JPH04161750A - Air conditioning system - Google Patents

Abstract

PURPOSE:To enable a positive air conditioning to be carried out in response to a cooling requirement and a heating requirement by a method wherein both cooling and heating operations are performed alternatively under a time-sharing basis when the cooling requirement and the heating requirement overlap to each other, refrigerant is supplied only to an indoor heat exchanger requiring the cooling operation for cooling operation and refrigerant is supplied only to the indoor heat exchanger requiring the heating operation for heating operation. CONSTITUTION:In the event that only a room A of the rooms A, B and C is in a cooling state and a heating requirement is set in the room B, a control circuit 35 controls a changing- over of a four-way valve 31 so as to cause a cooling or a heating operation to be alternatively carried out in a time-sharing basis and at the same time two-way valves 19, 21 for an indoor heat exchanger 7 and two-way valves 23, 25 for an indoor heat exchanger 9 are alternatively opened or closed synchronously with this alternative operation. With such an arrangement, the room A is subsequently cooled, the room B is newly heated and then a time ratio between the cooling and heating becomes 1:1. After this operation, when a heating requirement is newly set at the room C, the number of rooms to be heated becomes twice in respect to the number of rooms to be cooled, so that the time ratio between the cooling operation and the heating operation is set to 1:2 and the alternating operation is continued.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) The present invention relates to an air conditioning system for heating and cooling a plurality of rooms.

(Prior technology) In recent years, with the miniaturization and higher performance of various devices that make up air equipment, multiple indoor heat exchangers are connected in parallel to one outdoor heat exchanger. BACKGROUND ART Multi-room air conditioners that can cool or heat rooms at the same time are becoming popular in general households.

By the way, since a multi-room air conditioner has only one outdoor heat exchanger, the heat of the refrigerant is discharged into the air or absorbed through this outdoor heat exchanger depending on heating or cooling. Since only one of the heat exchange functions can be performed, if contradictory demands for cooling and heating overlap, it is impossible to perform air conditioning that meets one of the demands. However, in the spring and autumn seasons, conflicting cooling and heating requirements from different rooms may overlap due to differences in sunlight and individual differences in temperature sensation, so it is necessary to ensure comfort in each room. Some kind of countermeasure was desperately needed.

(Problems to be Solved by the Invention) As described above, in conventional multi-room air conditioners, it has been impossible to perform air conditioning that meets the conflicting overlapping demands of cooling and heating.

The present invention has been made in view of the above, and an object of the present invention is to provide an air conditioning system that can perform accurate air conditioning that meets the conflicting demands of cooling and heating, even when these demands overlap. It is in.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the present invention provides an air conditioner in which a plurality of indoor heat exchangers are connected in parallel to a refrigerant path. The gist is to perform cooling and heating operations alternately, and to control the supply of refrigerant to the required indoor heat exchangers in response to cooling and heating requests in synchronization with the alternating cooling and heating operations. do.

(Function) In the air conditioning system according to the present invention, when cooling and heating requests overlap, cooling and heating operations are performed alternately in a time-sharing manner, and during cooling operation, the indoor heat that was requested for cooling is Refrigerant is supplied only to the exchanger, and during heating operation, refrigerant is supplied only to the indoor heat exchanger that has received a heating request.

(Example) Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a diagram showing the configuration of an air conditioner according to a first embodiment of the present invention. In the figure, 1 is a compressor, 3 is an outdoor heat exchanger, 5 is an expansion valve, 7, 9°, 11 is an indoor heat exchanger installed in each room, and 13°, 15, 17 is an air conditioning unit for each room. An operation unit for setting demand and target temperature, etc., 19, 21゜23.25, 27.29 are two-way valves for controlling the supply of refrigerant to each indoor heat exchanger 7, 9゜11;
31 is a four-way valve that changes the flow of refrigerant in the refrigerant passage 33 to switch between air conditioning and heating. Further, 35 is a control circuit that controls the operation of the entire air conditioner described above.

In this air conditioner, under the control of the control circuit 35, the four-way valve 31 is controlled to guide the refrigerant gas exiting the compressor 1 to the indoor heat exchangers 7, 9, 11, so that the refrigerant reaches a high temperature. It becomes gas and exits the compressor and enters indoor heat exchangers 7 and 9.
．． 11, heat is discharged to the indoor air to lower the temperature, and after passing through the expansion valve 5, heat is absorbed from the outdoor air while passing through the outdoor heat exchanger 2, thereby performing heating.

In addition, the four-way valve 31 directs the refrigerant gas exiting the compressor 1 to the outdoor 11.
It cools the room by absorbing heat from the indoor air.

Next, the operation of this embodiment will be explained with reference to the time chart of FIG. 2 in the case where requests for cooling and heating overlap.

Room A (corresponding to indoor heat exchanger 7), Room B (corresponding to indoor heat exchanger 9)
room C (corresponds to indoor heat exchanger 11), room A (corresponds to indoor heat exchanger 11)
When only the room is in the cooling state (period t1), when a heating request is received via the operation unit 15 of room B, the control circuit 35:
The four-way valve 31 is switched and controlled to alternately perform heating and cooling operations in a time-sharing manner, and in synchronization with this alternate operation, the two-way valves 19 and 21 for the indoor heat exchanger 7 and the two-way valve for the indoor heat exchanger 9 are switched. 23 and 25 are alternately opened and closed (period t
2). As a result, room A will continue to be cooled, and room B will be newly heated. In this case, in the alternate operation, the number of rooms to be air-conditioned is the same, so the time ratio (A:B) of cooling and heating is 1:1.

After this, when a new request for heating is received in room C, the number of rooms to be heated will be twice as many as the number of rooms to be cooled, so we will continue to operate alternately with the time ratio of cooling and heating being 1:2. (period ti).

Therefore, according to this embodiment, when requests for cooling and heating overlap, the heating and cooling operations are alternately operated at a time ratio corresponding to the number of rooms, so there are no problems like in the past. It is possible to satisfy both requests when there are duplicate requests.

In the above-mentioned embodiment, the time ratio of the alternate operation is changed to perform appropriate air conditioning according to the increase or decrease in the number of air-conditioned rooms, but as shown in Fig. 3, the rotation speed of the compressor may be changed, and in this case, the time ratio (A
:B) may be constant.

FIG. 4 is a time chart showing a second embodiment of the present invention. Its feature is that the time ratio of alternate operation of air conditioning and heating is controlled not only by the number of rooms but also by taking into account the difference between the target temperature and the indoor temperature and the outside temperature.

That is, while cooling and heating are being operated alternately at a 1:1 time ratio based on the cooling request from Room A and the heating request from Room B (period t4), the operation unit 13 of Room A is operated. When the target temperature is lowered, it is necessary to increase the flow rate of refrigerant for cooling, so even if the number of rooms is the same, the time ratio (A:B) is alternately operated with 2 cooling units and 1 heating unit. (period ts). Additionally, if the outside temperature drops after this, the efficiency of the air conditioner increases and the efficiency of the heating decreases, so to adjust this, the time ratio (A:B) is returned to 1:1 and alternate operation is performed. period t6).

Regarding the time ratio, for example, values as shown in FIG. 5 are stored in the control circuit 35 as a data table.
Settings are controlled based on this.

Therefore, according to this embodiment, in addition to the effects of the first embodiment described above, it is possible to achieve more accurate air conditioning for each room.

In addition, in the above-mentioned embodiment, the time ratio of alternate operation (A:
By changing B), appropriate air conditioning is performed according to the increase or decrease in the number of air-conditioned rooms, the difference between the target temperature and the indoor temperature, and changes in the outside temperature.As shown in Figure 6, the compressor The number of rotations may be changed, and in this case, the time ratio (A:B) may be constant.

[Effects of the Invention] As explained above, according to the present invention, when cooling and heating requests overlap, cooling and heating operations are performed alternately in a time-sharing manner, and during cooling operation, an unexpected cooling request is performed. Refrigerant is supplied only to the internal heat exchanger, and during heating operation, refrigerant is supplied only to the internal heat exchanger that has a heating request, so even if contradictory demands for cooling and heating overlap, the requirements for both are met. Accurate air conditioning is possible according to the situation.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of the first embodiment of the present invention, FIGS. 2 and 3 are time charts for explaining the operation of the first embodiment, and FIG. 4 is a diagram showing the configuration of the first embodiment of the present invention. FIG. 5 is a time chart diagram showing the operation of the second embodiment, FIG. 5 is a diagram for explaining the second embodiment, and FIG. 6 is a time chart diagram showing a modification of the second embodiment. 1... Compressor 3... Outdoor heat exchanger 5... Fat expansion valve 31... Four-way valve 33... Refrigerant passage 35... Control circuit

Claims (1)

[Claims] In an air conditioner in which multiple indoor heat exchangers are connected in parallel to the refrigerant path, when cooling and heating requests overlap, cooling and heating operations are performed alternately, and the required operation is performed according to the cooling and heating requests. An air conditioning system characterized by controlling the supply of refrigerant to an indoor heat exchanger in synchronization with the alternating operation of air conditioning and heating.