JPS5854333B2 - Control device for heat pump type air conditioner - Google Patents

Description

Detailed Description of the Invention The present invention provides a control device for an air conditioner that performs heating operation by exchanging heat between an indoor heat exchanger to which a heating medium is supplied from a compressor and air in a conditioned room using a blower. It is related to.

As shown in Fig. 1, a general heat pump type air conditioner has a refrigerant circuit 6 in which a compressor 1, 9F2 on all sides, an outdoor heat exchanger 3, a pressure reducing device 4, and an indoor heat exchanger 5 are connected via piping.
By switching the four-way valve 2, the refrigerant flows in the direction of the solid arrow during cooling, and the refrigerant flows in the direction of the broken arrow during heating, forming a cooling cycle and a heating cycle, respectively.

Further, 7 is an outdoor heat exchanger 3 that acts as a condenser during cooling and an evaporator during heating, and an outdoor blower that promotes heat exchange with the outside air. 3 is a chamber that acts as an evaporator during cooling and a condenser during heating. This is an indoor blower that promotes heat exchange between the inner heat exchanger 5 and the air in the conditioned room.

In the above-mentioned air conditioner, when performing heating operation with the refrigerant circuit 6 in the heating cycle, the indoor heat exchanger 5 is not sufficiently warmed at the beginning of operation, so the indoor blower 8 blows cold air into the room. This will cause discomfort to residents.

Conventionally, the temperature of the indoor heat exchanger 5 is detected, and when the heat exchanger temperature reaches the set temperature, the operation of the indoor fan 8 is stopped or slowed down, and only the compressor 1 and the outdoor fan 7 are operated. was.

However, the temperature of the air blown out from the blower 8, which residents perceive as cold air, differs depending on the room temperature at the time, and when the room temperature is low, the person feels warm even if the air temperature is relatively low compared to when the room temperature is high.

Furthermore, when the room temperature is low, the outside temperature is often low as well, and it may take a long time for the internal heat exchanger 5 to reach the set temperature, which may even make the occupants feel cold.

Furthermore, if the operation is started when the room temperature is close to the comfortable temperature, even if the blower 8 is operated at high speed, the feeling of cold air will be small, and the operation time of the compressor 1 will be shortened, resulting in efficient heating operation. It is something.

The present invention has been made in view of the above-mentioned facts, and is designed to perform heating operation by exchanging heat between an indoor heat exchanger to which a heating medium is supplied from a compressor and air in a conditioned room using a blower. When the temperature of the air-conditioned room is lower than a predetermined temperature, the blower is stopped or operated at a low speed for an appropriate period of time after the start of operation of the compressor, and the air blower is prevented from cold air according to the room temperature, thereby making the room comfortable. An object of the present invention is to provide a control device for an air conditioner that allows heating operation to be performed.

Hereinafter, one embodiment of the device of the present invention will be explained based on the drawings by applying it to the heat pump type air conditioner shown in FIG.
In the figure, reference numeral 9 indicates the temperature of the conditioned room TR and the temperature of the indoor heat exchanger T based on signals from sensors 10 and 11 installed in the conditioned room and the indoor heat exchanger 5, respectively.

This is a temperature detection circuit that detects The conditioned room temperature TR output from the temperature detection circuit 9 is converted into a binary signal and inputted to the room temperature control circuit 12, the cold air prevention detection circuit 13, and the cold air prevention canceling circuit 14.

Also, the indoor heat exchanger temperature T. is converted into a binary signal and supplied to the cold air prevention detection circuit 13 and the cold air prevention cancellation circuit 14.

The room temperature control circuit 12 is supplied with an arbitrary set temperature T8 within a settable temperature range (Tso""rsp, where Tso<T8P) is converted into a binary signal and inputted in advance by the temperature controller 15. and the air-conditioned room temperature TR are compared and calculated to generate a switching signal for the four-way valve 2, a start/stop signal for the compressor 1, and a blower 7, 8.
A 0 start/stop signal and an air volume switching signal are sent to the output control circuit 16.

The cold air prevention detection circuit 13 stores the minimum set temperature Tso and the predetermined temperature To of the temperature regulator 15 as binary signals, and performs the following two comparisons and calculations at the start of heating operation.

TR<TSO or TS...song...(1) To<T
R+To −”・=’ (2) When both equations hold, the output control circuit 16 receives the cold air consisting of the operating signal of the compressor 1 and the stop signal of the indoor blower 8, giving priority to the signal from the room temperature control circuit 12. Issue a prevention order.

The reason for this priority is that the signal from the room temperature control circuit 12 normally has a sequential activation function for operating the indoor blower 80 and then the compressor 1.

The cold air prevention release circuit 14 is at a predetermined temperature T.

is stored as a binary signal and starts operating simultaneously with the output of the cold air prevention detection circuit 13 to perform the next comparison calculation.

T > T + T ・・・・・・・・・(3)R
O When the equation (3) is established, a cold air prevention termination command for canceling the stop signal of the indoor blower 8 is supplied to the output control circuit 16.

Furthermore, the signal from the output control circuit 16 is transmitted to the four-way valve 2 and the compressor 1.
and a relay 1 that controls the operation and air volume switching of the blowers 7 and 8.
Delivered on 7, 18, 1920.21.

Now, when you start operation in cold weather such as winter, room temperature control circuit 1
2 is a relay 1 in order to compare the room temperature TR and the set temperature T8 of the temperature controller 15 and send a heating signal to the output control circuit 16.
7 is excited, and the four-way valve 2 is switched as shown by the broken line.

Then, the relay 19 is energized and the outdoor fan 7 starts operating.

Next, the cold air prevention detection circuit 13 checks whether equations (1) and (2) are established, and if established, outputs an operation signal for the compressor 1 and a stop signal for the indoor blower 8,
Relay 18 is energized by output control circuit 16, relay 20.
21 is controlled to be de-energized.

As a result, the compressor 1 operates in the refrigerant circuit 6 to enter a heating cycle, and the high-temperature, high-pressure refrigerant discharged from the compressor 1 is supplied to the indoor heat exchanger 5.

However, as shown in FIG. 3, at the beginning of operation, the indoor heat exchanger temperature T.

is approximately equal to room temperature TR, and gradually increases as the compressor 1 operates for longer.

At this time, the indoor fan 8 is stopped and there is almost no change in the room temperature.

and indoor heat exchanger temperature T.

When becomes higher than the chamber 'IN T B by a predetermined temperature To,
The cold air prevention cancellation circuit 14 confirms that equation (3) is satisfied and issues a cold air prevention termination command to the output control circuit 16.

Therefore, the output control circuit 16 controls the relays 20 and 21 based on the signal from the room temperature control circuit 12 to control the indoor blower 8.
The air volume is selected in stages to achieve the optimum condition and operation is started.

In this way, in the present embodiment, at the beginning of the heating operation, the room temperature TR is set to a predetermined temperature (for example, the temperature controller 1
5) and the indoor heat exchanger temperature T.

is a predetermined temperature T below room temperature.

When the room temperature is about to get too high, the indoor blower 8 is stopped and pressed to run with a delay, so when the room temperature is higher than the temperature, unnecessary cold air prevention operation is performed to prevent the compressor 1 from operating. It does not prolong the time, and the temperature of the air blown into the room is always T compared to room temperature.

When the temperature rises, the cold air prevention operation is canceled and the air blowing operation is started at the optimal air flow rate corresponding to the room temperature at that time, which is particularly effective in eliminating the discomfort caused by prolonged cold air prevention operation at low temperatures. It is something.

In the above embodiment, in equation (1), the temperature controller 15
The minimum setting temperature T8o was used, but instead of this, (1
) The set temperature Ts of the temperature regulator 15 may also be used as shown in the equation.

In this case, equation (1) will not be satisfied only when the compressor 1 cannot be operated due to the room temperature control circuit 120 command, but in such a situation, the cold air prevention operation command is issued and the indoor fan 8 is stopped. If there is, this will have the effect of preventing the compressor 1 from becoming unable to start due to improper room temperature sensing.

Further, this device can be constructed using one chip or several chips of LSI (Large Scale Integrated Circuit) or a microcomputer.

In the above embodiment, when the compressor 1 starts operating, the operation of the blower 8 is stopped to prevent blowing out of cold air, but it is also possible to prevent the blowing out of cold air by operating at a low speed (the lower the speed, the better). .

In this case, the effect of preventing cold air from blowing is reduced.

As described above, the present invention provides an indoor heat exchanger to which a heating medium from a compressor is supplied, and in which heat is exchanged between the air in the conditioned room using a blower, and the heating operation is performed. T
A temperature detection circuit that detects R and the indoor heat exchanger temperature To, and a temperature T of the conditioned room output from this temperature detection circuit.
A room temperature control circuit that controls the operation of the compressor based on Exchanger temperature T.

) < (conditioned room temperature TR + predetermined temperature T.

), and when both equations hold true, a cold air prevention detection circuit sends out a compressor operation signal and a stop or low speed signal for the indoor fan, giving priority to the signal from the room temperature control circuit. , the operation is started by the output from this cold air prevention detection circuit (indoor heat exchanger temperature T).

)> (conditioned room temperature TR + predetermined temperature To) is equipped with a cold air prevention release circuit that sends a signal to stop the indoor fan or release the low speed signal when the equation (conditioned room temperature TR + predetermined temperature To) is established, so it can be used even when the room temperature is high. Unnecessary cold air prevention operation can be omitted, and cold air prevention operation is performed in a way that is appropriate for the room temperature, and there is no risk of causing discomfort to the occupants due to prolonged cold air prevention time when the room temperature is low, resulting in comfortable heating. The present invention provides a control device for an air conditioner that can be expected to operate and is useful.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a refrigerant circuit of a generally used heat pump type air conditioner, Fig. 2 is a block diagram showing an embodiment of the device of the present invention, and Fig. 3 is a main explanation of the device shown in Fig. 2. It is a diagram. 1...Compressor, 5...Indoor heat exchanger, 3...Indoor blower.

Claims (1)

[Scope of Claims] 1. An indoor heat exchanger to which a heating medium is supplied from a compressor and air in a conditioned room exchange heat using an indoor blower for heating operation. Room temperature TFt and indoor heat exchanger temperature T. and a room temperature control circuit that controls the operation of the compressor based on the conditioned room temperature TR output from the temperature detection circuit and an arbitrary set temperature Ts. )<(minimum set temperature T'so or set temperature T8) and (indoor heat exchanger temperature To)<(
Conditioned room temperature TR + predetermined temperature T. ), and when both equations hold true, a cold air prevention detection circuit sends out a compressor operation signal and a stop or low speed signal for the indoor fan, giving priority to the signal from the room temperature control circuit. , the operation is started by the output from this cold air prevention detection circuit, and (indoor heat exchanger temperature To)>(conditioned room temperature T
R ten predetermined temperature T. A control device for a heat pump type air conditioner, comprising: a cold air prevention cancellation circuit that sends a signal to stop an indoor blower or cancel a low speed signal when the equation () is established.