JP3144855B2 - Air conditioner - 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 controlling an ability to maintain a constant blowing temperature.

[0002]

2. Description of the Related Art As a conventional air conditioner for performing constant blow-off temperature control, there is one disclosed in Japanese Patent Application Laid-Open No. 2-122138.

[0003] Hereinafter, an air conditioner that performs the above-described conventional blow-out temperature constant control will be described with reference to the drawings. FIG.
Is a schematic configuration diagram showing a conventional air conditioner, 1 is a duct type indoor unit main body, and detects the temperature of air blown out by the indoor heat exchanger 2, the indoor blower 3, and the indoor blower 3 therein. And a blowout temperature detector 4 for detecting the temperature. Reference numeral 5 denotes an outdoor unit main body, in which a variable capacity compressor 6, an outdoor heat exchanger 7,
An outdoor blower 8 and a compressor controller 9 for controlling the performance of the compressor 6 are provided.

A duct 11 connects the indoor unit main body 1 to the room to be air-conditioned 10, and guides warm air or cold air to the room to be air-conditioned 10. A variable air volume unit 12 is provided in the middle of the duct 11 to control the room temperature of the room to be air-conditioned 10 by changing the air volume. Reference numeral 13 denotes a return duct,
The air is guided from 0 to the indoor unit main body 1. 14 is an intake duct,
An exhaust duct 15 includes an air supply duct 14 and an exhaust duct 15.
In any case, a fan 1 as a supply / exhaust device in the middle of the duct
4a, 15a, exhausts a part of the air in the return duct 13 and supplies outside air to the air-conditioned room 10
Is ventilating.

Reference numeral 16 denotes an air volume control device for the variable air volume unit 12, which is detected by a room temperature detector 19 and a set room temperature T0 set by a room temperature setter 18 provided in a room temperature controller 17 in the room to be air-conditioned. The damper (not shown) and the motor (not shown) in the variable air volume unit 12 are controlled by the difference from the room temperature T1 to control the air volume passing through the duct 11.

[0006] The operation of the air conditioner configured as described above, which performs the blow-off temperature constant control, during cooling will be described below with reference to FIG.

The difference (step a) between the set room temperature T0 set by the room temperature setting device 18 in the room temperature controller 17 and the room temperature T1 detected by the room temperature detector 19 is T1-T0> 0 at the time of cooling / heating.
In this case, the air volume controller 16 controls the variable unit 12 so that the air volume in the duct 11 increases (step b). Conversely, when T1-T0 <0, control is performed to reduce the air volume in the duct 11 (step c).

At this time, in order to secure the ventilation air volume of the room to be air-conditioned 10, the variable air volume unit 12 does not reduce the air volume passing through the duct 11 at least to a predetermined air volume. Thus, the amount of air passing through the duct 11 changes,
The compressor controller 9 varies the capacity of the compressor 6 so that the blowout temperature detected by the blowout temperature detector 4 in the indoor unit main body 1 is always constant (step d).

As described above, air is always blown from the indoor unit main body 1 at a constant blowing temperature, and the air volume supplied to the air-conditioned room 10 is changed by the variable air volume unit 12 to air-condition the air-conditioned room 10. It is.

[0010]

However, in the above-mentioned conventional structure, even if the air-conditioning load of the room to be air-conditioned decreases, the supply air volume cannot be reduced below a certain air volume in order to secure the ventilation air volume. However, there is a disadvantage that the room to be air-conditioned is too cold, and when heated, it is too warm, that is, the performance of the air conditioner does not decrease.

According to the present invention, when the air-conditioning load of the room to be air-conditioned is reduced, the air-conditioned room is not cooled too much during cooling or overheated during heating to secure a ventilation air volume and maintain a comfortable indoor environment. Aim.

[0012]

In order to achieve the above object, in the air conditioner of the present invention, a blower temperature detector for detecting a temperature of blown air from an indoor unit main body, and a compressor for controlling operation of the compressor. It has a control device and a CPU for controlling the compressor controller.

The CPU causes the compressor controller to control the capacity of the compressor so that the blown air temperature detected by the blowout temperature detector becomes a preset temperature. Drive at the minimum capacity and
If the blown air temperature is lower than the set temperature by a certain temperature during cooling or by a certain temperature during heating, the compressor is controlled so as to stop the operation thereof, and the operation of the compressor is stopped a predetermined number of times within a predetermined time. In this case, control is performed such that the set temperature of the blow-out air temperature is increased by a predetermined value during the cooling operation and decreased by a predetermined value during the heating operation.

[0014]

In the air conditioner of the present invention, when the air-conditioning load of the room to be air-conditioned is reduced, the amount of air passing through the duct is reduced by the variable air volume unit, and the temperature of the air discharged from the air conditioner decreases during cooling and increases during heating. Change. At this time, the CPU controls the capacity of the compressor so as to keep the blown air temperature constant. Further, when the compressor is operated at the minimum capacity and the blow-out air temperature is lower than the set temperature by a certain temperature during cooling or by a certain temperature during heating, control is performed to stop the operation of the compressor.

When the operation of the compressor is stopped a predetermined number of times within a predetermined time, the CPU increases the set temperature of the air blown from the indoor unit by a predetermined value during the cooling operation (decreases the predetermined value during the heating operation). The compressor controller controls the capacity of the compressor (reduces the capacity) so that the temperature of the air blown out from the indoor unit body becomes the newly set temperature.

As a result, the temperature of the air blown from the indoor unit increases by a predetermined value during the cooling operation (decreases by the predetermined value during the heating operation), and even if the air-conditioning load of the room to be air-conditioned is the same, the air volume passing through the duct is increased by the variable air volume unit. Further, since the variable air volume unit can reduce the air volume to the minimum air volume (ventilation air volume), the capacity of the compressor can be further reduced.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the air conditioner according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, FIG. 2 is a block diagram of the air conditioner of the embodiment, and FIG. 3 is a flowchart showing the operation of the air conditioner of the embodiment.

In FIG. 1, a duct type indoor unit main body 1 is shown.
Is provided with an indoor heat exchanger 2, an indoor blower 3, and an outlet temperature detector 4 inside. The outdoor unit main body 5 includes a variable capacity compressor 6, an outdoor heat exchanger 7, an outdoor blower 8, and a compressor controller 20 inside.

In FIG. 2, reference numeral 21 denotes a CPU for controlling the air conditioner of this embodiment, which compares a set room temperature T0 internally set by a room temperature setter 18 with a room temperature T1 detected by a room temperature detector 19. The outlet temperature t1 detected by the outlet temperature detector 4 is compared with the set outlet temperature t0 set by the outlet temperature setter 23. Outlet temperature comparator 24
, An operation mode detector 25 and a counter 26 for counting the number of times X the compressor 6 is stopped.

The CPU 21 varies the air volume of the variable air volume unit 12 via the air volume controller 16 according to the comparison result of the room temperature comparator 22 and the operation mode detected by the operation mode detector 25. The capacity of the compressor 6 is changed via the compressor controller 20 according to the comparison result of the blow-out temperature comparator 24 and the operation mode detected by the operation mode detector 25, and the blow-out temperature is set based on the number of times the compressor is stopped by the counter 26. The set temperature of the vessel 23 is changed.

Next, a specific example of this operation will be described with reference to the flowchart of FIG. 3 showing the operation during the cooling operation.

When the difference between the set room temperature T0 set by the room temperature setting unit 18 in the room temperature controller 17 and the room temperature T1 detected by the room temperature detector 19 is T1-T0> 0, the air volume control unit 16 Controls the variable air volume unit 12 so that the air volume in the duct 11 increases (step 1). Conversely, T1
If -T0 <0, control is performed to reduce the air volume in the duct 11 (step 1).

At this time, in order to secure the ventilation air volume of the room to be air-conditioned 10, the variable air volume unit 12 does not reduce the air volume passing through the duct 11 at least below a preset air volume. Thus, the amount of air passing through the duct 11 changes,
The compressor controller 20 varies the capacity of the compressor 6 so that the blowout temperature t1 detected by the blowout temperature detector 4 in the indoor unit main body 1 always becomes the set temperature t0 of the blowout temperature setter 23.
(Step 2).

Further, the compressor controller 20 determines that the compressor 6 operates at the minimum capacity and the blow-out temperature t1 is equal to the set temperature t0.
Is lower than the constant temperature A during cooling (t1−t0 ≦ −
A) When the constant temperature B during heating rises (t1-t0 ≧ B), the operation of the compressor 6 is controlled to be stopped (step 3), and the number of stop times X of the compressor 6 counted by the counter 26 is X. Is generated a predetermined number of times within a predetermined time, the set temperature t0 of the blow-out temperature setter 23 is increased by a predetermined value during cooling and reduced by a predetermined value during heating (step 4).

The CPU 21 increases the set temperature t0 of the air blown from the indoor unit body 1 by a predetermined value during the cooling operation (decreases the predetermined value during the heating operation), and sets the temperature t1 of the air blown from the indoor unit body 1 to the newly set temperature. The compressor controller 20 controls the performance of the compressor 6 (reduces the performance) so as to reach t0.

More specifically, when the compressor controller stops the operation of the compressor a predetermined number of times X within a predetermined time, the constant blow temperature t0 is changed to 18 ° C. At this time, the maximum supply air volume to the room to be conditioned 10 is 50 m ³ / min,
Assuming that the minimum supply air volume (air volume required for ventilation) is 20 m ³ / min, the capacity can be reduced only to about 40% if the constant blowing temperature t0 remains at 15 ° C. When the cooling load of the room 10 becomes 40% or less, the room is overcooled.

As in the present embodiment, when the compressor control unit causes the compressor to stop for a predetermined number of times within a predetermined time, the constant outlet temperature t0 is changed to 18 ° C., and the suction temperature of the indoor unit 1 is reduced. Assuming that the temperature is 26 ° C., 20 (26-1)
8) The control from 50/26 (15) = 0.29 to about 29% can be performed while securing the minimum air volume of 20 m ³ / min.

In the case of heating, as in the case of cooling,
The heating capacity control range can be expanded while ensuring the minimum air volume.

As described above, when the operation of the compressor is stopped a predetermined number of times within the predetermined time by the compressor control device, the set temperature t0 of the blowing temperature is increased by a predetermined value during cooling, increased by a predetermined value, and decreased by a predetermined value during heating. As a result, the capacity control range can be expanded while securing the minimum ventilation air volume, and the room to be air-conditioned 1
When the air-conditioning load of 0 is reduced, it is possible to prevent the room from being too cold or too warm.

[0030]

As described above, according to the air conditioner of the present invention, when the operation of the compressor is stopped a predetermined number of times within the predetermined time by the compressor control device, the set temperature of the blown air is set to the predetermined temperature during cooling. Since the control to raise the price and lower the predetermined value during heating is performed,
Even when the air-conditioning load of the room to be air-conditioned is low load, sufficient capacity control can be performed while securing the ventilation air volume, and it is possible to prevent excessive cooling of the air-conditioned room during cooling and excessive heating during heating, There is an effect that a comfortable indoor environment can be maintained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of an air conditioner according to the present invention.

FIG. 2 is a block diagram of the air conditioner of the embodiment.

FIG. 3 is a flowchart showing an operation of the air conditioner of the embodiment during a cooling operation.

FIG. 4 is a schematic configuration diagram of a conventional air conditioner.

FIG. 5 is a flowchart showing an operation of the conventional air conditioner during a cooling operation.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 indoor unit main body 2 indoor heat exchanger 3 indoor blower 4 outlet temperature detector 5 outdoor unit main body 6 compressor 7 outdoor heat exchanger 8 outdoor blower 10 air-conditioned room 11 duct 12 variable air volume unit 16 air volume control device 20 Compressor controller 21 CPU

Claims (1)

(57) [Claims] 1. A duct-type indoor unit body provided in a duct communicating with a room to be air-conditioned and having an indoor-side heat exchanger and an indoor-side blower therein, and a variable-capacity compressor, an outdoor-side heat exchanger therein. An outdoor unit main body having an outdoor blower, a variable air volume unit provided in a duct downstream of the indoor unit main body to change an air flow rate through the duct, an operation mode of the air conditioner, and setting of a room temperature of the room to be air-conditioned. An air volume control device that controls the variable air volume unit so that the room temperature of the room to be air-conditioned matches the set room temperature in accordance with the room temperature; an air temperature detector that detects the temperature of air blown from the indoor unit main body; A compressor control device for controlling the operation of the compressor, and a CPU for controlling the compressor controller, wherein the CPU adjusts the blow-out air temperature detected by the blow-out temperature detector to a preset set temperature. The compressor controller to control the capacity of the compressor so that the compressor operates at the minimum capacity, and the blow-out air temperature is lower than the set temperature by a certain temperature during cooling or a certain temperature during heating. When the temperature rises, the compressor is controlled so as to stop the operation, and when the operation of the compressor is stopped a predetermined number of times within a predetermined time, the set temperature of the blown air temperature is increased by a predetermined value during the cooling operation,
An air conditioner characterized by lowering a predetermined value during heating operation.