JPH0452603Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to the operation control of a heat pump type air conditioner, in particular to prevention of cold air at the start of heating operation and after the end of defrosting operation.

(b) Conventional technology In general, the conventional method for preventing cold air is
There was something like the one described in Publication No. 16185. The device described in this publication includes a temperature detection circuit that detects the temperature of an indoor heat exchanger (condenser) and outputs a high temperature output when it reaches a predetermined temperature, and starts operation by the high temperature output of the temperature detection circuit. a first timer that operates after a predetermined time; a second timer that starts operating at the same time as the compressor starts heating operation; and a second timer that operates after a predetermined time; and the operation of the electric motor for the indoor blower is started by the operation of the first timer or the second timer. It was equipped with a motor control means for controlling the motor. In such a configuration, the first timer's time measurement is a few seconds at most, so it is essentially the same as cold air prevention based on the temperature of the indoor heat exchanger, and such control requires the operation of the second timer. In addition to forcibly canceling the cold wind prevention, unnecessary cold wind prevention was prevented.

(c) Problems that the invention aims to solve In the conventional cold air prevention methods described above, the second timer does not operate even if the temperature of the indoor heat exchanger (condenser) is below the temperature that provides a sufficient heating effect. Although the cold air prevention function was canceled and there was no feeling of cold air, there was a problem in that a relatively low level of warm air was being blown out, impairing comfort.

In view of these problems, the present invention provides a cold air prevention device that can efficiently prevent cold air.

(d) Means for solving the problem The present invention consists of a refrigeration cycle consisting of a compressor, a condenser, a pressure reducing device, and an evaporator, a blower device for the condenser that changes the amount of air blown, and an air passage inside the blower device. A cold air prevention device for a heat pump air conditioner having an electric heater provided therein includes a temperature detector for detecting the temperature of the condenser, and a temperature detector for detecting the temperature of the condenser; an air volume control unit that sets the air volume to a small air volume and sets the air volume of the air blower to the set air volume when the detected value is at least a second predetermined temperature higher than the first predetermined temperature; There is a timer unit that outputs a signal after a predetermined time has elapsed, and a signal from this timer unit that outputs an energization signal for the electric heater when the air blower is operated at a small air volume and also outputs an energization signal for the air blower. A control unit that controls operation at a set air volume.

(E) Effect In the cold air prevention device configured as described above, the blower is first operated at a small air volume when the temperature of the condenser is higher than the first predetermined temperature, and then the temperature of the condenser is higher than the second predetermined temperature. When the set amount of air is reached or after a timer has counted a predetermined time, the air volume of the blower is set to the set air volume and the electric heater is energized.

(f) Examples Examples of the present invention will be described below based on the drawings. FIG. 1 is a schematic diagram of a heat pump type air conditioner using the device of the present invention, where 1 is a compressor, 2 is a four-way switching valve, 3 is an indoor heat exchanger, 4 is a capillary reach tube, and 5 is an outdoor side. The heat exchanger 6 is an accumulator, and these are sequentially connected in an annular manner via refrigerant piping to constitute a refrigeration cycle. When the direction of the four-way switching valve 2 is in the state shown by the solid line in the figure, the high-temperature, high-pressure refrigerant discharged from the compressor 1 condenses in the indoor heat exchanger 3 and releases condensation heat to perform heating operation of the conditioned room. After being evaporated in the outdoor heat exchanger 5, it is sucked into the compressor 1 again through the accumulator 6. Furthermore, when the direction of the four-way switching valve 2 is in the state shown by the dotted line in the figure, the high-temperature, high-pressure refrigerant discharged from the compressor 1 condenses in the outdoor heat exchanger 5 and evaporates in the indoor heat exchanger 3. to perform cooling operation in the conditioned room. Reference numeral 7 denotes an indoor air blower, which is provided at a position where air can be blown to the indoor heat exchanger 3. still,
This blower can switch the air volume into three levels: small air volume, medium air volume, and large air volume. Reference numeral 8 denotes an outdoor side blower device, which is provided at a position where air can be blown to the outdoor side heat exchanger 5. Note that this air blower can switch the air volume into two levels: small air volume and large air volume.
Reference numeral 9 denotes an electric heater, which is provided in the air path of the indoor air blower 7.

The compressor 1, four-way switching valve 2, indoor blower 7, outdoor blower 8, and electric heater 9 are controlled by detecting the detected value of the indoor temperature detector 10 and the temperature of the indoor heat exchanger 3. The control device 12 performs this operation based on the detected value of the temperature detector 11.

An electrical circuit diagram of the main parts of this control device 12 is shown in FIG. In this figure, the indoor side blower device 7, the outdoor side blower device 8, the indoor temperature detector 10, and the temperature detector 11, which are the same components as in FIG.

1, 2, and 9 in Figure 2 are the compressor operation relay, four-way switching valve energization relay, and electric heater energization relay shown in Figure 1, but in reality, these relays are not energized. Since this corresponds to the operation or energization of each device, the following explanation will explain these relays as a compressor, a four-way switching valve, and an electric heater.

16 and 17 are resistors, respectively, and the temperature sensor 1
0 and 11, and this connection point is connected to analog input terminals A ₀ and A ₁ of the microcomputer 18 . Since the resistance values of these temperature detectors 10 and 11 change based on the detected temperature, the voltage at these connection points also changes based on the temperature. Microcomputer 18
inputs this voltage from terminals A ₀ and A ₁ and operates the internal A/D (analog/digital) converter at predetermined intervals to convert it into a digital value, and then converts it into a digital value based on this temperature. Remember the value.

Numeral 19 is a push-type switch that closes the contact only when it is pressed, and 20 and 21 are switches that change the open/closed state of the contact each time they are pressed. The switch 19 is for switching the operation/stop of the air conditioner, the switch 20 is for disabling cold air protection when closed, and the switch 21 is a cooling/heating changeover switch that performs heating operation when closed. 2
2 is a gray code switch that changes the air volume of the indoor air blower 7, and can be set to three levels: small air volume, medium air volume, and large air volume. 23 is a gray code switch for setting the room temperature.
It can be set in 1 degree increments from 18 degrees to 30 degrees. The opening/closing or setting states of these switches 19, 20, 21, 22, 23 are determined by the terminals R ₀ , R ₁ ,
Scan the output from R ₂ with terminals K ₀ to K ₃ ,
This microcomputer 12 inputs and stores the information.

Reference numerals 24 and 26 denote air volume control units, which include an AC power supply 25, an indoor air blower 7 (for example, consisting of a single-phase induction motor and a fan), and an outdoor air blower 8 (for example, consisting of a single-phase induction motor and a fan). The amount of air blown can be changed using, for example, phase control, control of applied voltage, switching of the stator winding of the motor, etc. Therefore, the air volume control unit 24 changes the air volume of the indoor air blower 7 in three stages based on the outputs of the terminals R ₃ , R ₄ , and R ₅ of the microcomputer 18 , and the air volume control unit 26 changes the air volume of the indoor air blower 7 in three stages based on the outputs of the terminals R 3 , R 4 , and R ₅ of the microcomputer 18 .
The air volume of the indoor air blower 8 is changed in two stages based on the output of _R7 . Note that 27 and 28 are operating capacitors.

FIG. 3 is a flowchart of the operation of the main part of the microcomputer 18 shown in FIG. 2 (cold air prevention). Note that for other operations, such as a flowchart for cooling operation, a flowchart for heating operation, and a flowchart for defrosting operation, commonly used operations can be used, so detailed explanations will be omitted.

That is, during cooling/heating operation, based on the difference between the room temperature detected by the room temperature detector 10 and the set temperature set by the switch 23, the compressor 1 is turned on/off, the refrigerant flow direction is switched by the four-way switching valve 2, and the blower is turned on. 7 and 8, and defrost operation is performed by the indoor heat exchanger 3 detected by the temperature detector 11.
The process may be performed when the temperature of the area decreases at a certain rate.

In Fig. 3, first the compressor 1 is in the OFF state →
The ON state is determined by whether or not there is an output from terminal _R10 , and compressor 1 is turned OFF.
→Reset the timer only when switched to ON. Next, if the compressor 1 is in the ON state, the timer is counted. Next, when the temperature T of the indoor heat exchanger 3 detected by the temperature detector 11 is "t<25", the indoor blower device 7 is stopped. When "25≦t≦35", if the timer has not timed up (approximately 10 minutes have elapsed), the air volume of the indoor air blower 7 is set to a small air volume. At this time, if the timer is up, the electric heater 9 is energized and the air volume of the indoor air blower 7 is set to the set air volume. When "t≧35", ON/OFF of the electric heater 9 is controlled based on the difference between the room temperature and the set temperature, and the air volume of the indoor air blower 7 is set to the set air volume.

The cold air prevention device configured as described above has a low temperature in the indoor heat exchanger 3 at the start of heating operation or at the start of heating after defrosting operation, so that sufficient heating effect can be achieved even when air is blown. Activates when not available. First, when the compressor 1 starts operating and heating operation starts, the timer starts measuring time. After this, the operation of the blower device 7 is stopped while the temperature of the indoor heat exchanger 3 is lower than 25 degrees. When the temperature of the indoor heat exchanger 3 rises with the operation of the compressor 1 and reaches 25 degrees or higher, the blower device 7 is operated with a small air volume to perform heating operation with a small air volume to suppress the temperature drop in the conditioned room. At this time, the timer will time up (after approximately 10 minutes)
Then, the air blower 7 is operated at the set air volume, and at the same time, the electric heater 9 is energized to perform heating operation while supplementing the low temperature of the indoor heat exchanger 3. This can prevent the heating of the conditioned room from being stopped for a long time. Further, when the temperature of the indoor heat exchanger 3 reaches 35 degrees or higher, the blower is operated at the set air volume to perform normal heating operation.

Furthermore, when the switch 20 shown in FIG. 2 is closed, the cold air prevention described above is bypassed. That is, regardless of the temperature of the indoor heat exchanger 3, the blower device 7 is always operated at the set air volume.

(g) Effects of the invention As described above, the present invention consists of a refrigeration cycle consisting of a compressor, a condenser, a pressure reducing device, and an evaporator, an air blower for the condenser that changes the air flow rate, and an electric circuit installed in the air path of this air blower. In a cold air prevention device for a heat pump air conditioner having a heater, a temperature detector detects the temperature of the condenser, and when the detected value of the temperature detector is equal to or higher than a first predetermined temperature, the air volume of the blower is reduced to a small air volume. and an air volume control unit that sets the air volume of the air blower to the set air volume when the detected value is at least a second predetermined temperature higher than the first predetermined temperature, and starts timing from the time when heating operation by the compressor starts. and a timer unit that outputs a signal after counting a predetermined time, and a signal from this timer unit that outputs an energization signal for the electric heater when the air blower is operated at a small air volume and also controls the operation of the air blower. Since the compressor is equipped with a control unit that sets the set air volume, the maximum time for preventing cold air can be determined by measuring time from the start of operation of the compressor. As a result, the release time of the cold air prevention by the timer can be set short, the heating operation time can be secured for a long time, and the electric heater is energized to suppress the feeling of cold air. In addition, by setting the temperature range for operating the blower at a small air volume, it is possible to operate the heating system with a small air volume, further shortening the period during which heating is not performed and providing comfortable air conditioning.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a heat pump type air conditioner using the device of the embodiment of the present invention, Fig. 2 is an electrical circuit diagram of the main part of the control device shown in Fig.
This is a flowchart of the main parts of the microcomputer shown in the figure. 1... Compressor, 2... Four-way switching valve, 3... Indoor heat exchanger, 4... Capillary reach tube, 5...
...Outdoor heat exchanger, 7...Indoor blower, 9...
...Electric heater, 11... Temperature detector, 18... Microcomputer, 24, 26... Air volume control device.

Claims (1)

[Scope of utility model registration request] Prevention of cold air in a heat pump type air conditioner that has a refrigeration cycle consisting of a compressor, a condenser, a pressure reducing device, and an evaporator, a blower device for the condenser that changes the air flow rate, and an electric heater installed in the air path of this blower device. The device includes a temperature detector that detects the temperature of the condenser, and sets the air volume of the blower to a small air volume when the detected value of the temperature detector is equal to or higher than a first predetermined temperature; an air volume control unit that sets the air volume of the blower to a set air volume at a second predetermined temperature higher than the predetermined temperature; and a timer unit that starts measuring time from the start of heating by the compressor and outputs a signal after measuring a predetermined time. and a control unit that outputs an energization signal for the electric heater when there is a signal from the timer unit and the air blower is operated at a small air volume, and also controls the air blower to operate at a set air volume. Features cold air prevention device for heat pump type air conditioners.