JP2956352B2 - Heating and cooling machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating / cooling machine using a compressor.

[0002]

2. Description of the Related Art Conventionally, this type of heating / cooling machine has a configuration as shown in FIG.

That is, 1 is a compressor, 2 is a first check valve provided in a discharge pipe of the compressor 1, 3 is a four-way valve, 4 is an outdoor heat exchanger having a blower 5 for an outdoor heat exchanger, Reference numeral 6 denotes an indoor heat exchanger having an indoor heat exchanger blower 8 provided with an indoor fan motor 7, and 9 denotes an accumulator, which pipes these in order to form a refrigerant circulation path. 10 is a refrigerant heater connected in the middle of the circulation path, 11 is a combustion burner for heating the refrigerant heater 10, 12 is a gas-liquid separator,
3 is a liquid receiver, 14 is a first solenoid valve, and the gas-liquid separator 1
2 is located in a pipe 15 connecting the upper part of the receiver 13. Reference numeral 16 denotes a second check valve, which is located in a pipe 17 connecting a lower part of the liquid receiver 13 and a lower part of the gas-liquid separator 12. Reference numeral 18 denotes a third check valve, which is used for the indoor heat exchanger 6.
And the upper part of the liquid receiver 13. Reference numeral 20 denotes a fourth check valve, which is located in a pipe 22 connecting an upper part of the gas-liquid separator 12 and a pipe 21 connecting the first check valve 2 and the four-way valve 3. Reference numeral 23 denotes a first throttle device, and 24 denotes a second solenoid valve.
3 and the second solenoid valve 24 are connected to the outdoor heat exchanger 4 and the refrigerant heater 1.
It is located in series in a pipe 25 connecting the lower part of the zero.
26 is a third solenoid valve, 27 is a second throttle device, and the third solenoid valve 26 and the second throttle device 27 are pipes 28 connecting the lower part of the gas-liquid separator 12 and the lower part of the refrigerant heater 10.
And a pipe 29 connecting the pipe and the pipe 19. The upper part of the refrigerant heater 10 and the upper part of the gas-liquid separator 12 are connected by a pipe 30. The first solenoid valve 14 and the second solenoid valve 24 are connected by a pipe 31. Further, the control device 32 includes a current detection unit 33 that detects an operation current of the indoor fan motor 7, a current comparison unit 34 that compares the detected operation current with a predetermined current value, Indoor fan motor drive unit 35 for applying a drive voltage to
And a compressor drive unit 38 for driving the compressor 1, and an operation control unit 39 for issuing a command to stop the indoor fan motor 7 and the compressor 1 based on the comparison result of the current comparison unit 34.

In the above refrigerant circuit configuration, the cooling operation switches the four-way valve 3 so that the gas discharged from the compressor 1 flows to the outdoor heat exchanger 4, and opens the second solenoid valve 24 and the third solenoid valve 26. Thus, the first aperture device 23 and the second aperture device 2
Reference numeral 7 denotes a throttle device, and a refrigerant circuit in which the indoor heat exchanger 6 acts as an evaporator. When the heating operation is started, first, a refrigerant recovery operation for recovering the refrigerant in the outdoor heat exchanger 4, the accumulator 9, and the compressor 1 not used as the heating circuit to the heating circuit side is performed. The four-way valve 3 is switched in a direction opposite to that in the cooling operation, and the compressor 1 is operated while the outdoor heat exchanger 4 is connected to the accumulator 9 to operate the outdoor heat exchanger 4, the accumulator 9 and the refrigerant of the compressor 1. To the indoor heat exchanger 6.

[0005] When the cooling operation and the heating operation are started, what is common is that when an instruction for heating or cooling operation is sent to the control device 32 by a remote controller or the like, the indoor fan motor driving unit 3 is activated.
5 gradually applies a voltage to the indoor fan motor 7. or,
The compressor drive section 38 applies a voltage to the compressor 1. At this time, the current detecting means 33 detects the operating current of the indoor fan motor 7, and the detected current value is compared with a predetermined current value which is a current comparing unit 34. And the current comparison unit 3
As a result of the comparison in step 4, if the detected current value is larger than the predetermined current value, the operation control unit 39 issues a stop command to the indoor fan motor drive unit 35 and the compressor drive unit 38, The application of voltage to the fan motor 7 and the compressor 1 is stopped and stopped.

[0006]

However, in the above-described configuration, when the indoor fan motor 7 is locked due to a failure of the blower 8 for the indoor heat exchanger or other causes, an excessive current is supplied to the indoor fan motor 7. Is detected and the indoor fan motor 7 is stopped, so that the indoor fan motor 7 is protected. However, the compressor 1 is operated in an abnormal state such that it is not blown to the indoor heat exchanger 6 until the operation control unit 39 issues a stop command to the compressor drive unit 38 and the compressor 1 stops. The compressor 1 is operated when liquid back occurs or is unnecessary, and the compressor 1
There is a problem that the durability of the rubber is deteriorated.

The present invention solves such a conventional problem. At the start of operation, first, the operation current of the indoor fan motor is detected to determine that there is no abnormality, and then the compressor is driven by driving the compressor. The purpose is to improve durability.

[0008]

In order to solve the above-mentioned problems, a heating / cooling machine according to the present invention has a control device for controlling the operation of an indoor fan motor and a compressor, and the control device comprises Current detecting means for detecting an operating current of the fan motor; a current comparing section for comparing the detected current of the current detecting means with a predetermined current value; and an indoor fan motor driving section for applying a driving voltage to the indoor fan motor And a time integration unit that integrates the time from the start of applying the drive voltage to the indoor fan motor, and the time required from the start of applying the drive voltage to the indoor fan motor until the comparison result is obtained by the current comparison unit. A time comparing unit that compares a predetermined time set for a long time with the time in the time integrating unit; and a comparison result of the time comparing unit that the integrated time of the time integrating unit is larger than the predetermined time. Operation control to send to the indoor fan motor drive unit an instruction to stop driving the indoor fan motor when the current is higher than a predetermined current value based on the comparison result of the current comparison unit. And a part.

[0009]

According to the present invention, the operation current of the indoor fan motor is detected at the time of starting operation, the detected current is compared with a predetermined current value, and the comparison result is obtained. , The compressor can be started smoothly without difficulty.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a system block diagram of the present invention. In FIG. 1, a control device 32 that controls the operation of the indoor fan motor 7 and the compressor 1 includes a current detection unit 33 that detects an operation current of the indoor fan motor 7, and a predetermined predetermined value. A current comparison unit 34 for comparing a current value; an indoor fan motor drive unit 35 for applying a drive voltage to the indoor fan motor 7; and a time integration for integrating the time from the start of applying the drive voltage to the indoor fan motor 7 A predetermined time set to be longer than a time required from when the drive voltage is applied to the indoor fan motor 7 to when the comparison result is obtained by the current comparison unit 34, and a time at the time integration unit 36. Time comparison unit 37 for comparison
When the integration time of the time integration unit 36 is larger than a predetermined time in the comparison result of the time comparison unit 37, the compressor drive unit 38 that drives the compressor 1 and the comparison result of the current comparison unit 34 When the current value is higher than a predetermined current value, the operation control unit 39 sends a command to stop the driving of the indoor fan motor 7 to the indoor fan motor driving unit 35. The same members as those in FIG. 5 showing the conventional example are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 2, the horizontal axis indicates time from the start of operation, and the vertical axis indicates the applied voltage of the indoor fan motor 7, the current of the indoor fan motor 7, and the applied voltage of the compressor 1. 2 shows operation control of the fan motor 7 and the compressor 1. As shown in the upper part of the figure, the voltage applied to the indoor fan motor 7 is
When the voltage is gradually increased, the voltage of the indoor fan motor 7 becomes the set voltage at time t. At this time, the normal current of the indoor fan motor 7 is as indicated by the solid line in the middle of FIG. In the case where the indoor fan motor 7 is in a locked state due to a failure of the indoor heat exchanger blower 8 or the like, the situation is as shown by a dotted line in the middle of FIG. now,
A current value that is smaller than the destruction current C at which the indoor fan motor 7 breaks and that is larger than the operating current B with respect to the set voltage of the indoor fan motor 7 is defined as a predetermined current value A.

Breaking current C> predetermined current value A> operating current B Also, in the abnormal case described above (dotted line in the middle part of the figure), the time until the current of the indoor fan motor 7 reaches the predetermined current value A Is assumed to be t1. In the lower part of the figure, t2 is a time longer than t1, and indicates that the compressor set voltage is applied to the compressor 1 after the start of operation t2. This t2 is a predetermined time.

That is, when a heating or cooling operation command is sent to the control device 32, the indoor fan motor drive unit 35 starts to apply a voltage to the indoor fan motor 7 and the time integration unit 36
Accumulates the time from the start of applying this voltage.
The current detecting means 33 periodically detects the current value of the indoor fan motor 7, and each time, the current comparing section 34 compares the detected current with a predetermined current value A. When the detected current value is smaller than the predetermined current value A and the time of the time integrating unit 36 becomes t2 which is larger than t1 in the comparison result of the time comparing unit 37, the compressor driving unit 38 applies the compressor set voltage to the compressor 1. Then, the compressor 1 is driven.

As a result of the comparison by the current comparing section 34, if the detected current is larger than a predetermined current value A, the operation control section 39
Sends a command to stop driving the indoor fan motor 7 to the indoor fan motor drive unit 35. The changes in the voltage and current applied to the indoor fan motor 7 at this time are as shown by the dotted lines in the upper and middle rows of FIG.

Next, another embodiment of the present invention will be described with reference to FIG. The refrigerant circuit of FIG. 3 is a well-known circuit, and the same members as those of FIG. 1 are denoted by the same reference numerals. The operation and effect of the indoor fan motor and the compressor at the time of the start of the heating / cooling operation are the same as those of FIG.

FIG. 4 shows a flowchart when the above processing flow is realized by a microcomputer.

As described above, the operation current of the indoor fan motor is detected at the start of the operation, the detected current is compared with a predetermined current value, and the comparison result is obtained. If the result is normal, the compressor is driven. This has the effect of improving the durability of the compressor.

[0019]

As described above, according to the heater / cooler of the present invention, the following effects can be obtained.

When the operation is started, first, the current of the indoor fan motor is detected, and it is determined that the current is normal, and then the compressor is driven. In addition, an abnormal time when the indoor fan motor is locked due to a failure of the indoor heat exchanger blower or other causes is determined based on the current value of the indoor fan motor, and at this time, the drive voltage is applied to the indoor fan motor and the compressor. Therefore, there is no liquid back in the compressor, the durability of the compressor is improved, and the safe operation can be guaranteed.

[Brief description of the drawings]

FIG. 1 is a system block diagram of a control device of a heating / cooling machine according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing a relationship between a voltage applied to an indoor fan motor, a current, and a voltage applied to a compressor with respect to time from the start of operation.

FIG. 3 is a system block diagram of a control device of a heating / cooling machine according to another embodiment of the present invention.

FIG. 4 is a flowchart showing a processing flow of a microcomputer according to an embodiment of the present invention.

FIG. 5 is a system block diagram of a control device of a heating / cooling machine in a conventional example.

[Description of Signs] 1 Compressor 4 Outdoor heat exchanger 6 Indoor heat exchanger 7 Indoor fan motor 8 Blower for indoor heat exchanger 23 First throttle device 27 Second throttle device 32 Control device 33 Current detection means 34 Current comparison Unit 35 Indoor fan motor drive unit 36 Time integration unit 37 Time comparison unit 38 Compressor drive unit 39 Operation control unit

Claims (1)

(57) [Claims] 1. A refrigerant circuit comprising a compressor, an indoor heat exchanger having an indoor fan motor for driving a blower for an indoor heat exchanger, an outdoor heat exchanger, and a throttling device, wherein the indoor fan motor and the compressor A control device for controlling the operation of the indoor fan motor, the control device comprising: a current detection unit configured to detect an operation current of the indoor fan motor; and a current comparison unit configured to compare a detection current of the current detection unit with a predetermined current value. Unit, an indoor fan motor drive unit that applies a drive voltage to the indoor fan motor, a time integration unit that integrates the time since the start of applying the drive voltage to the indoor fan motor, and a drive voltage to the indoor fan motor. A time comparison unit that compares a predetermined time set longer than a time required until a comparison result is obtained in the current comparison unit after the application starts and a time in the time integration unit, When the integration time of the time integration unit is larger than a predetermined time in the comparison result of the time comparison unit, a compressor driving unit that drives the compressor, and a current value higher than a predetermined current value in the comparison result of the current comparison unit. A heating / cooling unit having an operation control unit that sometimes sends a command to stop the driving of the indoor fan motor to the indoor fan motor driving unit.