually sent to the heat exchanger 11, the actual air volume is calculated based on the detection signal from the wind speed detector 16 and the feedback is performed. Control, and for the same reason as described above, receives a signal from the temperature detector 18 for detecting the actual blow-off temperature on the leeward side of the heat exchanger 11, and obtains the difference between the actual blow-out temperature and the set temperature. Based on
There is provided a function of further correcting the required airflow and controlling the airflow of the blower 12.

Further, when operating the heat exchanger 11 of the outdoor unit 1 as an evaporator (heating mode), the control device 13 receives a signal from the pipe temperature detector 22 of the refrigerant pipe 2g, and A function of indirectly detecting the evaporation temperature of the refrigerant at 11 and controlling the opening of the expansion valve 23 so that the evaporation temperature is kept constant.

The operation of the multi-type direct expansion type air conditioner having the above-described configuration will be described. First, the terminal air volume control unit (VAV unit) 7 independently determines the required air volume corresponding to the air conditioning load based on the electric signal from the thermostat 6 of each air conditioning zone 5 and controls the opening degree. Is sent to the control device 33 of the indoor unit 3.

The controller 33 of each of the indoor units 3 receiving this command calculates the total sum of the required air volumes of the plurality of air conditioning zones 5... Which the indoor units 3 cover, and controls the air volume of the blower 32. .

At the same time, the control device 33 receives the detection signal from the wind speed detector 36, calculates the air volume to be sent to the heat exchanger 31, and
Receiving the detection signal from 7, the difference between the suction temperature into the heat exchanger 31 and the predetermined set blowing temperature is obtained, and the required exchange heat amount of the heat exchanger 31 is calculated from this difference and the air volume. At this time, a signal from the temperature detector 38 is received, an actual blow-side temperature on the leeward side of the heat exchanger 31 is detected, and based on a difference between this and the set blow-off temperature, the calculated heat exchanger The necessary exchange heat quantity of 31 is further corrected. Based on the corrected required heat exchange amount, the necessary refrigerant flow amount to the heat exchanger 31 corresponding to the corrected heat exchange amount is accurately determined, and based on this, the opening degree of the refrigerant flow adjustment valve 44 of the indoor unit 3 is controlled.

The control device 33 determines whether the air conditioner is in the cooling mode or the heating mode in accordance with the air conditioning load of the plurality of air conditioning zones 5 which the indoor unit 3 is responsible for. Perform opening and closing switching,
It is determined whether the heat exchanger 31 is operated as an evaporator (cooling mode) or a condenser (heating mode). When performing the cooling mode operation using the heat exchanger 31 as an evaporator, a signal is received from the pipe temperature detector 42 of the refrigerant pipe 2j, and the evaporation temperature of the refrigerant in the heat exchanger 31 is indirectly detected. Expansion valve 4 so that evaporation temperature is constant
3 is performed.

On the other hand, the controller 13 of the outdoor unit 1
The respective cooling and heating operation mode information and the required refrigerant flow rate information are received from the control device 33 of each of the indoor units 3..., And the total of the required refrigerant flow rate for the cooling mode operation and the total of the required refrigerant flow rate for the heating mode operation are calculated. Computation and comparison are performed, the operation mode of the larger one is selected, open / close switching control of the solenoid valves 20a and 20b is performed, and it is determined whether the heat exchanger 11 is operated as an evaporator or a condenser. The total required flow rate of the larger operation mode is determined, the discharge capacity of the compressor 10 is controlled in accordance with the determined total flow rate, and the flow rate of the refrigerant to the heat exchanger 11 of the outdoor unit 1 is equivalent to the difference between the two. The opening degree of the refrigerant flow control valve 24 is controlled so as to set the flow rate to be controlled.

Further, the control device 13 receives a detection signal from the suction side temperature detector 17 of the heat exchanger 11, and obtains a difference between the suction temperature into the heat exchanger 11 and a predetermined set temperature. Based on this and the information on the flow rate of the refrigerant to the heat exchanger 11, the required air volume to the heat exchanger 11 is calculated, and the air volume of the blower 12 is controlled based on this.

Further, when the cooling mode operation is performed using the heat exchanger 11 as an evaporator, a signal from the pipe temperature detector 22 of the refrigerant pipe 2g is received to indirectly determine the evaporation temperature of the refrigerant in the heat exchanger 11. And the opening degree of the expansion valve 23 is controlled so that the evaporation temperature becomes constant.

Thus, one outdoor unit 1 and a plurality of indoor units 3 are controlled and operated simultaneously. Here, assuming that each of the indoor units 3 is in the cooling mode operation, the refrigerant flows as shown by arrows in FIG. That is, the refrigerant discharged from the compressor 10 of the outdoor unit 1 is transferred from the refrigerant pipe 2a to the heat exchanger 11 functioning as a condenser through the refrigerant pipes 2b and 2g by opening the solenoid valve 20a.
The refrigerant flows from the refrigerant tank 26 to the refrigerant pipe 2 while being liquefied there and passing through the check valve 25 of the bypass pipe of the refrigerant pipe 2 h and controlled to the total required refrigerant flow rate by the refrigerant flow control valve 24.
Each of the indoor units 3 enters through i, 2p, 2n.

In each of the indoor units 3, first, the refrigerant flow rate required by each of the indoor units 3 is controlled by a refrigerant flow control valve 44 in the middle of the refrigerant pipe 2 n, and the expansion valve 43.
When the liquid refrigerant enters, the pressure of the liquid refrigerant is reduced to a set evaporation temperature, and in this state, the refrigerant flows into a heat exchanger 31 functioning as an evaporator. It flows out to the pipe 2j.

The cool air of each predetermined air volume cooled by each heat exchanger 31 is sent to the air blow duct 4 by a blower 32 under pressure, and while being controlled by each terminal air volume control unit 7, the required air volume in each air conditioning zone 5. Sent and optimal air conditioning (cooling) according to the air conditioning load of each individual air conditioning zone 5.
Will do.

The heat exchanger 31 in each of the indoor units 3.
The refrigerant flowing out of the refrigerant pipe 2j passes through the refrigerant pipes 2m and 2r because the solenoid valve 40b is open. Refrigerant from each indoor unit 3... Enters the accumulator 21 through the refrigerant pipes 2f and 2d of the outdoor unit 1, is sucked by the compressor 10, and returns.

Next, when the whole of the indoor units 3 is in the heating mode operation, the solenoid valves 20b and 40a are opened so that the refrigerant discharged from the compressor 10 is discharged from the outdoor unit 1 as shown by an arrow in FIG. And each indoor unit 3 ...
Flows in the opposite direction to the previous one. Thus, the heat exchanger 11 of the outdoor unit 1 functions as an evaporator, and the heat exchangers 31 of the indoor units 3 function as condensers. With this, the air blown by the blower 32 is heated by the heat exchanger 31 in each indoor unit 3... And the hot air is controlled by the terminal air flow control unit 7 from the blow duct 4 to each of the air conditioning zones 5. , The air-conditioning (heating) is performed in accordance with the air-conditioning load of each air-conditioning zone 5.

Here, as shown in FIG. 6, among the indoor units 3, the indoor unit 3 in the upper part of the drawing is in the cooling mode operation, and the remaining indoor units 3 in the middle and lower parts of the drawing are in the heating mode operation. In other words, if the cooling / heating mode operation is mixed and the total required refrigerant flow rate for the heating operation mode is larger than the total required refrigerant flow rate for the cooling operation mode, the controller 13 of the outdoor unit 1 The larger heating operation mode is selected, the solenoid valve 20b is opened, the heat exchanger 11 functions as an evaporator, and the total required refrigerant flow rate of the larger operation mode is determined. Discharge capacity control is performed, and further, the opening degree of the refrigerant flow control valve 24 is controlled to set the refrigerant flow rate to the heat exchanger 11 of the outdoor unit 1 to a flow rate corresponding to the difference between the two.

As shown by the arrows in FIG. 6, the refrigerant discharged from the compressor 10 of the outdoor unit 1
When the solenoid valve 20a is closed, the refrigerant flows from the refrigerant pipe 2a to the refrigerant pipes 2k of the middle and lower indoor units 3 in the heating mode operation via the refrigerant pipes 2c and 2q. Then, it flows through the solenoid valves 40a of the middle and lower indoor units 3 to the heat exchanger 31 functioning as a condenser, where the blower 3
The refrigerant flows into the refrigerant pipe 2n while exchanging heat with the air blown by the refrigerant pipe 2 and liquefied.

A predetermined amount of warm air heated by the heat exchangers 31 of the middle and lower indoor units 3 is sent to the blow duct 4 by the blower 32 and is controlled by each terminal air flow control unit 7 to control each air conditioner. The required air volume is sent to each zone 5..., And optimal air conditioning (heating) according to the air conditioning load of each air conditioning zone 5 is performed.

The refrigerant is liquefied in the heat exchanger 31 and the refrigerant pipe 2n
Flows into the refrigerant pipe 2p while the flow rate is controlled by the refrigerant flow control valve 44 through the check valve 45 of the bypass pipe.

A part of the liquefied refrigerant enters the refrigerant pipe 2n of the indoor unit 3 in the cooling mode operation at the upper stage, and while being controlled to the required refrigerant flow rate by the refrigerant flow control valve 44, the liquid refrigerant is expanded by the expansion valve 43. The pressure is reduced to the set evaporating temperature, and in this state, the air flows into the heat exchanger 31 functioning as an evaporator, where it exchanges heat with the air blown by the blower 32 and flows out into the refrigerant pipe 2j while evaporating and evaporating.

The heat exchanger 31 of the upper indoor unit 3
Is cooled by the blower 32 and sent to the air duct 4 by the blower 32, and is sent to each of the air conditioning zones 5 by the required air volume while being controlled by the terminal air volume control units 7, so that the individual air conditioning zones 5 are controlled. Optimum air conditioning (cooling) according to the air conditioning load is performed.

The heat exchanger 31 of the upper indoor unit 3
The refrigerant flowing out of the refrigerant pipe 2j passes through the refrigerant pipe 2m because the solenoid valve 40b is open, and further flows through the refrigerant pipe 2j.
The air enters the accumulator 21 via f and 2d, and is sucked by the compressor 10 and returned.

On the other hand, the remainder of the refrigerant liquefied and flowing out to the refrigerant pipe 2p is passed through the refrigerant pipe 2i to the outdoor unit 1.
Into the required refrigerant flow rate by the refrigerant flow rate adjusting valve 24 of the refrigerant pipe 2h.
The liquid refrigerant is decompressed by the expansion valve 23 so as to reach the set evaporation temperature. In this state, the heat exchanger 11 which functions as an evaporator
Flows therethrough and exchanges heat with the air blown by the blower 12, and flows out to the refrigerant pipe 2g while evaporating and evaporating. From there, it passes through the refrigerant pipe 2b via the electromagnetic valve 20a, and is again sent to the indoor unit 3 in the heating mode operation from the refrigerant pipe 2c together with the refrigerant discharged from the compressor 10.

Thus, when the cooling / heating mode operation is mixed, the compressor 10 of the outdoor unit 1 operates in the cooling / heating mode.
It is only necessary to discharge the refrigerant corresponding to the total required refrigerant flow rate of the operation mode of the larger one of the heating modes, and the heat exchanger 11 of the outdoor unit 1 has the required refrigerant flow rate of each of the cooling / heating modes. It suffices to perform the evaporation or condensation operation by the amount of the refrigerant corresponding to the difference.

[0062]

According to the first aspect of the present invention, since the air conditioning zone assigned to each indoor unit can be finely and optimally air-conditioned, the operation of the outdoor unit is less wasteful and efficient, and the cost is reduced. A multi-type direct expansion type air conditioner with excellent economic efficiency can be obtained.

In the second invention, since the configuration is as described above,
In addition to the effects of the first aspect, a multi-type direct expansion type air conditioner can be obtained in which each indoor unit can finely and simultaneously air-condition a plurality of air conditioning zones having different air conditioning loads in an optimal state.

In the third and fourth aspects of the present invention, as described above, in addition to the effects of the first and second aspects of the invention, more accurate control can be performed, and the air-conditioning zones assigned to the respective indoor units are further increased. A multi-type direct expansion type air conditioner that can air condition more optimally can be obtained.

In the fifth invention, since the configuration is as described above,
In addition to the effects of the first to fourth aspects of the present invention, even if the cooling / heating mode operation is mixed in a plurality of indoor units, one outdoor unit can efficiently cope with the operation, and the waste of the operation of the outdoor units is reduced. Thus, a multi-type direct expansion type air conditioner can be obtained which is extremely efficient and economical in which cost can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a schematic overall configuration diagram showing one embodiment of an air conditioner of the present invention.

FIG. 2 is a configuration diagram of an outdoor unit of the embodiment.

FIG. 3 is a configuration diagram of the indoor unit of the embodiment.

FIG. 4 is an operation explanatory view showing the flow of the refrigerant during the cooling mode operation of the outdoor unit and the plurality of indoor units of the embodiment.

FIG. 5 is an operation explanatory view showing a flow of a refrigerant in a heating mode operation of the outdoor unit and a plurality of indoor units of the embodiment.

FIG. 6 is an operation explanatory view showing the flow of the refrigerant during the operation in which the cooling / heating mode of the outdoor unit and the plurality of indoor units of the embodiment is mixed.

[Explanation of symbols]

1 outdoor unit, 2 (2a to 2r) ... refrigerant pipe, 3 ...
Indoor unit, 4 ... air duct, 5 ... air conditioning zone, 7 ...
Terminal air volume control unit, 10 ... compressor, 11,
31: heat exchanger, 12, 32: blower, 13, 33: control device, 16, 36: wind speed detector, 17, 37: suction side temperature detector, 18, 38: blowing side temperature detector,
20a, 20b, 40a, 40b: solenoid valve, 21: accumulator, 22, 42: pipe temperature detector, 23, 43
... expansion valves, 24, 44 ... refrigerant flow control valves, 25, 45 ...
Check valve, 26 ... Refrigerant tank.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-176949 (JP, A) JP-A-1-193563 (JP, A) JP-A-2-57851 (JP, A) JP-A-1- 127842 (JP, A) JP-A-64-67572 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24F 11/02 102

Claims (5)

(57) [Claims] 1. A multi-type direct expansion type air conditioner comprising: an outdoor unit; and a plurality of indoor units connected to the outdoor unit via a refrigerant pipe and capable of blowing air to a predetermined air conditioning zone. In the equipment, each of the indoor units controls the air volume of the blower based on the required air volume corresponding to the air conditioning load of the air conditioning zone assigned to each of the indoor units, and the air is actually sent to the heat exchanger by the air blower.
Air volume passing through the heat exchanger, its inlet temperature and outlet
Detects by side temperature, and calculates the difference between required amount of heat exchange of the heat exchanger from the air volume between the set air temperature of the suction side temperature and the heat exchanger, the necessary refrigerant flow rate of the heat exchanger commensurate thereto Determining the refrigerant flow regulating valve and controlling the blowing
Required cooling based on the difference between the side temperature and the set blowing temperature.
Each of the outdoor units has a controller that corrects the medium flow rate, while the outdoor unit determines the total refrigerant flow rate based on the required refrigerant flow rate information from the control unit of each indoor unit and controls the discharge capacity of the compressor and the refrigerant. An air conditioner comprising a control device for controlling a flow control valve. 2. Each of the indoor units is connected to a plurality of air-conditioning zones via a terminal air volume control unit so as to be able to blow air, and a control device of each of the indoor units controls the air-conditioning of each of the plurality of air-conditioning zones. 2. The air conditioner according to claim 1, wherein a required air volume command corresponding to the load is received from the terminal air volume control unit, and a required air volume of the total is calculated to control the air volume of the blower. 3. The control device of each indoor unit detects the amount of air sent to the heat exchanger and the temperature of the suction side thereof, and determines the difference between the temperature of the suction side and the set outlet temperature of the heat exchanger and the amount of air flow. Calculating the required amount of heat exchanged from the heat exchanger, and detecting means for detecting the temperature on the outlet side of the heat exchanger.From the difference between the actual outlet side temperature and the set outlet temperature, the temperature of the heat exchanger is determined. 2. The air conditioning equipment according to claim 1, wherein the required amount of exchanged heat is corrected, the required refrigerant flow rate of the heat exchanger corresponding to the required amount of heat exchange is determined, and the refrigerant flow control valve is controlled. 4. The control device of each indoor unit detects the amount of air sent to the heat exchanger and the temperature of the suction side thereof, and calculates the difference between the temperature of the suction side and the set outlet temperature of the heat exchanger and the amount of air flow. Calculating the required amount of heat exchanged from the heat exchanger, and detecting means for detecting the temperature on the outlet side of the heat exchanger.From the difference between the actual outlet side temperature and the set outlet temperature, the temperature of the heat exchanger is determined. The air conditioning equipment according to claim 2, wherein the required amount of exchanged heat is corrected, the required refrigerant flow rate of the heat exchanger corresponding thereto is determined, and the refrigerant flow control valve is controlled. 5. The outdoor unit control device receives each cooling / heating mode operation information and each required refrigerant flow rate information from the control device of each indoor unit, and sums up the required refrigerant flow rates for the cooling mode operation. And the total required refrigerant flow rate for the heating mode operation and the total required refrigerant flow rate of the larger operation mode are determined, and the operation mode switching control of the outdoor unit and the discharge of the compressor corresponding to this are determined. 5. The refrigerant flow control valve according to claim 1, wherein a capacity control is performed, and a refrigerant flow rate to the heat exchanger of the outdoor unit is determined to be a flow rate corresponding to a difference between the two and the refrigerant flow control valve is controlled. The air conditioning equipment according to any of the above.