JP3139099B2 - Heat transfer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, as a heat transfer apparatus for heating by this type of refrigerant heating, for example, Japanese Patent Application Laid-Open No. 57-101263.
There is a configuration as shown in FIG.

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

[0004] In the heating operation, after the pump 41 drives the compressor 41 to transfer the refrigerant from the outdoor heat exchanger 44 to the refrigerant heater 55, the refrigerant heater 55 is heated by the burner 54 to form an evaporator. The heating cycle is constituted by using the indoor heat exchanger 48 as a condenser and the refrigerant pump 53 as a refrigerant conveying means, and the cooling is constituted by a conventional cooling cycle driven by a compressor.

[0005] As another conventional heat transfer apparatus for heating by heating a refrigerant, cooling is performed by a conventional method driven by a compressor, and heating is performed by using the compressor for cooling as a refrigerant gas pump (not shown). There is.

[0006]

However, in the above-mentioned conventional configuration, a refrigerant pump or a compressor must be driven as a means for circulating the refrigerant during the heating operation, and a relatively large electric input is used as the heat transfer power. (When heating capacity is about 4000 kcal / h, 50-60
W, about 300-400 W by the compressor), and the heating running cost is increased.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. Heating power during heating is extremely small, and heating operation is performed by heating the refrigerant stably with respect to 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 a first open / close valve and a first check valve to an inlet and an outlet of a receiver. A heating circuit in which the gas-liquid separator, the indoor heat exchanger, the second check valve, and the liquid receiver are sequentially connected to a heat transfer unit connected to the gas-liquid separator via A cooling circuit having an outdoor heat exchanger and a compressor additionally connected to the heating circuit via a second on-off valve via a valve, and combustion starting according to the elapsed time from the stop of heating to the start of the next heating. Equipped with a control device to change the refrigerant behavior at the time,
The control device includes a first control by opening and closing a first on-off valve, a second control in which a second on-off valve is opened and a gas purge is started by operating a compressor to an on-off operation of the first on-off valve, Following the pump down due to the operation described above, the third control in which the opening and closing of the second opening and closing valve and the activation of the gas purge by the operation of the compressor are added to the opening and closing operation of the first opening and closing valve. 3 is selected.

[0009]

According to the present invention, the above construction reduces the running cost by repeating the opening / closing operation of the first opening / closing valve, which requires very little electric input, to reduce the running cost. The amount of refrigerant leaking into the cooling circuit, which increases with time, and the distribution of liquid refrigerant in the heating circuit, which changes over time, are optimally changed to control the behavior of the refrigerant. In this case, the gas refrigerant in the refrigerant heater is discharged to the cooling circuit side to secure the liquid refrigerant in the refrigerant heater and to reduce the number of pump-downs that require a long operation time of the compressor.

[0010] By securing the liquid refrigerant in the refrigerant heater, abnormal overheating in the refrigerant heater at the start of combustion can be prevented, and the heating operation can be performed by stable refrigerant heating. Electricity input can be reduced and running cost can be reduced.

[0011]

FIG. 1 shows an embodiment of the present invention.

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

Reference numeral 21 denotes a cooling circuit having a compressor 22, an outdoor heat exchanger 23, a first pressure reducing device 24, and a second on-off valve 25. One end is connected to the gas refrigerant pipe 13 via a flow path switching valve 26. At the same time, a 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 a flow path switching valve 26 formed 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 denotes a second cooling circuit which connects the inlet pipe 3 and the liquid refrigerant pipe 15 and has a third on-off 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; a liquid-side and gas-side service valve 32, 33 and a liquid-side and gas-side joint 34;
Between 35, the length of the connecting refrigerant pipe according to the installation distance between the outdoor side and the indoor side can be arbitrarily set.

Reference numeral 36 denotes an outdoor blower provided in the outdoor heat exchanger 23. Reference numeral 37 denotes an overheat detector 1a, a first on-off 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 behavior of the refrigerant 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 configuration, 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 refrigerant separated into gas and liquid 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 and further becomes a supercooled liquid. When the first opening / closing valve 7 of the pressure equalizing pipe 8 communicating with the 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 receiver 4, the saturated gas refrigerant in the receiver 4 is cooled and condensed by the supercooled liquid. It flows at a stretch until the inside of the vessel 4 is full. Next, when the first opening / closing valve 7 is opened by the control device 37, the pressure between the liquid receiver 4 and the gas-liquid separator 2 is communicated by the equalizing pipe 8 to have the same pressure, and the liquid refrigerant in the liquid receiver 4 is vaporized by gravity. The refrigerant drops to 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 required for the circulation of the refrigerant is only the power consumption of the electromagnetic valve, and the opening / closing operation of the electromagnetic valve having a rated input of about 7W substantially reduces the power to about 3 to 4 Wh. Refrigerant can be circulated with very small power.

FIG. 2 shows that the room temperature detector 20 detects that the room temperature detector 20 has fallen below the set value from the thermo-OFF 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. This shows a change in refrigerant behavior control due to a longer elapsed time from the start of combustion of the burner 17 to the start of the thermo-ON at which heating starts.

In FIG. 2, at time t ₁ , the combustion is stopped by the thermo OFF, the heating is stopped, and the short elapsed time Δt
The first control of the opening and closing operation of the first on-off valve 7 at the time t ₂ for ₁ after thermo-ON the heating start by the start of combustion. Then become Heating stopped by thermo OFF at time t _3, a long elapsed time _{Δt 2 (Δt 2> Δt 1} ) When the heating starts after thermo ON of the second on-off valve before the combustion start time t ₄ 25 Short opening time (about 10 seconds) and compressor 2
The gas refrigerant in the refrigerant heater 1 is caused to flow out to the outdoor heat exchanger 23 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, a gas purge is started to draw the liquid refrigerant into the refrigerant heater 1 and collect the refrigerant leaking slightly to the outdoor heat exchanger 23 into the heating circuit.

Further, time t_FiveHeated by thermo OFF
Stop and very long elapsed time Δt_Three(Δt_Three> Δt
_Two> Δt₁), When heating starts with thermo ON,
Interval t ₆Before the start of combustion by the operation of the compressor 22
Refrigerant leaked to outdoor heat exchanger 23 side when down (about 3 minutes)
In the heating circuit, and then the second on-off valve 25
Opening (about 10 seconds) and continuing compressor operation (about 30 seconds)
Of the above-described gas purge by the opening / closing operation of the first opening / closing valve 7
In addition.

As described above, the behavior of the refrigerant is changed according to the elapsed time from the stop of combustion to the start of combustion. First, the pressure difference between the cooling circuit and the cooling circuit which is at rest due to the decrease in pressure of the heating circuit due to the stop of combustion is reduced. The second on-off valve 25, the fourth
This is because the amount of refrigerant leakage at the valve section that separates the heating circuit and the cooling circuit, such as the check valve 28 and the flow path switching valve 26, increases. This is particularly noticeable when a four-way valve is used as the flow path switching valve 26. Become.

Secondly, in addition to stopping the combustion, the evaporating pressure of the refrigerant decreases and the degree of supercooling of the liquid refrigerant decreases, so that the circulation operation of the liquid refrigerant due to the opening / closing operation of the first on-off valve 7 weakens and stops. This is because the liquid refrigerant in the refrigerant heater 1 evaporates and decreases due to residual heat of the refrigerant heater 1 and evaporates over time.

In response to the natural behavior of the refrigerant at the time of stopping the combustion, the behavior of the refrigerant at the start of the combustion is changed with the lapse of time. Since it is distributed in the compressor 1, the operation of only the first opening / closing valve 7 without operating the compressor 22 is sufficient, and in the next long elapsed time Δt2, the leakage of the refrigerant to the cooling circuit 21 is still small but the remaining amount is small. Since the liquid refrigerant in the refrigerant heater 1 is reduced by heat, it is only necessary to start the gas purge for forcibly drawing the liquid refrigerant into the refrigerant heater 1 by extracting a small amount of gas refrigerant from the refrigerant heater 1. The operation time of No. 22 is short. Furthermore, in the very long elapsed time t3, the refrigerant often leaks into the cooling circuit 21 and the distribution of the liquid refrigerant is uncertain, so that the refrigerant is recovered to the heating circuit 10 by pumping down the compressor 22 and recovered. After distributing the refrigerant so that the liquid refrigerant pipe 15 side is filled with liquid, the liquid refrigerant is drawn into the refrigerant heater 1 by gas purge activation.

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

Furthermore, the number of pump-down operations requiring a long operation time of the compressor at the start of combustion can be reduced,
The operation time of the compressor that consumes a large amount of electricity is minimized, the running cost is reduced, and the economy is improved.

Also, when heating is turned on by a switch after a lapse of time after the heating is turned off by an external switch such as a remote controller (not shown), it is needless to say that the same can be considered as the thermo-on after the thermo-off. No.

Furthermore, since the remote control may be turned off while the thermostat is off, the elapsed time from the stop of the heating to the start of the heating is more practical and appropriate to be the elapsed time from the stop of the combustion to the start of the combustion. 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 on-off valve 25 and the third on-off valve 30 are opened, the compressor 22, the indoor blower 11 and the outdoor blower 36 are opened.
By the operation described above, the conventional compressor-driven cooling is performed.

[0027]

As described above, the heat transfer apparatus according to the present invention includes an indoor heat exchanger in a heat transfer section having a refrigerant heater, a gas-liquid separator, a liquid receiver, a first check valve, and a first on-off valve. A heating circuit connected thereto, a cooling circuit having an outdoor heat exchanger and a compressor additionally connected at one end to the heating circuit via a flow path switching valve and the other end via a second on-off valve; and First control of only operation of the first on-off valve according to the elapsed time until the start of heating,
A second control with a gas purge start, a third control with a pump down and a gas purge start, and a control device for changing the behavior of the refrigerant at the start of combustion are provided. Combustion can be started with the liquid refrigerant in the refrigerant heater regardless of the time, preventing abnormal overheating at the start of combustion, enabling stable refrigerant heating operation, and improving the reliability and durability of equipment. There is. In addition, the number of times of the pump-down operation, which requires a long operation time of the compressor at the start of heating, can be reduced. The effect is that the performance can be improved.

[Brief description of the 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 according to an embodiment of the present invention.

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

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 refrigerant heater 2 gas-liquid separator 4 liquid receiver 5 first check valve 7 first on-off 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 on-off valve 26 Flow path switching valve 37 Controller

Continuation of the front page (56) References JP-A-1-305238 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24D 7/00

Claims (1)

(57) [Claims] 1. A refrigerant heater and a gas-liquid separator are connected,
A first on-off valve and a first reverse valve are connected to the inlet side and the outlet side of the receiver.
Heat connected to the gas-liquid separator via a stop valve
A heating circuit in which the gas-liquid separator, the indoor heat exchanger, the second check valve, and the liquid receiver are sequentially connected to the transfer section , one end is provided via a flow path switching valve, and the other end is provided via a second opening / closing valve. A cooling circuit having an outdoor heat exchanger and a compressor additionally connected to the heating circuit, and a control device for changing 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.
The control device is configured to control the first on / off operation of the first on / off valve.
Control, the opening and closing of the second on-off valve and the operation of the compressor
A second control in which charging start is added to the opening / closing operation of the first opening / closing valve;
Following the pump down by the operation of the compressor, the second on-off valve
Opening and start of gas purge by compressor operation
The third control in addition to the opening and closing operation of
And a heat transfer device for selecting the first to third controls .