JPH0444985Y2 - - Google Patents

Description

[Detailed description of the invention] <Field of industrial application> The present invention is an air conditioner that operates as a cooler or a heater by switching the direction of refrigerant circulation using a rotary four-way valve. Operation mode confirmation device.

<Prior art> A directional control valve used for switching the operation mode to a conventional air conditioner or heater has a rotary valve and an electromagnet and a permanent magnet in correspondence with the part facing the valve casing, and the magnetism of the electromagnet is There is a rotary type four-way valve that changes the refrigerant circulation direction using a switch, thereby changing the rotation direction of the electromagnet and the permanent magnet relative to each other.

In addition, instead of the rotary four-way valve mentioned above, the force of an electromagnet and a spring is used, and when the power is not energized,
The elasticity of the spring forces the valve body to move in one direction to maintain one operating state, and by energizing the electromagnet, the valve body slides against the elastic force of the spring to maintain another operating state. Some use a spool valve system that allows switching.

<Problems to be solved by the invention> However, with the above-mentioned spool valve system that changes the direction of refrigerant circulation, there is a pressure difference in the refrigerant cycle when switching to cooling operation or from heating to cooling operation. However, since the differential pressure was used to switch and move the valve body, the operation mode was reliably switched, and therefore there were no particular problems with this type of system in terms of switching operation. . On the other hand, the above-mentioned spool valve system has the disadvantage that it is difficult to downsize or is subject to other restrictions.

Furthermore, in a rotary four-way valve, if the pressure acting on the rotary valve is high, the valve body may not be able to rotate due to the pressure. For example, when switching to cooling operation during heating operation, the compressor is temporarily stopped during the switching, and after the restart delay time (3 minutes) has elapsed, the four-way valve is energized and the operation mode is switched. For some reason, the pressure inside the cycle may not have decreased to the point where it can be restarted, even though the four-way valve operation key is in the operation mode switching state (cooling operation). The rotary valve of the four-way valve does not rotate, leading to an abnormal situation where the initial heating operation continues, and if left as it is, an overload condition will occur, an overcurrent will flow, and the power breaker will shut off.

Also, there is a discrepancy between the mode display on the operation panel and the actual operating state of the refrigerant cycle, such as when the heating operation is supposed to be the opposite, but the cooling cycle remains. The present invention aims to eliminate the discrepancy between the mode display on the operation panel and the actual operating state of the refrigerant cycle, and to provide an operation mode confirmation device that enables safe operation.

<Means for solving the problem> A rotary four-way valve that switches the refrigerant circulation direction, a temperature detection circuit that detects the temperature in the refrigerant circulation path, a driver circuit that operates the rotary four-way valve, and a compressor. and a microcomputer that receives detection signals from the temperature detection circuit and operates each driver circuit according to a program.

<Operation> A temperature detection circuit detects the temperature of the pipes on both sides leading to the rotary four-way valve located in the middle of the pipe circulating through the outdoor heat exchanger and the outdoor heat exchanger, and either one of the pipes determined by the operation mode is detected. By using a microcomputer to determine whether the temperature of the pipeline is higher than the specified temperature, the driver circuit determines whether the rotary four-way valve is switching accurately in accordance with the operating mode on the operation panel. If the operation mode on the operation panel corresponds correctly, the compressor will start operating immediately.
In addition, if an accurate response cannot be obtained, the operation mode can be switched after a predetermined standby time, and if an accurate response is still not obtained even after repeating this operation a predetermined number of times, the operation is stopped. .

<Example> Hereinafter, the present invention will be explained in detail with reference to an example shown in the drawings.

As shown in FIGS. 1 to 4, a compressor 1 for compressing and circulating refrigerant is installed in a valve housing 3 of a rotary four-way valve 2.
The holes b and d formed on the same side of the valve housing 3 are connected to the outdoor heat exchanger 8 and the indoor heat exchanger 9, respectively. , 9 through the pressure reducing valve 10, the rotary four-way valve 2, the outdoor heat exchanger 8,
The pressure reducing valve 10 and the indoor heat exchanger 9 are sequentially connected to form a refrigerant circulation path.

The surface of the valve housing 3 in which the through holes a, b, c, and d are formed has a communication groove 71 for switching the through holes c and d to c and b, and a communication groove ₇₁ for switching the through holes a, b to a, A rotary valve body 5 provided with a communication groove ₇₂ for switching to d is pivotally mounted so as to be rotated by a certain allowable angle, and a
Permanent magnets 6 ₁ and 6 _{2 are fixed at an angle of 180°, and the permanent magnets 6 1 and 6 2 are} fixed on the peripheral side of the valve housing 3.
4 electromagnets 4 ₁ , 4 ₂ , 4 corresponding alternately to 6 _2
3 , 4 ₄ are fixed and the rotary valve body 5 is rotated to open each of the through holes a, b, c, d provided on the valve housing 3.
It is formed so that the correspondence communication with it can be changed.

In addition to these configurations, the temperatures at point A on the pipe connecting the rotary four-way valve 2 to the outdoor heat exchanger 8 and at point B on the pipe leading from the rotary four-way valve 2 to the indoor heat exchanger 9 are determined. A temperature detection circuit 13 for measurement, a driver circuit 14 for switching and controlling the rotary four-way valve 2, and a driver circuit 16 for driving and stopping the compressor 1 are connected to each control output terminal of the microcomputer 15. By doing so, the microcomputer 15 can grasp whether the outdoor heat exchanger 8 and the indoor heat exchanger 9 are respectively operating as a heating machine or a cooling machine, and comprehensively control the rotary four-way valve 2 and the compressor 1, respectively. That is.

The microcomputer 15 is preset so that the temperature detection circuit 13 detects the temperature at point A on the pipe after a certain period of time (for example, 2 minutes) has elapsed since the compressor 1 started operating during cooling operation. At the same time, if the detected temperature is 50℃ or higher (any other value obtained experimentally is fine), it is set as normal, and if it is lower than that, it is set as abnormal. Also, during heating operation, the temperature at point B on the pipe line is set to 50℃ ( If the value is higher than the value obtained from the actual measurement, it is normal, and if it is lower than that, it is abnormal. Furthermore, when each of the above abnormalities is detected, compressor 1 is operated for 3 minutes (normal condition). After stopping the compressor 1, the compressor 1 is restarted, and if an abnormality is still detected as a result, the compressor 1 is stopped again in the same manner as above. If such an abnormal condition is repeated three times in a row, a program is set to stop all operations, so that appropriate switching operations are automatically carried out. In addition, the code|symbol 11 in the figure shows an outdoor blower, and 12 shows an indoor blower.

Next, the operation will be explained using the flowchart shown in FIG. 5, but parts unrelated to the operation of the present invention will be omitted. First, in the first step _S1 , a program necessary for automatic operation of the air conditioner is set in the microcomputer 15. Then, in the second step _S2 , the compressor 1 is operated,
Assuming that cooling operation is to be performed in the third step _S3 (in this case, the rotary four-way valve 2 is in the state shown in FIG. 2), the refrigerant is compressed and becomes a high-temperature, high-pressure gas that heats the outdoor heat exchanger 8. At this time, the pipe line from the compressor 1 to the outdoor heat exchanger 8 is also heated, and the microcomputer 15 automatically detects the temperature at point A after 2 minutes using the temperature detection circuit 13, and In step _S4 , it is determined whether the temperature is 50°C or higher, and if it is confirmed that the temperature is higher than the specified temperature, the compressor 1 is allowed to continue operating in a cooling state.
If it is determined that the specified temperature has not been reached, the driver circuit 16 is operated to proceed to step _S6 and the operation of the compressor 1 is stopped. At this time, the compressor 1 is stopped for 3 minutes, and then the driver circuit 14 is operated by the operation of the operation mode changeover switch to rotate the rotary valve body 5 of the rotary four-way valve 2, and the operation mode is changed from the cooling operation state shown in FIG. 4, the correspondence between the communication holes 7 ₁ and 7 ₂ and the communication holes a, b, c, and d is changed, and the refrigerant is circulated as shown by the dotted arrows.

At this time, if the rotary four-way valve 2 has not been switched to the heating side for some reason, that is,
If the operating mode display and the actual operating state do not match, the refrigerant compression cycle remains in the cooling state. Therefore, by determining in step _S5 that the temperature at point B is not 50°C or higher, step S5 is immediately executed.
At _S6 , compressor 1 is temporarily stopped.

Then, after the restart delay time has elapsed, the rotary four-way valve 2 is switched to the heating cycle again. Then, the compressor 1 restarts its operation, and if it is determined that the temperature at point B is not 50° C. or higher after 2 minutes, the compressor 1 is stopped.

In this way, if an abnormality has been determined three times (you can program the required number of times) in step _S7 , the abnormality stop processing routine will be executed in step _S8 , and if no abnormality has been determined by then, The routine returns to step _S9 , the normal processing routine.

<Effects of the invention> The present invention is configured as described above, and when the operation mode is switched from cooling to heating or from heating to cooling during operation, it is checked whether the rotary four-way valve is switching correctly or not by checking the refrigerant circulation pipe. Since it is determined from temperature detection whether the display on the operation mode selector switch and the actual operating state match, abnormal operation can be prevented and excellent effects such as high safety and reliability can be achieved. have

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an air conditioner equipped with the verification device of the present invention, FIG. 2 is a rear view showing the state of the rotary four-way valve used in the air conditioner during cooling operation, and FIG. FIG. 4 is a front view of the rotary four-way valve, FIG. 4 is a back view showing the state of the rotary four-way valve during heating operation, and FIG. 5 is a flowchart of the verification device of the present invention. 1...Compressor, 2...Rotary four-way valve, 3...
... Valve housing, 5 ... Rotating valve body, 8 ... Outdoor heat exchanger,
9... Indoor heat exchanger, 13... Temperature detection circuit, 1
4, 16...driver circuit, 15...microcomputer.

Claims (1)

[Scope of utility model registration request] A rotary four-way valve is provided in the middle of the refrigerant cycle pipe that circulates through the indoor heat exchanger and the outdoor heat exchanger, and switches the direction of recirculation of the refrigerant pumped from the compressor. a temperature detection circuit that detects the temperature in the refrigerant cycle pipe leading to the heat exchanger; a driver circuit that switches the four-way rotary valve; a driver circuit that operates the compressor; and a temperature detection value from the temperature detection circuit. Compare the detected value with a preset reference value, and if the detected value is equal to or higher than the reference value, continue operation in the predetermined mode, and if it does not reach the reference value, stop the operation of the compressor and operate the four-way valve. A microcomputer that inputs a command signal to switch the operation mode to the driver circuit of the four-way valve, and means that selects a temperature detection circuit of a conduit on the refrigerant discharge side from the four-way valve in accordance with the state of the cooling/heating changeover switch. An air conditioner operation mode confirmation device comprising: