JP2806109B2 - 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 A conventional heat transfer device is disclosed in, for example,
As shown in Japanese Patent No. 51631, the configuration is as shown in FIG.

[0003] That is, the gas-liquid separator 1 is disposed above the refrigerant heater 2 and connected by an inlet pipe 3 of the refrigerant heater 2 and an outlet pipe 4 of the refrigerant heater 2 and connected by an annular pipe. ing. The liquid receiver 5 is disposed above the gas-liquid separator 1, is connected to the gas-liquid separator 1 by a drop pipe 7 having a first check valve 6, and is further connected to an outlet pipe by a pressure equalizing pipe 9 having an on-off valve 8. 4 is connected to the gas-liquid separator 1. The gas-liquid separator 1 and a radiator 10 arranged on the indoor side as a utilization side are connected by a gas refrigerant outflow pipe 11, and the radiator 10 and the liquid receiver 5 are connected to a liquid refrigerant return pipe having a second check valve 12. 13 are connected. As described above, the gas-liquid separator 1, the radiator 10, the second check valve 12, the liquid receiver 5, and the first check valve 6 form an annular circulation path that is sequentially connected to the pipe. Reference numeral 14 denotes a temperature detector provided in the outlet pipe 4 of the refrigerant heater 2, and reference numeral 15 denotes a control device that controls the opening / closing time of the on-off valve 8 based on the temperature detected by the temperature detector 14. Reference numeral 16 denotes a burner provided in the refrigerant heater 2, and the refrigerant is heated by the burner 16. 17 is a blower provided in the radiator 10.

The operation of the above configuration will be described below. In the refrigerant heater 2, the refrigerant heated by the combustion heat of the burner 16 passes through the outlet pipe 4 in the two-phase state of gas and liquid, flows into the gas-liquid separator 1, and the liquid refrigerant heats again from the inlet pipe 3. Into the vessel 2. On the other hand, the gas-liquid separator 1
Of the two-phase refrigerant flowing into the gas refrigerant, the gas refrigerant enters the radiator 10 through the gas refrigerant outflow pipe 11, exchanges heat with the room air sent by the blower 17, radiates and condenses, and turns into supercooled liquid.

When the on-off valve 8 is closed, the supercooled liquid refrigerant condensed and liquefied by the radiator 10 is supplied to the liquid refrigerant return pipe 13.
Then, the gas refrigerant flows into the liquid receiver 5 through the second check valve 12 by condensing the gas refrigerant. At this time, since the pressure in the liquid receiver 5 is lower than the pressure in the gas-liquid separator 1, the first check valve 6 is in a closed state. In this state,
When the on-off valve 8 is opened, the liquid receiver 5 and the gas-liquid separator 1 communicate with each other by the pressure equalizing pipe 9 to be in a pressure equalized state, and the liquid refrigerant in the liquid receiver 5 passes through the first check valve 6 due to gravity. The gas flows into the gas-liquid separator 1.

Next, when the on-off valve 8 is closed again, the first check valve 6 is closed, and the condensed supercooled liquid refrigerant of the radiator 10 flows into the receiver 5 and the pressure in the receiver is rapidly reduced. , And the cycle in which the receiver 5 is filled with the liquid refrigerant is repeated. As described above, a natural circulation cycle is performed between the gas-liquid separator 1 and the refrigerant heater 2 by the evaporated refrigerant pressure, and the supply of the liquid refrigerant from the receiver 5 to the gas-liquid separator 1 and the refrigerant heater 2 is performed by the on-off valve 8. Is an intermittent operation cycle based on the opening / closing cycle.

[0007]

In the above-mentioned conventional construction, in order to carry out heat transfer by heating the refrigerant, the opening / closing cycle of the on-off valve 8 depends on the evaporation temperature of the refrigerant detected by the temperature detector 14 and the amount of combustion in the burner 16. Is properly controlled. Figure 4 shows the operating conditions of this between closing the steady combustion time of the on-off valve 8 T _OF and closing period T _S which is opened time _{T ON (T S = T OF} + T ON), from the open state at time t ₁ inflow of the liquid refrigerant by decompression in later receiver 5 entailed a vacuum start delay time T _l with switched to the closed state is cooled and condensed by the supercooled liquid refrigerant pressure reducing time T _r is completed (T _oF = T _l +
_Tr ). The liquid refrigerant that has flowed into the receiver 5 is supplied to the next on-off valve 8.
At the opening time T _ON of the above, the heat is transferred to the refrigerant heater 2 side, and the heat transfer is continued by repeating the opening and closing.

As described above, there is no problem in stably continuing the heat transfer during the steady combustion. But,
In the case where this heat transfer is used for heating, for example, when the temperature of the indoor side (room temperature) on the user side rises and reaches a set value, combustion stops (hereinafter referred to as thermo-OFF) and the room temperature falls below the set value. Start of combustion (hereinafter thermo ON)
), The behavior of the liquid refrigerant becomes unstable, the flow of the liquid refrigerant into the receiver 5 becomes uncertain, and abnormal overheating occurs in the refrigerant heater. There is a problem in the stable heating operation at the time of a transient change, such as causing the equipment to stop due to empty baking when it is severe.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a stable heating operation by improving the circulation of the refrigerant at the time of a transient change in the heat transfer by heating the refrigerant.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a liquid receiver having a refrigerant heater having a burner and a gas-liquid separator connected to an annular conduit, and provided above the gas-liquid separator. A heat transfer unit connected to the annular conduit with a dropping pipe having a first check valve and a pressure equalizing pipe having an on-off valve, the gas-liquid separator, a radiator having a blower, a second check valve, An annular circulation path in which liquid receivers are sequentially connected to a pipe, and when the combustion of the burner is stopped, the air volume of the blower is reduced to a predetermined value, at the start of combustion, the air volume is increased to a predetermined value, and the rate of change of the air volume is increased or decreased. Has a configuration in which a control device for increasing the amount of air flow reduction is provided.

[0011]

According to the present invention, the supercooling degree of the liquid refrigerant generated when the refrigerant pressure suddenly decreases by rapidly reducing the blower air volume of the radiator to slow down the refrigerant pressure when the combustion is stopped such as when the thermostat is turned off. To prevent the liquid refrigerant from flowing into the receiver due to the rapid decrease in the temperature. Furthermore, at the start of combustion such as thermo-ON, the blower air volume is gradually increased to rapidly increase the refrigerant pressure to increase the degree of supercooling of the liquid refrigerant, and the amount of refrigerant due to the rapid increase in the amount of liquid refrigerant retained in the radiator. Prevents imbalance in distribution and promotes the flow of liquid refrigerant into the receiver.

As described above, when the combustion is stopped and when the combustion is started, a state in which the liquid refrigerant easily flows into the liquid receiver is created, the refrigerant circulation is improved, and the occurrence of abnormal overheating in the refrigerant heater can be prevented.

[0013]

FIG. 1 shows an embodiment of the present invention.

In FIG. 1, the same reference numerals as those in FIG. 3 denote the same members, and have the same functions.
The different points will be mainly described.

A refrigerant heater 2 and a gas-liquid separator 1 provided opposite to the burner 16 are connected to an annular conduit, and a liquid receiver 5 provided above the gas-liquid separator 1 is connected to a first check valve. 6 is a heat transfer section connected to the annular pipe by a drop pipe 7 having an opening 6 and a pressure equalizing pipe 9 having an on-off valve 8. 19 is a gas-liquid separator 1, a radiator 10 having a blower 17, and a second check valve 1.
2. An annular circulation path in which the liquid receivers 5 are sequentially connected by piping.
Reference numeral 20 denotes a room temperature detector provided on the radiator 10, and the radiator 1
For 0, the temperature of the air flowing in is detected. Reference numeral 21 denotes a combustion amount varying device that varies the combustion amount of the burner 16.

Numeral 22 is electrically connected to the on-off valve 8, the temperature detector 14, the blower 17, the room temperature detector 20, and the variable combustion amount device 21, and is connected to the blower 1 when the burner 16 stops burning.
7 is a control device for reducing the air flow to a predetermined value, increasing the air flow to a predetermined value at the start of combustion, and increasing or decreasing the rate of increase or decrease of the air flow when the air flow is reduced.

In the above configuration, the heating operation of the heat transfer by the refrigerant heating is performed by the opening / closing operation of the on-off valve 8, the combustion of the burner 16, and the operation of the blower 17, but the thermo OFF / ON.
The operation at the time of stopping the combustion and starting the combustion will be described with reference to FIG.

[0018] Room temperature on the user side by heat transfer operation of refrigerant heating
Rises, and the room temperature detector 20 sets a predetermined value
When the control device 22 detects that the
Time t as F₀To stop the combustion. Open / close valve even after stopping combustion
8 is opening and closing operation. The blower 17 of the radiator 10 has V₁
Operating at the air volume of ₀
To rapidly reduce the air flow.

[0019] The air flow rate of decrease in this case to produce a flow rate change amount ΔV between the change time Delta] t ₀ are timer controlled.

[0020] Then the blower 17 together with the combustion initiated at the time t _S by thermo ON gradually increase the air volume to a predetermined value V _1.

Here, the timer is controlled so that the rate of increase of the air flow produces an air flow change amount ΔV during the change time Δt _S.

In addition, since the speed of change of the air flow is increased when the air flow is reduced, the change time is set to Δt ₀ <Δt _S.

As described above, the air flow rate of the blower is reduced when the combustion is stopped and increased when the combustion is started, and the rate of change of the air flow is reduced when the air flow is reduced and the speed is increased when the air flow is increased. Slowing down the evaporation pressure and slowing down the degree of supercooling of the liquid refrigerant, continuing the flow of the liquid refrigerant into the receiver due to the pressure reduction of the receiver when the on-off valve is closed, and leaving the remaining refrigerant heater Heat is recovered to the user side to prevent the occurrence of abnormal overheating, and at the start of combustion, the evaporation pressure of the refrigerant is quickly increased to increase the degree of supercooling of the liquid refrigerant and to the radiator that occurs when the heat radiation capacity is excessive. Prevents imbalance in refrigerant volume distribution due to temporary sudden increase in refrigerant, promotes inflow of liquid refrigerant into the receiver due to reduced pressure of the receiver, and improves refrigerant circulation,
Realizes stable start-up operation that prevents abnormal overheating.

As described above, the abnormal overheating of the refrigerant heater at the time of stopping the combustion and at the start of the combustion is prevented, thereby preventing the thermal decomposition of the refrigerant or the deterioration of the refrigerant heater from occurring. Durability can be improved.

Furthermore, since the residual heat can be recovered to the indoor side, which is the utilization side, at the time of stopping the combustion, waste of energy can be saved and the economic efficiency can be improved.

Further, if the air flow is reduced by using timer control, there is no response delay due to heat capacity or the like when the refrigerant temperature is detected and the air flow is controlled, and there is no response delay when the pressure is reduced relatively quickly. It is effective because it can follow, and is simple and practical.

[0027]

As described above, the heat transfer apparatus according to the present invention comprises a heat transfer section having a burner, a refrigerant heater, a gas-liquid separator, a liquid receiver, a first check valve, an on-off valve, a gas-liquid separator, A radiator having a blower, a second check valve, a circulation path in which a liquid receiver is sequentially connected, and when the burner stops burning, the air volume of the blower is reduced to a predetermined value, and when the combustion starts, the air volume is increased to a predetermined value. ,
In addition, a control device that increases the rate of change of the air flow to increase when the air flow is reduced is provided, so that abnormal overheating of the refrigerant heater at the time of combustion stop and start of combustion can be prevented, and the reliability and durability of the heat transfer device The effect is that the performance can be improved.
Further, there is also an advantage that the residual heat of the refrigerant heater can be recovered to the indoor side, which is the use side, when the combustion is stopped, and the economic efficiency is 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 control operation diagram according to the embodiment of the present invention.

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

FIG. 4 is an explanatory diagram of an on-off valve operation of a conventional heat transfer device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 gas-liquid separator 2 refrigerant heater 5 liquid receiver 6 first check valve 7 drop pipe 8 on-off valve 9 equalizing pipe 10 radiator 12 second check valve 16 burner 17 blower 18 heat transfer section 19 circulation path 22 control apparatus

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F24D 7/00

Claims (2)

(57) [Claims] A refrigerant heater having a burner and a gas-liquid separator are connected to an annular conduit, and a receiver provided above the gas-liquid separator is provided with a dropping pipe having a first check valve and an on-off valve. A heat transfer unit connected to the annular conduit with an equalizing pipe having
The gas-liquid separator, a radiator having a blower, a second check valve, an annular circulation path in which the liquid receiver is sequentially connected with a pipe, and reducing the air volume of the blower to a predetermined value when combustion of the burner is stopped, A heat transfer device provided with a control device for increasing the air volume to a predetermined value at the start of combustion and increasing or decreasing the air volume at a rate of increasing or decreasing the air volume. 2. The heat transfer device according to claim 1, wherein timer control is performed when the air volume is reduced.