JP2867691B2 - Heating and cooling machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a warming / cooling machine that uses a compressor during cooling and uses a refrigerant conveying means and a refrigerant heater other than the compressor during heating. is there.

2. Description of the Related Art Conventionally, this kind of heating / cooling machine has a configuration as shown in FIG. 4 as disclosed in, for example, Japanese Patent Application Laid-Open No. 57-101263.

That is, the compressor 1 having the compressor heater 2,
Four-way valve 3, outdoor heat exchanger 4 having outdoor heat exchanger fan 5, first electromagnetic valve 6, capillary tube 7, indoor heat exchanger 8 having indoor heat exchanger fan 9, second electromagnetic valve 1
The cooling circuit is formed by annularly piping the check valve and the accumulator 12. The third solenoid valve 13 and the refrigerant pump 1
4. A circuit in which a refrigerant heater 15 having a burner 16 is connected in series is connected at one end between the capillary tube 7 and the indoor heat exchanger 8, and at the other end between the second solenoid valve 10 and the indoor heat exchanger 8. Connected to In the above configuration, the outdoor heat exchanger 4 is used as a condenser and the indoor heat exchanger 8 is used as an evaporator to form a cooling cycle by operating the compressor 1. In the heating operation, the refrigerant heater 15 is heated by the burner 16. By doing so, an indoor heat exchanger 8 is also used as a condenser, a refrigerant pump is used as a refrigerant conveying means to constitute a heating cycle, and the compressor 1 is heated by the compressor heater 2 to prevent the refrigerant from staying in the compressor 1. Heat to maintain a constant temperature.

With the above configuration, at the start of the heating operation, the first solenoid valve 6 is closed, and the four-way valve 3 is switched so that the refrigerant gas discharged from the compressor 1 flows to the indoor heat exchanger 8. Is stopped and the outdoor heat exchanger 4 by the compressor 1 is stopped.
After performing the refrigerant recovery operation from the circuit for a certain period of time, the operation of the refrigerant pump 14, the refrigerant heater 15, and the fan 9 for the indoor heat exchanger is started, and the compressor 1 is stopped.

However, in the above-described configuration, the refrigerant recovery operation is always performed for a certain period of time. Therefore, when the amount of the refrigerant leaking into the outdoor heat exchanger 4 is small, the refrigerant recovery is performed immediately. The operation of the compressor 1 is continued even when the operation is stopped. Therefore, the compressor 1 continues to operate with almost no refrigerant, and the temperature of the motor winding of the compressor 1 rises, and in some cases, the motor winding of the compressor 1 is disconnected and the compressor is disconnected. 1 has been stopped or the durability of the compressor 1 has been deteriorated.

An object of the present invention is to solve such a conventional problem, and it is an object of the present invention to recover a refrigerant to a heating circuit side for a necessary time at the start of a heating operation, thereby enabling a stable heating operation.

Means for Solving the Problems In order to solve the above problems, the air conditioner of the present invention is configured such that a refrigerant circuit other than a compressor during heating, a refrigerant heater, and an indoor heat exchanger constitute a refrigerant circuit, Temperature detecting means for detecting the temperature on the high pressure side of the compressor, refrigerant recovery means for recovering the refrigerant of the outdoor heat exchanger to the indoor heat exchanger by driving the compressor, and controlling the driving of the refrigerant recovery means A control device, wherein the control device detects that a set time has elapsed from the start of driving of the refrigerant recovery unit, and outputs a set time detection unit, and a detection temperature of the temperature detection unit is equal to or higher than a set temperature A set temperature detector for detecting and outputting
Having a refrigerant recovery control unit that drives the refrigerant recovery means,
The refrigerant recovery operation is performed at the time of starting the heating operation for the shorter of the time for the set time detection unit to detect that the set time has elapsed and the time for the set temperature detection unit to detect that the temperature has exceeded the set temperature. It is configured.

Operation With the above configuration, the present invention compares the time until the temperature on the high-pressure side of the compressor reaches the set temperature with the set time as the refrigerant recovery operation time at the start of the heating operation, and determines the shorter time. Therefore, the refrigerant recovery operation required for the heating operation can be performed safely and reliably.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a system block diagram of the present invention. First
In the figure, reference numeral 1 denotes a compressor heater 2 provided at a lower portion.
, 3 is a first check valve provided in a discharge pipe of the compressor 1, 4 is a four-way valve, 5 is a blower for an outdoor heat exchanger 6
, An indoor heat exchanger having an indoor heat exchanger blower 8, and a circulation path formed by piping in the order of an accumulator. 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, 13 is a liquid receiver, and 14 is a first solenoid valve for gas-liquid. It is located in a pipe 15 connecting the upper part of the separator 12 and the upper part of the receiver 13. 16 is the second check valve
The lower part of 13 is located in a pipe 17 connecting the lower part of the gas-liquid separator 12. Reference numeral 18 denotes a third check valve, which is located in a pipe 19 connecting the indoor heat exchanger 7 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 portion of the gas-liquid separator 12 and a pipe 21 connecting the first check valve 3 and the four-way valve 4. 23 is a first capillary tube, 24 is a second solenoid valve, and the first capillary tube 23 and the second solenoid valve 24 are pipes connecting the outdoor heat exchanger 5 and the lower part of the refrigerant heater 10.
Position in series in 25. 26 is a third solenoid valve, 27 is a second capillary tube, and the third solenoid valve 26 and the second capillary tube 27 are pipes 28 connecting the lower part of the gas-liquid separator 12 and the lower part of the refrigerant heater 10. Pipe 29 connecting pipe 19
It is located in series inside. The upper part of the refrigerant heater 10 and the upper part of the gas-liquid separator 12 are connected by a pipe 30. First solenoid valve 14
And the second solenoid valve 24 are connected by a pipe 31.

In the above refrigerant circuit configuration, the cooling operation is performed by switching the four-way valve 4 so that the discharge gas of the compressor 1 flows to the outdoor heat exchanger 15 and opening the second solenoid valve 24 and the third solenoid valve 26.
A refrigerant circuit in which the capillary tube 23 and the second capillary tube 27 are used as expansion devices and the indoor heat exchanger 7 functions as an evaporator. In the heating operation, the four-way valve 4 is switched in the direction opposite to that in the cooling operation.
By heating the refrigerant in the refrigerant heater 10 is heated,
The gas-phase refrigerant, which has become hot in the gas-liquid separator 12, is
22, the refrigerant liquid which is pushed out to the indoor heat exchanger 7 through the check valve 20 and the four-way valve 4 and radiates heat in the indoor heat exchanger 7 to perform indoor heating and liquefies through the pipe 19 and the check valve 18 It moves into the receiver 13. The refrigerant liquid accumulated in the receiver 13 is supplied to the first solenoid valve 14.
By opening the valve, the pressure of the gas-liquid separator 12 is led, so that the second check valve 16
Is returned to the gas-liquid separator 12. As described above, the opening / closing operation of the liquid receiver 13 and the first solenoid valve 14 and the check operation of the third check valve 18 allow the heat transfer medium to be performed without the operation of the compressor 1. . That is, the liquid receiver 13 and the first solenoid valve
The 14 and the third check valve 18 constitute the refrigerant conveying means 32.

Before performing the heating operation, a refrigerant recovery operation of recovering the refrigerant in the outdoor heat exchanger 5, the accumulator 9, and the compressor 1 that is not a heating circuit to the heating circuit side is performed. With the four-way valve 4 in the same direction as in the heating operation, the compressor 1 is operated in a state where the outdoor heat exchanger 5 is in communication with the accumulator 9, and the refrigerant in the outdoor heat exchanger 5, the accumulator 9 and the refrigerant in the compressor 1 is converted into indoor heat. Collected in exchanger 7. At this time, the blower 8 for the indoor heat exchanger is operated to sufficiently liquefy the refrigerant in the indoor heat exchanger 7 and to easily return the liquid refrigerant from the pipe 19 to the receiver 13. That is, the compressor 1, the first check valve 3, and the four-way valve 4 use the refrigerant recovery means 33.
Is configured. 34 is a temperature detecting means for detecting the temperature on the high pressure side of the compressor 1, 35 is a control device for controlling the refrigerant collecting means 33, 36 is a refrigerant collecting control unit for driving the refrigerant collecting means 33, and 37 is a refrigerant collecting means. A set time detecting unit that detects that a set time has elapsed from the start of driving of 33 and outputs the detected temperature. Is a set temperature detection unit that detects and outputs a set temperature.

When performing a refrigerant recovery operation (driving the refrigerant recovery means 33) for recovering the refrigerant included in the outdoor heat exchanger 5, the accumulator 9, and the compressor 1 to the heating circuit side, which is not a heating circuit, the refrigerant recovery amount and the compression are reduced. The temperature of the machine 1 is as shown in FIG. That is, the horizontal axis represents the refrigerant recovery operation time,
The vertical axis shows the refrigerant recovery amount and the temperature of the compressor 1 at that time,
Change in refrigerant recovery amount with respect to refrigerant recovery operation time and compressor 1
FIG. In the figure, the solid line indicates a case where the amount of refrigerant leaking to the outdoor heat exchanger 5, the accumulator 9, and the compressor 1 which is not a heating circuit is large, and the dotted line indicates a case where the amount of refrigerant leakage is small. Also, as can be seen from the figure, the refrigerant recovery amount increases with the refrigerant recovery operation time, but after most of the refrigerant has been recovered, the refrigerant recovery amount does not change. Further, the temperature of the compressor 1 gradually rises with the refrigerant recovery operation time, but rapidly rises after most of the refrigerant is recovered. Now, the set time of the refrigerant recovery operation performed by driving the refrigerant recovery means 33 is set to T with reference to the case where the leakage amount is large (the solid line in FIG. 2).
The temperature of the compressor at this time is a temperature determined from the guarantee of the durability and reliability of the compressor (this temperature is defined as a set temperature t,
To guarantee the compressor, it must be lower than this t). On the other hand, when the leakage amount is small, as shown by the dotted line in FIG. 2, the refrigerant recovery operation time is T 'and the refrigerant recovery is almost completed. Here, if the refrigerant recovery operation is further continued until the set time T, the temperature of the compressor becomes t ', which is higher than the temperature t determined by guaranteeing the durability and reliability of the compressor. Therefore, in this case, when the temperature of the compressor 1 reaches the set temperature t (the refrigerant recovery operation time is T ″), the refrigerant recovery operation (drive of the refrigerant recovery means 33) is stopped.

Thus, whether the refrigerant recovery operation time has reached the set time based on the case where the leakage amount is large during the refrigerant recovery operation,
Alternatively, by detecting whether the temperature of the compressor is equal to or higher than the guaranteed temperature of the compressor, it is possible to reliably recover the refrigerant and prevent the compressor from overheating, so that the heating operation can always be stabilized.

FIG. 3 is a flowchart in the case where the above processing flow is realized by a microcomputer.

Effects of the Invention As described above, according to the heating / cooling device of the present invention, the following effects can be obtained.

(1) During the refrigerant recovery operation, even if the amount of refrigerant leaking to the outdoor heat exchanger, the accumulator, the compressor, etc., which is not a heating circuit, is small, the temperature of the compressor can be kept below the guaranteed temperature of the compressor. This prevents overheating of the compressor and improves durability and reliability.

(2) The refrigerant recovery operation is not always performed for a certain period of time (the time when the refrigerant can be recovered even when the leakage amount is large) regardless of whether the amount of leakage is large or small. The time required for the temperature to reach the set temperature is compared with the set time, and the refrigerant recovery operation is performed at the start of the heating operation for the shorter time. Fast startup and reduced power consumption.

[Brief description of the drawings]

FIG. 1 is a system block diagram of a control device of a heating / cooling device in one embodiment of the present invention, FIG. 2 is a characteristic diagram showing a relationship between a compressor temperature and a refrigerant recovery amount with respect to a refrigerant recovery operation time, and FIG. FIG. 4 is a flow chart showing the processing flow of the microcomputer, and FIG. 4 is a block diagram for explaining a conventional example. 1 ... Compressor, 5 ... Outdoor heat exchanger, 7 ... Indoor heat exchanger, 10 ... Refrigerant heater, 32 ... Refrigerant conveying means, 33 ... Refrigerant collecting means, 34 ... Temperature detecting means 35 ... Control device, 36
…… Refrigerant recovery control section, 37 …… Set time detection section, 38 …… Set temperature detection section.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F25B 1/00

Claims (1)

(57) [Claims] A refrigerant circuit comprising a compressor, an indoor heat exchanger, an outdoor heat exchanger, and a throttling device during cooling, and a refrigerant conveying means other than the compressor, a refrigerant heater, and an indoor heat exchanger during heating. A refrigerant circuit configured by, a temperature detecting means for detecting the temperature of the high pressure side of the compressor, a refrigerant recovery means for recovering the refrigerant of the outdoor heat exchanger to the indoor heat exchanger by driving the compressor, A control device for controlling the driving of the refrigerant recovery means, wherein the control device detects that a set time has elapsed from the start of driving the refrigerant recovery means, and outputs a set time detection unit; and a detection temperature of the temperature detection means. Has a set temperature detecting section for detecting that the temperature has become equal to or higher than a set temperature, and a refrigerant recovery control section for driving the refrigerant collecting means, and the set time detecting section detects that a set time has elapsed. Time and temperature setting Heating and cooling machine that is configured to perform the refrigerant recovery operation only during the heating operation start shorter time of the time for detecting that the part is greater than or equal to the specified temperature.