JPH05215349A - Heat transfer device - Google Patents

Abstract

PURPOSE:To provide a heating operation for performing s stable refrigerant heating against a leakage of refrigerant into a cooling circuit while a heat transfer power during the heating operation being quite low in its value in a heat transfer device in which the heat is utilized for the heating operation under utilization of an increased pressure when the refrigerant is heated. CONSTITUTION:A heat transferring part 9 having a refrigerant heater 1, a gas-liquid separator 2, a liquid receiver 4, the first check valve 5 and the first opening or closing valve 7 is provided with a heating circuit 10 in which the gas-liquid separator 2, an indoor heat exchanger 12, the second check valve 14 and the liquid receiver 4 are connected by a pipe in sequence; a cooling circuit 21. having an outdoor heat exchanger 23 additionally connected at its one end to the heating circuit 10 through a channel changing-over valve 26 and at the other end to the heating circuit 10 through the second opening or closing valve 25; and a control device for changing the action of the refrigerant when the combustion is started with the elapsing time continued to the next heating operation start time after the stopping of the heating operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat transfer device for utilizing heat for heating or the like by utilizing a pressure increase when heating a refrigerant.

[0002]

2. Description of the Related Art Conventionally, as a heat transfer device for heating by this kind of refrigerant heating, for example, JP-A-57-101263.
There is a structure as shown in FIG.

That is, the compressor 41, the flow path switching valve 42, the outdoor heat exchanger 44 having the outdoor blower 43, and the first solenoid valve 4
5, a capillary tube 46, an indoor heat exchanger 48 having an indoor blower 47, a second electromagnetic valve 49, a check valve 50, and an accumulator 51 are sequentially pipe-connected to form a circulation path, and further a third electromagnetic valve 52 and a refrigerant. Refrigerant is enclosed as a working medium in a circuit in which a series piping circuit in which a refrigerant heater 55 having a pump 53 and a burner 54 is connected in series is connected between a downstream of the capillary tube 46 and an upstream of the second electromagnetic valve 49. There is.

In the heating operation, after the pumping operation in which the compressor 41 is driven to move the refrigerant on the outdoor heat exchanger 44 side to the refrigerant heater 55 side, the refrigerant heater 55 is heated by the burner 54 to form an evaporator. The indoor heat exchanger 48 is used as a condenser, the refrigerant pump 53 is used as a refrigerant carrier, and a heating cycle is configured. Further, the cooling is a compressor-driven conventional cooling cycle.

Further, as another conventional heat transfer device for heating by heating a refrigerant, cooling is performed by a conventional method of driving a compressor, and heating is performed by using this cooling compressor as a refrigerant gas pump (not shown). There is.

[0006]

However, in the above-mentioned conventional configuration, the refrigerant pump or the compressor must be driven as the conveying means for circulating the refrigerant during the heating operation, and a relatively large electric input as the heat conveying power. (When the heating capacity is about 4000 kcal / h, 50-60 with the refrigerant pump.
W, the compressor consumes about 300 to 400 W), and there is a problem that heating running cost becomes high.

The present invention solves such a conventional problem, in which the heat transfer power during heating is extremely small, and the heating operation is performed by stable heating of the refrigerant against the leakage of the refrigerant into the cooling circuit. The purpose is to provide.

[0008]

In order to achieve the above object, the present invention connects a refrigerant heater and a gas-liquid separator, and connects the gas-liquid separator to the inlet side and the outlet side by a first opening / closing valve and a first check valve. A heating circuit in which the gas-liquid separator, the indoor heat exchanger, the second check valve, and the liquid receiver are sequentially pipe-connected to the heat transfer section that is respectively connected via a valve, and one end is connected via a flow path switching valve to the other. An end has a cooling circuit having an outdoor heat exchanger and a compressor additionally connected to the heating circuit via a second on-off valve, and a refrigerant behavior at the start of combustion according to the elapsed time from the stop of heating to the start of the next heating. A control device for changing the control means is provided.

[0009]

According to the present invention, with the above configuration, the refrigerant is conveyed by repeating the opening / closing operation of the first opening / closing valve which requires only a very small electric input to reduce the running cost, and the time elapses after the heating is stopped until the next heating is started. With the amount of refrigerant leaking into the cooling circuit that increases along with it, and the liquid refrigerant distribution in the heating circuit that changes over time, the refrigerant behavior control means is optimally changed to keep the liquid refrigerant in the refrigerant heater at the start of heating. Secure.

By securing this liquid refrigerant, abnormal overheating of the refrigerant heater at the start of combustion can be prevented, and stable heating operation by heating the refrigerant can be realized.

[0011]

Embodiment An embodiment of the present invention will be described below with reference to FIG.

Reference numeral 1 is a refrigerant heater having an overheat detector 1a provided on the wall surface, 2 is a gas-liquid separator, and the refrigerant heater 1 and the gas-liquid separator 2 are inlet pipes 3 and outlet pipes 3'in an annular pipe line. It is connected. Reference numeral 4 denotes a liquid receiver provided above the gas-liquid separator 2, 5 denotes a first check valve provided in a drop pipe 6 connecting the liquid receiver 4 and the gas-liquid separator 2, and 7 denotes the liquid receiver 4 and the gas. A first opening / closing valve provided in a pressure equalizing pipe 8 connecting to the liquid separator 2, 9 is a heat having a refrigerant heater 1, a gas-liquid separator 2, a liquid receiver 4, a first check valve 5, and a first opening / closing valve 7. The transport unit 10 connects the gas-liquid separator 2 and the indoor heat exchanger 12 having the indoor blower 11 with the gas refrigerant pipe 13, and the indoor heat exchanger 12 and the liquid receiver 4 are connected.
Is a heating circuit in which the second check valve 14 provided in the vicinity of the inlet upstream side and the liquid receiver 4 are connected by a liquid refrigerant pipe 15 to form a heat transfer section 9 and an annular circulation path. Reference numeral 16 is a third check valve provided on the gas-liquid separator 2 side of the gas refrigerant pipe 13, and 17 is a refrigerant heater 1.
, 18 is a fuel supply device for varying the fuel supply to the burner 17, 19 is an evaporation temperature detector provided on the refrigerant outlet side of the refrigerant heater 1, and 20 is an indoor heat exchanger 12. It is a room temperature detector that detects the temperature of the provided inflow air side.

Reference numeral 21 is a cooling circuit having a compressor 22, an outdoor heat exchanger 23, a first pressure reducing device 24, and a second opening / closing valve 25, one end of which is connected to the gas refrigerant pipe 13 via a flow path switching valve 26. At the same time, the discharge pipe 27 of the compressor 22 is connected via a fourth check valve 28 between the third check valve 16 of the gas refrigerant pipe 13 and the flow path switching valve 26 composed of a four-way valve. The other end of the cooling circuit 21 communicates with the refrigerant heater 1 and the pressure equalizing pipe 8. Reference numeral 29 is a second cooling circuit that connects the inlet pipe 3 and the liquid refrigerant pipe 15 and has a third opening / closing valve 30 and a second pressure reducing device 31. 32 is a liquid side service valve provided in the liquid refrigerant pipe 15, 33 is a gas side service valve provided in the gas refrigerant pipe 13, 34 is a liquid side joint provided on the indoor heat exchanger 12 side of the liquid refrigerant pipe 15, and 35 is A gas-side joint provided on the indoor heat exchanger 12 side of the gas refrigerant pipe 13, the liquid-side and gas-side service valves 32 and 33, and the liquid-side and gas-side joint 34,
Between 35, the length of the connecting refrigerant pipe can be arbitrarily set according to the installation distance between the outdoor side and the indoor side.

Reference numeral 36 is an outdoor blower provided in the outdoor heat exchanger 23, and 37 is an overheat detector 1a, a first opening / closing valve 7, a fuel supply device 18, an evaporation temperature detector 19, a room temperature detector 20,
The control device is electrically connected to the compressor 22 and the second on-off valve 25, and controls the refrigerant behavior at the start of combustion according to the elapsed time from the stop of heating to the start of the next heating.

In the above structure, the heating is performed by the refrigerant heater 1.
The liquid refrigerant heated by the heat of combustion in the burner 17 flows into the gas-liquid separator 2 in a gas-liquid two-phase state, and the liquid refrigerant flows into the refrigerant heater 1 again from below the gas-liquid separator 2. On the other hand, the gas-liquid separated gas refrigerant flows into the indoor heat exchanger 12 through the gas refrigerant pipe 13, and the refrigerant radiated to the indoor side by the operation of the indoor blower 11 is condensed and liquefied to become a supercooled liquid. When the first opening / closing valve 7 of the pressure equalizing pipe 8 communicating with the liquid receiver 4 is closed by the control device 37, the supercooled liquid pushed by the evaporation pressure in the refrigerant heater 1 passes through the second check valve 14. When the refrigerant slightly flows into the liquid receiver 4, the saturated gas refrigerant in the liquid receiver 4 is cooled and condensed by the supercooled liquid, and the new supercooled refrigerant is received by the rapid depressurizing action at the time of the condensation. It flows all at once until the inside of the container 4 becomes full. Next, when the first opening / closing valve 7 is opened by the control device 37, the pressures of the liquid receiver 4 and the gas-liquid separator 2 are communicated with each other by the pressure equalizing pipe 8 to have the same pressure, and the liquid refrigerant in the liquid receiver 4 is gravitated due to gravity The refrigerant falls on the separator 2 and the refrigerant is supplied to the refrigerant heater 1. If an electromagnetic valve is used as the first opening / closing valve 7, the power for carrying the refrigerant to circulate may be only the power consumption of the electromagnetic valve, and the opening / closing operation of the electromagnetic valve having a rated input of about 7 W will effectively bring about 3 to 4 Wh. Refrigerant can be circulated with a small amount of transportation power.

In FIG. 2, it is detected that the room temperature detector 20 has fallen below the set value from the thermo-OFF state in which the combustion of the burner 17 is stopped and the heating is stopped by detecting that the room temperature detector 20 has reached the set value. The change in the refrigerant behavior control due to the increase in the elapsed time from the start of combustion of the burner 17 to the start of heating to start the heating is shown.

In FIG. 2, at the time t ₁ , the combustion is stopped by the thermo OFF and the heating is stopped, and a short elapsed time Δt
After _{1 and} the thermostat is turned on, the heating is started by the combustion start by the first control by the opening / closing operation of the first opening / closing valve 7 at time t ₂ . Next, at time t ₃ , heating is stopped by turning off the thermostat, and if heating is started by turning on the thermo after a long elapsed time Δt ₂ (Δt ₂ > Δt ₁ ), the second opening / closing valve 25 is activated before the start of combustion at time t _4. Opening for a short time (about 10 seconds) and compressor 2
The gas refrigerant in the refrigerant heater 1 is caused to flow to the outdoor heat exchanger 23 side by the second control in which the gas purge activation by the short-time operation 2 (about 30 seconds) is added to the opening / closing operation of the first opening / closing valve 7.
Instead, the liquid refrigerant is drawn into the refrigerant heater 1 and a gas purge activation is added to recover the refrigerant that has leaked to the outdoor heat exchanger 23 side to the heating circuit.

Further time t_FiveHeating by turning off the thermostat
Stopped and very long elapsed time Δt₃(Δt₃> Δt
₂> Δt₁), And if heating is started with thermo ON,
Interval t ₆Pump by operation of the compressor 22 before starting combustion at
Refrigerant leaked to the outdoor heat exchanger 23 side due to down (about 3 minutes)
Is recovered in the heating circuit and then the second on-off valve 25
The opening of the compressor (about 10 seconds) and the operation of the compressor (about 30 seconds)
The above-mentioned gas purge activation by
In addition.

As described above, the behavior of the refrigerant is changed depending on the elapsed time from the combustion stop to the combustion start. First, the pressure difference in the heating circuit decreases due to the combustion stop, and the pressure difference between the cooling circuit and the dormant cooling circuit is small. The second on-off valve 25, the fourth
This is because the amount of refrigerant leakage in the valve portion that separates the heating circuit and the cooling circuit, such as the check valve 28 and the flow path switching valve 26, becomes large, especially when a four-way valve is adopted as the flow path switching valve 26. Become.

Secondly, in addition to stopping combustion, the evaporation pressure of the refrigerant is reduced, the degree of supercooling of the liquid refrigerant is reduced, and the circulation action of the liquid refrigerant due to the opening / closing operation of the first opening / closing valve 7 is weakened to stop. This is because the residual heat of the refrigerant heater 1 causes the liquid refrigerant in the refrigerant heater 1 to evaporate and decrease, and to completely evaporate over time.

With respect to the natural behavior of the refrigerant when the combustion is stopped, the behavior of the refrigerant at the start of combustion is changed with the passage of time, and at the short elapsed time Δt ₁ , there is little refrigerant leakage and a large amount of liquid refrigerant. Since it is distributed in the heater 1, it is sufficient to operate only the first opening / closing valve 7, and the next long elapsed time Δt.
_{In the case of 2} , the leakage of the refrigerant to the cooling circuit is still small, but the liquid refrigerant in the refrigerant heater 1 is reduced by the residual heat, so that only the gas purge start to forcibly draw the liquid refrigerant into the refrigerant heater is sufficient. Further, at a very long elapsed time t ₃ , the refrigerant often leaks into the cooling circuit, and the distribution of the liquid refrigerant is uncertain, so that the refrigerant is recovered to the heating circuit by pump down, and the recovered refrigerant collects the liquid refrigerant pipe 15 side. Is distributed so as to be filled with the liquid, and then the liquid refrigerant is drawn into the refrigerant heater 1 by starting the gas purge.

As described above, for any elapsed time, liquid refrigerant is secured in the refrigerant heater at the start of combustion to prevent abnormal overheating in the refrigerant heater, thermal decomposition of the refrigerant, thermal deterioration of the refrigerant heater, etc. Can be prevented and the reliability and durability of the device can be improved.

Further, since the operation of the compressor having a large electric input is suppressed to the minimum, the economical efficiency is improved.

Needless to say, even when the heating is turned on by the switch after a lapse of time after the heating is turned off by an external switch such as a remote controller (not shown), the thermo-on after the thermo-off can be considered. Yes.

Further, since the remote control may be turned off during the thermostat is turned off, the elapsed time from the heating stop to the heating start may be more practical and appropriate to be the elapsed time from the combustion stop to the combustion start. More effective on refrigerant behavior.

For cooling, the flow path switching valve 26 is switched in the direction of the broken line in FIG. 1, the second opening / closing valve 25 and the third opening / closing valve 30 are opened, and the compressor 22, the indoor blower 11 and the outdoor blower 36 are opened.
In this way, the conventional compressor-driven cooling is performed.

[0027]

As described above, the heat transfer device of the present invention includes a heating circuit in which an indoor heat exchanger is connected to a heat transfer portion having a refrigerant heater, a liquid receiver, and a first check valve, and this heating circuit. According to the elapsed time from the stop of heating to the start of the next heating, the cooling circuit having the outdoor heat exchanger and the compressor additionally connected at one end via the flow path switching valve and at the other end via the second opening / closing valve Since the control device that changes the behavior of the refrigerant at the start of combustion is provided, it is possible to prevent abnormal overheating at the start of combustion and perform stable refrigerant heating operation, and it is possible to improve the reliability and durability of the device. Further, since the compressor is operated according to the elapsed time, there is an advantage that the electricity cost of the compressor operation can be saved and the economical efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of a heat transfer device according to an embodiment of the present invention.

FIG. 2 is a refrigerant behavior control operation diagram of the embodiment of the present invention.

FIG. 3 is a system configuration diagram of a conventional heat transfer device.

[Explanation of symbols]

 1 Refrigerant Heater 2 Gas-Liquid Separator 4 Liquid Receiver 5 First Check Valve 7 First Open / Close Valve 9 Heat Transfer Section 10 Heating Circuit 12 Indoor Heat Exchanger 14 Second Check Valve 21 Cooling Circuit 22 Compressor 23 Outdoor Heat Exchanger 25 Second opening / closing valve 26 Flow path switching valve 37 Control device

Claims (3)

[Claims] 1. A refrigerant heater is connected to a gas-liquid separator, and the gas-liquid separator is connected to a first opening / closing valve on the inlet side and the outlet side,
A heating circuit in which the gas-liquid separator, the indoor heat exchanger, the second check valve, and the liquid receiver are sequentially pipe-connected to a heat transfer section that is respectively connected via a first check valve, and one end is a flow path switch. A cooling circuit having an outdoor heat exchanger and a compressor, the other end of which is additionally connected to the heating circuit via a second opening / closing valve, and combustion starts in accordance with the elapsed time from the stop of heating to the start of the next heating. A heat transfer device provided with a control device for changing the behavior of the refrigerant at the time. 2. The control means for changing the behavior of the refrigerant uses the first control by opening / closing the first opening / closing valve, the opening of the second opening / closing valve, and the gas purge start by the operation of the compressor as the opening / closing operation of the first opening / closing valve. A second control is added, and a third control is performed in which the opening / closing of the second opening / closing valve and the gas purge start by the operation of the compressor are added to the opening / closing operation of the first opening / closing valve following the pump down by the operation of the compressor. The heat transfer device according to claim 1, wherein the first to third controls are selected as the time becomes longer. 3. The heat transfer device according to claim 1, wherein the elapsed time from the heating stop to the heating start is from the combustion stop to the combustion start.