JPS63217159A - Automatic switching method for cooling heating mode of air conditioner - Google Patents

Abstract

PURPOSE:To prevent the occurrence of malfunction in switch operation between cooling and heating modes due to a momentary fluctuation in temperature in a mask time, by a method wherein, after mask in a first or a second given time is effected, by deciding the temperature of a room to be conditioned, switching between a cooling and a heating mode is performed. CONSTITUTION:When a change-over switch 10 is set to an automatic mode and a switch 9 is depressed to start operation, at an indoor temperature (t) detected by a sensor 13 above a set temperature T of a setter 11, cooling operation in carried out. When an open air temperature decreases to satisfy a condition or t<= T-3.0, a cooling mode is switched to a heating mode. Thereafter, when open air temperature increases again to satisfy a condition of t >= T + 1.5 and is stabilized, after the elapse of a given time of a timer, operation is switched to a cooling mode. As noted above, since a microcomputer 12 switches an operation mode when ¦t-T¦>=1.5 is maintained after the elapse of a given time or a condition or ¦t-T¦>=3.0 is satisfied, a mask motion by a timer is effected during a momentary fluctuation in temperature to prevent erroneous switching of an operation mode. When the width of a fluctuation in temperature is wide, an operation mode is switched irrespective of a mask motion.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an air conditioner having a cooling operation function and a heating operation function, and particularly relates to a method for automatically switching between cooling and heating modes.

(b) Conventional technology The conventional automatic switching technology for heating and cooling modes was developed in 1982.
There was one as described in Japanese Patent No.-72437. The air conditioner described in this publication detects the outside air temperature, and if this outside air temperature is higher than a predetermined set temperature, sets the cooling operation mode, and if this outside air temperature is lower than the set temperature, sets the heating operation mode. It was something. This mode switching was performed periodically at regular intervals based on the outside air temperature that was repeatedly detected at regular intervals from the start of operation. In this way, by resetting the operating mode at regular intervals, it was possible to automatically switch between heating and cooling during the morning, noon, and night of the day.

(c) Problems to be Solved by the Invention In the conventional technology described above, switching between cooling and heating modes was performed based on changes in outside air temperature, but it is necessary to include a temperature detector for detecting outside air temperature. First, there were malfunctions depending on where this temperature sensor was installed. For example, it has been difficult to switch the heating and cooling mode appropriately depending on whether the device is in the sun, in the shade, in a place with good airflow, or in a place with bad airflow.

Additionally, when switching between heating and cooling modes based on outside temperature, the conditions under which the user requires cooling or heating may not match the conditions based on outside temperature because the user is in a conditioned room. In some cases, the heating and cooling mode could not be switched appropriately.

In order to solve these problems, a method as described in Japanese Utility Model Application Publication No. 59-67738 was attempted. The system described in this publication selects the heating and cooling mode based on the difference between the temperature of the room to be conditioned and a desired set temperature. In this case, when the load in the conditioned room changes temporarily,
For example, when a door is opened or closed or the number of users in the room to be conditioned increases or decreases, the heating and cooling mode may change unnecessarily in accordance with the temperature fluctuations in the room to be conditioned.

It is possible to combine the above two conventional techniques to detect the temperature of the conditioned room at regular intervals and reset the heating and cooling mode at regular intervals, but even with such poor performance, the load may be temporarily reduced. If the time when the change occurs coincides with the fixed time, a malfunction may occur as in the case of using the above-mentioned prior art.

In view of these problems, the present invention provides an automatic cooling/heating mode switching method that is based on the temperature in the room to be conditioned and is capable of automatically switching the cooling/heating mode in accordance with the user's experience.

(D) Means for Solving the Problems The present invention provides a method for automatically switching between cooling and heating modes of an air conditioner having a cooling operation function and a heating operation function. and a second temperature that is lower than the set temperature by a second predetermined temperature range to provide a first region above the first temperature and a second region below the second temperature. If the temperature of the room to be conditioned is within the second range, the cooling mode is switched to the heating mode, and if the temperature of the room to be conditioned is within the first range after the second predetermined period of masking in the heating mode. This heating mode is switched to a cooling mode.

(*) Function: In the above-described automatic switching method for heating and cooling modes, the heating and cooling mode can be switched when the temperature of the conditioned room deviates from the desired set temperature by a predetermined temperature or more and this temperature state can be maintained for a predetermined period of time. .

(f) Examples Examples of the present invention will now be described based on the drawings. FIG. 2 is a schematic diagram of an air conditioner using an embodiment of the present invention,
1 is a compressor, 2 is a four-way valve, 3 is an outdoor heat exchanger, 4 is a capillary tube, 5 is an indoor heat exchanger, and 6 is an accumulator, and these elements are sequentially connected in a ring with refrigerant piping. make up the refrigeration cycle. When the four-way valve 2 is in the state shown by the solid line in the figure, the refrigerant discharged from the compressor 1 flows as shown by the solid line arrow, the refrigerant is condensed in the outdoor heat exchanger 3, and the refrigerant is condensed in the indoor heat exchanger 5. The refrigerant evaporates and cools the room. Furthermore, when the four-way valve 2 is in the state shown by the dotted line in the figure, the refrigerant completely discharged from the compressor 1 flows as shown by the dotted arrow, the refrigerant is condensed in the indoor heat exchanger 5, and the refrigerant is condensed in the outdoor heat exchanger 3. The refrigerant evaporates and heats the room.

Note that 7 and 8 are an outdoor fan and an indoor fan, which blow air to the outdoor heat exchanger 3 and the indoor heat exchanger 5, respectively.

FIG. 1 is a main part control circuit diagram used in the refrigeration cycle shown in FIG. 2, and is constructed as follows. Reference numeral 9 denotes a push-button type switch, which outputs a signal to switch between starting and stopping the air conditioner each time it is pressed. Reference numeral 10 denotes a changeover switch, which switches between cooling mode C1 heating mode H5 cooling/heating mode automatic switching C/H1 ventilation mode F. This changeover switch 10 uses a Gray code switch. Reference numeral 11 denotes a room temperature setting device, which determines a desired set temperature. The setting device 11 is composed of a gray code switch, and each code corresponds to 18 to 28 set temperatures.

Reference numeral 12 denotes a microprocessor (microcomputer), which uses, for example, TI's TMS2600 and stores a program based on a flowchart described later. The suppression and setting states of the switch 9, changeover switch 10, and room temperature setting device 11 are as follows:
The signals output from the output ports Rr and Rs of the microcomputer 12 are scanned by the input ports Kl, Kl, Ka, Ka, Jl, and Jl, and are input to the microcomputer 12 and stored in correspondence with specific addresses.

Reference numeral 13 denotes a temperature detector whose internal resistance value changes depending on the temperature, and is provided at a position where it can detect the temperature of the conditioned room. This temperature detector 13 has one end connected to the input port A (analog input terminal) of the microcomputer, and the other end connected to the constant voltage power supply vsi. The microcomputer 12 inputs a current corresponding to the temperature of the room to be conditioned from the input port A every cycle of the program, A/D (analog/digital) converts and stores data values based on this current value.

At this time, this data value is input a plurality of times, the average value is stored as the temperature value of the conditioned room, and temperature control is thereafter performed based on this stored value.

14 to 20 are light emitting elements for displaying room temperature;
°C, 17 °C, 19 °C, 21 °C, 23 °C925 °C, 27
The light emitting element provided at a position corresponding to the degree Celsius scale and corresponding to the scale closest to the temperature value of the conditioned room lights up.

Reference numeral 21 denotes a light emitting element for displaying "cold air prevention", which lights up when the temperature of the indoor heat exchanger 5 shown in FIG. 1 is below a predetermined value during heating operation. This temperature is input from the input port A4 of the microcomputer 12 using the same method as the method for inputting the temperature value of the conditioned room for the temperature detector 22.

23, 24, and 25 are “cooling/heating mode automatic switching” and “
These are light emitting elements for displaying "cooling mode" and "heating mode" and are provided near these display characters.These light emitting elements 23, 24, and 25 are turned on according to the setting value of the changeover switch 10.

Incidentally, when the selector switch 10 is set to the "air blowing mode F11", the light emitting element 24 for displaying the "cooling mode" lights up.

The light emitting elements 14 to 21 and the light emitting elements 23 to 25 are connected to the output ports R0 to R3 of the microcomputer 12 and the display port O.
0 to 0. Lighting is performed using dynamic lighting. Note that 26 to 29 are inverter circuits.

Relays 30 to 33 control the energization of the compressor 1, the indoor blower 8, the outdoor blower 7, and the four-way valve 2 shown in FIG. 1, respectively. These relays 30 to 33 have one end connected to the output port R of the microcomputer 12 via inverter circuits 34 to 37, respectively.

R1m + R+e g Connect to R@, and connect the other end to DC
24[V] is connected to the constant voltage circuit.

An oscillation circuit 38 is composed of a crystal oscillator, a resistor, and a capacitor, and supplies the reference clock of the microcomputer 12 to the input ports 0C8I and 0C82.

In addition, constant voltage Vss, DC24, VAss, V
*! Since a normal power supply circuit can be used as the constant voltage circuit that outputs v, a description thereof will be omitted. Also, the above VASS+
V□ is the upper limit voltage and lower limit voltage of the A/D conversion operation of the microcomputer 12. Further, the terminal INLT is a power reset terminal, and inputs a signal for resetting the microcomputer 12 when the power is turned on. This signal may be one that is output when the output of the power supply circuit exceeds a certain voltage value when the power is turned on.

FIG. 3 is a flowchart of the main part of the microcomputer 12 that operates as described above. The operation will be explained below based on this flowchart. By key scan, switch 9
, selector switch 10. The press or setting state of the room temperature setting device 11 is input. Next, the operating state of the compressor 1 is determined.

That is, timing starts when the compression Ja1 switches from the ON state to the OFF state, this timing is maintained while the compressor 1 is in the OFF state, and when the clock time reaches 2 hours, it is re-initialized and the cooling mode and This erases the memory of the heating mode. If the compressor 1 is operated again within 2 hours of this timing, the timing can be restarted from the time when the compressor 1 is stopped. Next, the temperature of the conditioned room and the coil temperature t.

(Temperature of indoor heat exchanger 5) is input.

Next, if the pressing of the switch 9 is confirmed in the scanning operation, the air conditioner is switched between starting and stopping. This activation is performed after the operation of "operating mode confirmation" as shown in FIG. 4 is performed. This "operation mode confirmation" is to set the cooling/heating mode when the air conditioner starts operating. First, the state of the air conditioner is set from a stopped state to an ON state. Next, it is determined which mode the changeover switch 10 is in, and if it is in the automatic mode, it is determined whether or not there is a memory of the cooling/heating mode, and if there is a memory of the mode, that mode is followed. That is, before reinitialization is performed, the previous operating mode is maintained. If the mode is not stored after re-initialization, the cooling mode or heating mode is set based on the vertical relationship between the temperature T set by the room temperature setting device 11 and the temperature t of the conditioned room.

After the air conditioner starts operating in this manner, the mode of the changeover switch is determined again, and then operation is performed in each mode. During cooling operation, the temperature t of the conditioned room is set to t-10 (
t=10 also when the lowest value of the temperature detection value, a value below this temperature value, is detected. ), the room temperature setting device 11
Since the lowest set temperature is 18°C, the compressor 1 is not driven to perform cooling operation, and essentially only air blowing operation is performed. Also, during heating operation, the indoor heat exchanger 5
Defrosting operation etc. are performed by detecting a change in the temperature t0.

FIG. 5 is a flowchart showing the operation of "mode automatic setting", and the operation is as follows.

First, if the compressor 1 is operating, it continues to perform cooling or heating operation. Compressor 1 is stopped (OFF state)
When this happens, the timer starts counting. Next, when the temperature t of the conditioned room is (set value T) +3°0 or more, that is, “t≧T
+3, 0'', the cooling mode is set regardless of the current operation mode.When t≧T+1.5 and the timer is up, the cooling mode is set in the same way.Also, when t! i;T-3,0'', set the heating mode regardless of the current operation mode, and
t≦T-1,5''' and the timer is time UPL
, set the heating mode in the same way.

The timer is reset and started when the compression flA1 changes from ON to OFF, and the time measured by this timer is set to about 1 hour. In addition, the timer starts counting when the temperature t is t≧T+1°5 or t≦T−1.
, 5, the same effect can be obtained.

In the air conditioner configured as above, selector switch 1
The switching state of the cooling/heating mode when 0 is set to the automatic mode will be explained based on FIG. When the switch 9 is pressed at time h0 to start operation, since the temperature t at this time is higher than the set temperature T, cooling operation is performed. From then until hl, a thermocycle operation is performed in which the temperature t of the conditioned room is compared with the set temperature T. After a short period of time due to a drop in the outside temperature, etc.
), when the temperature t becomes "t≦T-3,0", the operation mode is switched to heating mode and heating operation is started.Subsequently,
Until the time is up, thermocycle operation for heating is performed in the same way as when cooling. From time 0, the outside temperature becomes high again, and the temperature t of the conditioned room satisfies the condition of "t?T+1.5°" and becomes stable.

At this time, when the timer times out at time h4, the operation mode is switched from the heating mode to the cooling mode, and the cooling operation is restarted. In this way, the temperature t of the conditioned room is “It-Tt≧
1.5" is maintained even after a predetermined time, or when the temperature t is "It-TI ≧ 3.0", the operation mode is switched. Therefore, the mask operation by the timer is activated in case of instantaneous temperature fluctuations. Erroneous switching of the operating mode can be prevented.Furthermore, when the temperature fluctuation range is large, the operating mode can be switched regardless of the mask operation of the timer.

In addition, this cooling/heating mode is maintained for a certain period of time after the compressor 1 is stopped, and when the air conditioner or compressor is stopped by operating the switch 9 or the changeover switch 10 and then restarted, the previous operation will be resumed. mode is used.

Further, in this embodiment, the first temperature width and the second temperature width are set to the same temperature range, that is, 1.5 degrees, and the first predetermined time and the second predetermined time are also set to be the same time, that is, about 1 hour. The microcomputer program is simplified, and the number of programs for controlling the public area can be increased, thereby improving the controllability of the air conditioner as a whole.

(G) Effects of the Invention In the automatic switching method of the heating and cooling mode of an air conditioner having a cooling operation function and a heating operation function, a desired set temperature,
a first region having a first temperature higher than this set temperature, a second region having a second temperature lower than this set temperature, and a first region having a first temperature higher than this set temperature;
and a second predetermined time, and if the temperature of the conditioned room is within the second range after the first predetermined time mask in the cooling mode, the cooling mode is switched to the heating mode, and the heating mode is switched to the heating mode. If the temperature of the conditioned room is within the first range after masking for the second predetermined time, the heating mode is switched to cooling mode, so after masking for the first predetermined time or the second predetermined time, Mode switching can be performed, and malfunctions in cooling/heating switching can be suppressed due to instantaneous temperature fluctuations that occur within this mask time.

[Brief explanation of the drawing]

Fig. 1 is an electric circuit diagram of a control device using an embodiment of the present invention, Fig. 2 is a schematic diagram of an air conditioner using the control device shown in Fig. 1, and Figs. FIG. 6 is an explanatory diagram showing the cooling/heating switching operation of the control device shown in FIG. 1. FIG. 9...Switch, 10...Selector switch,
12...Microcomputer.

Claims (5)

[Claims] (1) In an automatic switching method of heating and cooling modes of an air conditioner having a cooling operation function and a heating operation function, a first temperature is higher than a desired set temperature by a first predetermined temperature width and a second temperature lower than the set temperature by a second predetermined temperature width. A first region having a temperature higher than the first temperature and a second region having a second temperature lower than the second temperature are provided using the second temperature, and the temperature of the conditioned room is set to the second region after the first predetermined period of masking in the cooling mode. If the temperature is within the first range, the cooling mode is switched to the heating mode, and if the temperature of the conditioned room is within the first range after the second predetermined period of masking in the heating mode, the heating mode is switched to the cooling mode. A method for automatically switching between heating and cooling modes for an air conditioner. (2) The method for automatically switching heating and cooling modes of an air conditioner according to claim 1, wherein the first predetermined temperature range and the second predetermined temperature range are the same temperature range. (3) The method for automatically switching heating and cooling modes of an air conditioner according to claim 2, wherein the first predetermined time and the second predetermined time are the same time. (4) The first predetermined time period or the second predetermined time period starts when the temperature of the conditioned room reaches the first region or the second region. The method for automatically switching heating and cooling modes of an air conditioner according to item 1. (5) The heating and cooling mode of the air conditioner according to claim 1, wherein the first predetermined time or the second predetermined time starts from the time when cooling or heating is stopped. Automatic switching method.