JPS62178835A - Air conditioner - Google Patents

Abstract

PURPOSE:To carry out stable operation by constituting a device in such a way that variable air amount control or constant air amount control is chosen according to the number of air conditioned rooms. CONSTITUTION:Signals whether each room is air-conditioned or not and the values of set room temp. TO and present room temp. TR at each room are fed into a microcomputer 18 from each room thermostat 7a-7d. Then, when air conditioning is carried out for two rooms or more, opening of dampers 4a-4d of the air-conditioned rooms is controlled based on the difference between TO and TR. Signals of pressure and ventilating air temp. in a duct 3 are fed into the computer 18 from a pressure detector 5 and a temp. detector 6 to change the capacity of a blower 2 with a blower controller 28. Next, the number of air-conditioned rooms is judged and when air conditioning is carried out for two rooms or more, the capacity of a heat source device 1 is changed by a controller 26 for the heat source device. When the number of air-conditioned rooms is judged to be one, the damper of the air-conditioned room in the dampers 4a-4d is fully opened and the capacity of the device 1 is controlled. Thereby, optimum ventilating air amount and temp. are able to be controlled according to the number of air-conditioned rooms.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a duct type air conditioner that employs a variable air volume control method that independently adjusts the room temperature of each room, and particularly relates to its control. .

[Conventional technology]

In air conditioners, using air ducts.

Various types of central air conditioning systems have been developed in which variable air volume control (hereinafter referred to as VAV control) is applied to central air conditioning systems that perform air conditioning (hereinafter referred to as air conditioning) by distributing temperature-controlled air to each room. Here, VAV control is to keep the air temperature constant and adjust the damper opening degree of each room according to the heat load status of each room, thereby varying the air volume and keeping the room temperature constant at the set value. It is something. Buildings that adopt this type of air conditioning control are offices and other buildings.
In this case, most of the rooms are air-conditioned, and the time of day is also constant. In addition, since the indoor environment is determined by law, ventilation must be performed, and even if there is an air conditioning load, there is at least a heat load associated with ventilation, and an air volume is required for ventilation.

There is a method of using a throttle damper and a bypass damper to adjust the air flow rate in VAV control, but conventional techniques that use a throttle damper include Japanese Patent Application Laid-Open No. 57-196029 and Refrigeration and Air Conditioning published by the Japan Refrigeration Association. Figure 2.10(a) of the handbook (new edition, 4th edition, advanced edition) is well known. Figure 5 is a characteristic diagram showing the relationship between the air flow rate and air temperature for the cooling load shown in Figure 2.14 of the Refrigeration and Air Conditioning Handbook. However, when the load falls below a certain value, the amount of air blown is fixed, and only the temperature of the air blown is varied to balance it with the heat load. This type of control ensures the minimum amount of air flow (ventilation amount) even at low loads. However, if there is a large difference in the heat load between rooms, it is not possible to accurately control the room temperature unless a reheating coil or the like is installed in each room. Note that control in which the air blowing temperature is varied while keeping the air blowing amount constant is called constant air volume control (hereinafter referred to as CAV control).

[Problem to be solved by the invention] Conventional building air conditioners were controlled as described above, but when VAV control is applied to residential air conditioning, the usage method is different from building air conditioning. . First, in the case of houses, the number of rooms that require air conditioning varies greatly depending on the time of day, ranging from a minimum of one room to a maximum of all rooms, and the number of rooms is also small. In addition, since ventilation is often not performed, the amount of air blown into each room is also large ((
damper opening (up to 0%). Therefore, the total heat load varies greatly depending on the time of day and other factors. Now, as a heat source device for an air conditioner, it is possible to use a variable type heat pump using an inverter or the like, or a variable capacity gas furnace, but the range in which capacity can be controlled is limited. Furthermore, even if the heat load is small, the capacity cannot be lowered to the minimum value in order to maintain a constant air temperature, and for this reason, when only one room is air-conditioned using VAV control, the heat source equipment often oscillates. There was a problem.

The object of the present invention is to provide an air conditioner that can optimally control the amount of air blown and the temperature of air blown depending on the number of rooms to be air-conditioned.

[Means for solving problems]

An air conditioner according to the present invention includes a variable capacity heat source device, a variable capacity blower, a plurality of dampers inserted in a duct, a pressure detector and a temperature detector provided in the duct, and a room A number of air-conditioned rooms detection means detects the number of air-conditioned rooms based on a detection signal from a thermostat or the like, and a control method selection means selects control between variable air volume and constant air volume based on the output of this air-conditioned room number detection means. It is something.

[Effect]

In this invention, the air-conditioned room number detection means detects the current number of air-conditioned rooms from the operation and stop state of the air conditioning in each room set by a room thermostat, etc., and the control method selection means detects the output of the air-conditioned room number detection means. In the case of a room, the control of the damper, blower, and heat source device is set to constant air volume control, and in the case of multiple rooms, variable air volume control is selected.

〔Example〕

FIG. 1 is an overall configuration diagram showing an embodiment of an air conditioner according to the present invention. As is clear from FIG. 1, this embodiment includes a variable capacity heat source device 1 such as a heat pump that generates cold and hot air, a variable capacity blower 2 connected to this heat source device 1, and a variable capacity blower 2 that distributes the cold and hot air. a duct 3, a plurality of dampers 4a to 4d provided in the duct, a pressure detector 5 to detect the pressure inside the duct 3, a temperature detector 6 to detect the temperature, and a plurality of room thermostats 7a to 7d. The number of rooms currently being air-conditioned is detected by the air-conditioned room number detection means 8 based on the output signals of the room thermostands 7a to 7d, etc., and based on the output of the detection means 8, the damper 4, the blower 2 and It is constituted by a control method selection means 9 that selects either variable air volume control or constant air volume control to control the heat source device 1.

FIG. 2 is a system configuration diagram of an air conditioner used in the embodiment of FIG. 1. In the figure, 10 is an indoor unit that is installed in the ceiling of a building and includes a heat exchanger 11 connected to the heat source device 1 and the blower 2, and 12a to 12d are indoor units 10.
The four ducts of the duct 3 connected to the
The dampers 4a to 4d are installed in the middle. 1
3a to 13d are air outlets installed on the ceiling surface at the ends of branch ducts l-12a to 12d, 14a to 14d are suction ports provided at the bottom of each room's door, and 15 is a ceiling suction installed on the ceiling surface of the hallway. 16 is a return duct that connects this ceiling suction port 15 and the indoor unit 10, and 17 is a control device that controls the entire air conditioner. Although not shown, the room thermostats 7a to 7d installed in each room have an operation switch for selecting whether or not to air condition the room, a room temperature detector for detecting the room temperature, and a room temperature setting for inputting the set room temperature. The machine is equipped. Also, the above duct 3
The pressure detector 5 and temperature detector 6 are installed inside.

FIG. 3 is a circuit diagram showing the electrical connections of the entire system, most of which are housed in the control device 17.

18 is a microcomputer provided in the control device 17, and includes input circuits 19°, CPU 20. memory 21
．． Timer 22. An output circuit 23 is provided. Is 24 the room thermostat mentioned above? a to 7d, pressure detector 5. This is an analog multiplexer to which a temperature detector 6 is connected, and is connected to the input circuit 19 via an A/D converter 25.

26 is a heat source device controller for controlling the capacity of the heat source device 1, and is connected to the output circuit 23 via a photocoupler 27a. A blower controller 28 controls the capacity of the blower 2, and is connected to the output circuit 23 via a photocoupler 27b. A damper controller 29 controls the opening degree of the damper 4, and is connected to the output circuit via a photocoupler 27c. 30 is the heat source device controller 26. This is a power source that supplies power to the blower controller 28 and damper controller 29.

Next, the operation of the above embodiment will be explained with reference to the control flowchart shown in FIG. First, in step 31, a signal indicating whether each room is being air-conditioned is sent from each room thermostat 7a to 7d to the analog multiplexer 24 and the A/
The signal is input to the microcomputer 18 via the D converter 25. At the same time, in step 32, the set temperature T0 of each room is set from each room thermostat 7a to 7d.
and the value of the current room temperature TR are input to the microcomputer 1B. In the next step 33, the number of air-conditioned rooms is determined, and if two or more rooms are being air-conditioned, the process moves to step 34. T in step 34. The opening degree of the dampers 4a to 4d in the room being air-conditioned is controlled based on the difference between and TH. Control signals for the dampers 4a to 4d are transmitted from the microcomputer 18 to the damper control device via the photocoupler 27C to change the opening degrees of the dampers 4a to 4d. In step 35, signals of the pressure inside the duct 3 and the air blowing temperature after controlling the dampers 4a to 4d are inputted to the microcomputer 18 from the pressure detector 5 and the temperature detector 6.

In the next step 36, the blower controller 28 controls the blower 2 so that the pressure inside the duct 3 is maintained at the set pressure.
The capacitance of is changed. In step 37, the number of air-conditioned rooms is judged again, and if two or more rooms are being air-conditioned, the process moves to step 38, and the heat source device controller 26 maintains the air blowing temperature in the duct 3 at the set temperature. The capacity of the heat source device 1 is changed so that the The above control is performed by VA.
Became the master of VilJ. Note that if the number of air-conditioned rooms is determined to be one in steps 33 and 37 above, steps 39 and 40 are performed.
is executed. In step 39, the dampers 4a to 4d of the room being air-conditioned are fully opened, and in step 40, the T input in step 32 is reached. The capacity of the heat source device 1 is controlled based on the difference between and TR. In other words, when the temperature difference is large, the capacity is controlled to be large, and when it is small, the capacity is controlled to be small. In this case, CVA control is performed by controlling the blower 2 so that the set pressure is the same as in the previous VAV control.

Through the above control, the capacity of the heat source device 1 is controlled according to the heat load, and the blowing temperature is varied during air conditioning of one room. As a result, the heat source unit 1 is operated at a capacity that is balanced with the heat load, and in order to maintain the air blowing temperature as in the past, it is operated at a capacity that is greater than the heat load, causing the room temperature to exceed the set value. This prevents the heat source device 1 from frequently turning on and off. Also, when air conditioning one room, dampers 4a to 4
Since d is fully opened, there is less pressure loss in the ventilation system.
The power of the blower 2 is also saved.

In the above embodiment, signals from the room thermostats 7a to 7d are used to detect the number of rooms being air-conditioned, but these may be signals from a controller (not shown).

In addition, in the above embodiment, the number of operating switches set by the user on the room thermostat etc. was used to determine the number of air-conditioned rooms, but the heat load is small, and as a result, the damper is fully open or close to fully closed. Rooms that have become air conditioned may also be treated as non-air conditioned rooms.

Further, in the above embodiment, the set pressure and temperature within the duct 3 are controlled to be constant, but the present invention may be applied to control in which these are varied within a fixed range due to heat load or the like.

Further, in the above embodiment, the pressure detector 5 is provided in the duct 3 to control the pressure at a constant level, but if the pressure can be controlled at a substantially constant level by other means, the pressure detector 5 may not be used.

〔Effect of the invention〕

As described above, according to the present invention, since variable air volume control and constant air volume control are used depending on the number of rooms being air-conditioned, the number of turns on and off of the heat source unit when air-conditioning a single room is reduced, and stable operation is achieved. I can do it.

[Brief explanation of drawings]

Fig. 1 is an overall configuration diagram of an embodiment of an air conditioner according to the present invention, Fig. 2 is a system configuration diagram using the air conditioner shown in Fig. 1, and Fig. 3 shows the electrical system of Fig. 2. Circuit diagram, 4th
The figure is a flowchart showing the control operation of FIGS. 1 to 3,
FIG. 5 is a characteristic diagram showing the relationship between cooling load and air volume of a conventional air conditioner. 1 is a heat source device, 2 is a blower, 3 is a duct, 4a to 4d are dampers, 5 is a pressure detector, 6 is a temperature detector, 7a to 7d are room thermostats, 8 is a means for detecting the number of air-conditioned rooms, and 9 is a control system means of selection. In addition, in the figures, the same reference numerals indicate the same or corresponding parts. Figure 5 → Cooling load procedure amendment (voluntary) 1. Indication of the case: Japanese Patent Application No. 61-21554 2, Title of the invention: Air conditioner 3, Representative of the person making the amendment: Moriya Shiki 5, Subject of amendment (1) Detailed description of the invention in the specification (2) Drawing 6, Contents of amendment (1) On page 4, lines 11 and 12 of the specification cylinder, the words "variable type using an inverter etc." and "candy" are amended to read "variable capacity type using an inverter etc." (2) On page 4, line 18, the phrase ``oscillation'' is corrected to ``U starts and stops.'' (3) The phrase "based on" on page 5, line 7 of the same document is amended to read "based on." (4) On page 7, line 13, replace ``1 room temperature setting machine'' with ``
"Room temperature setting device". (5) On page 10, lines 8 and 9, “Fully opened...
"To" is fully opened, and dampers 4a to 4dζ in other rooms are fully closed. In step 40, T of the room being air-conditioned was input in step 32 above. ] and correct it. (6) On page 10, line 13 of the same page, amend the phrase ``control and the previous'' to ``1 control is the first''. (7) On the 10th page, line 14, the text "rCVA control" is corrected to "rcAV control". (8) On page 11, line 3, the phrase ``Also, when one room is air-conditioned, the damper'' has been corrected to ``Also, when one room is air-conditioned, the damper of the room being air-conditioned''. (91, page 11, line 13, ``Full open j'' is corrected to ``fully closed''. 001 Drawings 1 and 4 are corrected as shown in the attached sheet. 7. Attached documents

Claims (1)

[Claims] (1) A variable-capacity heat source machine that generates hot air or cold/hot air, and a variable-capacity blower connected to this heat source machine,
A duct that distributes cold and hot air supplied from this blower,
A damper for adjusting the air volume placed in each branch of the duct, a pressure detector for detecting the blowing pressure in the duct, and a temperature detector for detecting the blowing temperature in the duct are placed in each room. In an air conditioner equipped with a room thermostat, the number of air conditioned rooms detecting means detects the operating and stopping state of the air conditioning in each room set by the room thermostat, etc., and the number of air conditioned rooms detected by the number detecting means The air conditioner is characterized in that it is equipped with a control method selection means that selects constant air volume control for controlling a damper, blower, and heat source device when the number of rooms is one, and selects variable air volume control when there are multiple rooms.