JPH04217734A - Duct type air conditioner - Google Patents

Abstract

PURPOSE:To provide a duct type air conditioner capable of getting a comfortable feeling by a method wherein an operation of either a blower or a volume controlling type compressor is controlled in response to a detected state of an operating duct. CONSTITUTION:During a dehumidifying operation, refrigerant compressed by a volume controlling type compressor 6 is sent to an outdoor heat exchanger 7 through a four-way valve 9, radiated and condensed, thereafter the refrigerant is sent to the second indoor heat exchanger 4b through a volume variable type expansion mechanism 8. The refrigerant is reduced in its pressure by an indoor volume variable type expansion mechanism 10 to make refrigerant of low pressure, and the refrigerant evaporates at the first indoor heat exchanger 4a and absorbs heat. Air is cooled and dehumidified by the first indoor heat exchanger 4a disposed at the primary air passage. The air is heated by the second indoor heat exchanger 4b, resulting in that an operation for performing only a dehumidifying operation while keeping its temperature in respect to the air at the inlet port of the indoor device 2 can be realized. An operating frequency of the compressor is decisively controlled in response to the number of detected operation ducts by a frequency control means of the compressor.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention relates to a duct type air conditioner that employs a variable air volume control system that can independently adjust the room temperature in each room. This relates to a duct type air conditioner.

0002

2. Description of the Related Art Some conventional variable air volume control type air conditioners use a blower to distribute and supply cold or warm air to each room through a duct. However, conventional air conditioners are only capable of cooling or heating operations, and are rarely used during the mid-temperature period, which occupies a large portion of the year. As a specific example representative of these conventional examples, Japanese Patent Application Laid-Open No. 64-2305
Selecting the technique described in Publication No. 3, the operation of the conventional example will be explained. FIG. 5 is a configuration diagram showing a conventional duct type air conditioner described in the above-mentioned Japanese Patent Application Laid-Open No. 64-23053.

[0003] In the figure, numeral 1 indicates a room to be air-conditioned that is subject to air conditioning, and this figure shows a case of three rooms. 2 is an indoor unit that is installed in the ceiling of the air-conditioned room 1 and functions as a source of cold or hot air; 3 is an air filter that purifies the air by removing dust from the air; and 4 is an air filter that cools the air. or an indoor heat exchanger for heating, 5 a blower for blowing cold or hot air, 6 a capacity control compressor, 7 an outdoor heat exchanger,
8 is a variable capacity expansion mechanism, and 9 is a four-way valve.

Next, the operation will be explained using FIG. 6. FIG. 6 is a Molière diagram showing a refrigeration cyclone. During cooling operation, the refrigerant compressed by the capacity-controlled compressor 6 is sent to the outdoor heat exchanger 7 by the four-way valve 9, where it radiates heat and condenses, and then is depressurized by the variable-capacity expansion mechanism 8 and becomes a low-pressure refrigerant. It is circulated to the indoor heat exchanger 4 as a heat exchanger. The indoor heat exchanger 4 evaporates and absorbs heat, and the air being circulated by the blower 5 is cooled. During heating operation, the refrigerant compressed by the capacity-controlled compressor 6 is sent to the indoor heat exchanger 4 by the four-way valve 9, where it radiates heat and condenses, and then is reduced in pressure by the variable-capacity expansion mechanism 8 to a low-pressure state. It circulates as a refrigerant to the outdoor heat exchanger 7, where it evaporates and absorbs heat. The refrigerant condenses and radiates heat in the indoor heat exchanger 4 to heat the air being circulated by the blower 5.

[0005]

[Problem to be solved by the invention] Since the conventional duct type air conditioner is configured as described above, the indoor heat exchanger can only function as either a condenser or an evaporator due to the characteristics of the refrigeration cycle. The system is often unable to meet user requests, such as being unable to operate only for cooling or heating, and not being able to operate when only dehumidification is desired, such as during intermediate temperature periods or during the rainy season. there were. Furthermore, although air conditioners capable of dehumidifying operation have existed for some time, they have not been applied to large air conditioners such as those using ducts because the dehumidifying effect is small.

[0006] This invention was made to solve the above-mentioned problems, and a system using ducts can perform cooling and heating operation as well as dehumidifying operation, and even during dehumidifying operation, the dehumidifying effect works sufficiently and the interior The purpose of the present invention is to provide a duct type air conditioner that provides comfort by controlling operation according to the operating duct condition.

[0007]

[Means for Solving the Problems] A duct type air conditioner according to the present invention divides an indoor heat exchanger into two parts, a first indoor heat exchanger and a second indoor heat exchanger, and An indoor variable capacity expansion mechanism is installed between the refrigeration cycle of the indoor heat exchanger, and it has a duct condition detection means to detect the condition of the duct in operation, and also automatically adjusts the operating capacity during dehumidification. The system also has a control means for controlling the operation of the blower or the capacity-controlled compressor in accordance with the detected operating duct condition.

[0008]

[Function] In the duct type air conditioner of the present invention, the temperature of the transported air is reduced by cooling and dehumidifying the transported air by the first indoor heat exchanger and heating (reheating) it by the second indoor heat exchanger. Perform dehumidification operation while maintaining the humidity. Further, the control means automatically increases the operating capacity in the dehumidification mode, and controls the operating capacity based on the number of operations and the open/closed state of the duct detected by the duct state detection means. This allows the dehumidification effect operated by the two-divided indoor heat exchanger to function sufficiently.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, numeral 1 indicates an air-conditioned room to be air-conditioned, and this figure shows a case of three rooms. 2 is an indoor unit that is installed in the ceiling of the air-conditioned room 1 and functions as a source of cold or hot air; 3 is an air filter that purifies the air by removing dust from the air; and 4a is an air filter that cools the air. or a first indoor heat exchanger that heats, 4b a second indoor heat exchanger that cools or heats air, 5 a blower that blows cold or warm air, 6 a capacity control compressor, and 7 an outdoor heat exchanger. ,
8 is a variable capacity expansion mechanism, 9 is a four-way valve, 10 is an indoor variable capacity expansion mechanism, 11 is an operation mode determining means, 12 is an operating duct number detection means which is an example of a duct state detection means, and 13 is a control means. 14 is a duct, 15 is a branch duct, and 16 is a damper. The blower 5, the duct 14, and the branch duct 15 constitute a concentrated ventilation means for blowing air into each of the plurality of air-conditioned rooms 1, and each branch duct 15 is equipped with a damper 16, which is attached to the damper 16. It constitutes an air blow adjustment means that adjusts the amount of air blow by opening and closing the damper 16.

Next, the operation will be explained. During cooling operation, the refrigerant compressed by the capacity-controlled compressor 6 is sent to the outdoor heat exchanger 7 by the four-way valve 9, where it radiates heat and condenses, and then is depressurized by the variable-capacity expansion mechanism 8 and becomes a low-pressure refrigerant. It circulates through the second indoor heat exchanger 4b, the indoor variable capacity expansion mechanism 10, and the first indoor heat exchanger 4a. Here, the refrigerant evaporates and absorbs heat in the first indoor heat exchanger 4a and the second indoor heat exchanger 4b to cool the air being circulated by the blower 5. At this time, the indoor capacity variable expansion mechanism 10 is fully opened.

During heating operation, the refrigerant compressed by the capacity-controlled compressor 6 is passed through the four-way valve 9 to the first indoor heat exchanger 4.
a. It is sent to the indoor variable capacity expansion mechanism 10 and the second indoor heat exchanger 4b, where it radiates heat and condenses, and then is depressurized by the variable capacity expansion mechanism 8 and circulated as a low-pressure refrigerant to the outdoor heat exchanger 7. Endotherms by evaporation. Here, the refrigerant is transferred to the first indoor heat exchanger 4
a and the second indoor heat exchanger 4b condense and radiate heat to heat the air being circulated by the blower 5. At this time, the opening degree of the indoor variable capacity expansion mechanism 10 is fully open.

Next, the dehumidifying operation will be explained using FIGS. 2 and 3. During dehumidification operation, the refrigerant compressed by the capacity-controlled compressor 6 is transferred to the outdoor heat exchanger 7 by the four-way valve 9.
After the heat is radiated and condensed, the variable capacity expansion mechanism 8
The heat is then sent to the second indoor heat exchanger 4b. However, at this time, the variable capacity expansion mechanism 8 is fully opened.
The refrigerant is not depressurized, and the refrigerant radiates heat and condenses in the second indoor heat exchanger 4b as well as in the outdoor heat exchanger 7. Subsequently, the refrigerant is depressurized by the indoor variable capacity expansion mechanism 10 and evaporates and absorbs heat as a low-pressure refrigerant in the first indoor heat exchanger 4a. The air conveyed by the blower 5 on the indoor side is cooled and dehumidified by the first indoor heat exchanger 4a disposed on the primary side of the air path, and is further disposed downstream of the first indoor heat exchanger 4a in the air path. It is heated by the provided second indoor heat exchanger 4b, and as a result, it is possible to realize an operation in which the air on the inlet side of the indoor unit 2 is only dehumidified while maintaining its temperature.

Further, when the dehumidifying operation is selected by the operation mode determining means 11, the compressor operating frequency is determined by the compressor operating frequency control means 13 according to the relationship shown in FIG. The operating frequency of the compressor is determined and controlled according to the number of operating ducts.

Further, the compressor frequency control means 13 automatically increases the operating frequency when the dehumidifying operation is selected by the operation mode determining means 11. For example, if the air conditioner is operated at a frequency fx during cooling/heating operation, and when dehumidifying operation is to be performed next, the air conditioner is operated at a frequency fy greater than or equal to fx (fx<fy). By doing so, the capacity of each of the indoor heat exchangers 4a and 4b, which are divided into two and perform a dehumidifying function, is increased, and even a large system equipped with a duct can sufficiently function as a dehumidifying function.

In the above embodiment, the operating duct number detection means 12 is used as an example of the duct state detection means, but it is possible to detect not only the number of ducts but also the open/closed state of the ducts and the position of the ducts in operation. It may also be something that detects. Alternatively, a combination of these may be detected.

Further, in the above embodiment, the compressor frequency control means 13 is shown as an example of the control means, but it is possible to change not only the frequency of the compressor but also an increase or decrease in the number of compressors. However, it may also be an increase or decrease in the blowing capacity of the blower.

[0017] Furthermore, as explained in the conventional example,
No. 3053 or others, JP-A-55-1213
No. 52, JP-A-62-22948, JP-A-63-30
Each publication of No. 2239 discloses technology related to a duct type air conditioner or an air conditioner equipped with a dehumidifying function, but in particular, no technical disclosure regarding a duct type air conditioner equipped with a dehumidifying function is made. First, the present invention is different from the techniques disclosed in the above-mentioned publications in that the present invention focuses on how to sufficiently exhibit the dehumidifying function in a duct type system.

[0018]

As described above, according to the present invention, the indoor heat exchanger of a normal refrigeration cycle is divided into two parts, a first indoor heat exchanger and a second indoor heat exchanger, and Since a variable capacity expansion mechanism is installed between the refrigeration cycle of the indoor heat exchanger, it is possible to realize not only cooling/heating operation but also dehumidification operation with an indoor unit of the same external shape as a conventional one, making it possible to perform not only cooling and heating operation but also dehumidification operation in summer and winter. The system can be operated even during the mid-temperature period or the rainy season, which has the effect of improving user comfort and increasing the utilization of the system. Furthermore, since the operation of the blower or capacity-controlled compressor is controlled to an optimum value according to the selection of the dehumidification mode or the duct condition, comfort can be further improved.

[Brief explanation of the drawing]

FIG. 1 is an overall system configuration diagram showing one embodiment of the present invention and a block diagram showing control.

FIG. 2 is a Moliere diagram showing a refrigeration cycle according to an embodiment of the present invention.

FIG. 3 is an psychrometric diagram showing the state of the air according to the present invention.

FIG. 4 is a graph diagram showing control details of the present invention.

FIG. 5 is an overall system configuration diagram showing a conventional example.

FIG. 6 is a Moliere diagram showing a conventional refrigeration cycle.

[Explanation of symbols]

1 Air-conditioned room 2 Indoor unit 4a First indoor heat exchanger 4b Second indoor heat exchanger 5　Blower 6 Capacity control type compressor 7 Outdoor heat exchanger 8 Variable capacity expansion mechanism 9 Four-way valve 10　Indoor side variable capacity expansion mechanism 11 Operation mode determining means 12. Means for detecting the number of operating ducts 13 Compressor operating frequency control means 14 Duct 15 Branch duct 16 Damper

Claims (1)

[Claims] 1. A concentrated air blowing means for distributing and blowing air heat exchanged in a heat exchanger to each of a plurality of air-conditioned rooms via a duct and a branch duct, The system is equipped with a ventilation adjustment means that adjusts the amount of cold air or hot air sent to the air-conditioned room by opening and closing a damper, and is equipped with a capacity control compressor, an outdoor heat exchanger, a variable capacity expansion mechanism, and an indoor heat exchanger. In an air conditioner having a refrigeration cycle, the air conditioner has a first indoor heat exchanger and a second indoor heat exchanger, and an indoor capacity variable type air conditioner is provided between the two indoor heat exchangers. an operation mode determining means disposed with an expansion mechanism and determining an operation mode of the air conditioner; and when the operation mode determining means selects a dehumidifying operation, the operating capacity of the blower or the capacity control compressor is determined. It has a duct state detection means for detecting the state of the branch duct being operated, and a control means for controlling the operation of the blower or the capacity control type compressor based on the detected duct state. A duct type air conditioner characterized by: