JPH05157263A - Heat transferring apparatus - Google Patents

Abstract

PURPOSE:To prevent an abnormal overheat of a refrigerant heater when a refrigerant amount in an apparatus is reduced due to leakage, etc., and to continue a stable heating operation in a heat transferring apparatus in which heat is utilized for room heating by using a pressure rise at the time of heating refrigerant. CONSTITUTION:The heat transferring apparatus comprises a heat transfer unit 18 in which a refrigerant heater 2 having a burner 16 and an air/liquid separator 1 are connected to an annular conduit and a reservoir 5 is connected to the conduit through a drop-in tube 7 having a first check valve 6 and a pressure equalizing tube 9 having a switching valve 8. Further, the apparatus comprises a circulation passage 19 in which the separator 1, a radiator 10, a second check valve 12 and the reservoir 5 are sequentially piped to be connected, a wall temperature sensor 22 provided at the heater 2, and a controller 23 for reducing a combustion amount of a burner 16 when a sensed temperature of the sensor 22 reaches a predetermined value.

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

That is, the gas-liquid separator 1 is arranged above the refrigerant heater 2 and is 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 line. ing. Further, the liquid receiver 5 is arranged 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 provided with a pressure equalizing pipe 9 having an opening / closing valve 8 by an outlet pipe. It is connected to the gas-liquid separator 1 via 4. The gas-liquid separator 1 and the radiator 10 arranged on the indoor side as the use side are connected by a gas refrigerant forward pipe 11, and the radiator 10 and the liquid receiver 5 are liquid refrigerant return pipes having a second check valve 12. It is connected at 13. 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 sequentially connected by piping. Reference numeral 14 is an evaporation temperature detector provided in the outlet pipe 4 of the refrigerant heater 2, and 15 is a control device for controlling the opening / closing time of the on-off valve 8 according to the temperature detected by the evaporation temperature detector 14. Reference numeral 16 is a burner provided in the refrigerant heater 2, and the burner 16 heats the refrigerant. 17 is a radiator 1
It is a blower installed in 0.

The operation of the above structure will be described below. In the refrigerant heater 2, the refrigerant heated by the combustion heat of the burner 16 flows into the gas-liquid separator 1 through the outlet pipe 4 in a two-phase state of gas and liquid, and the liquid refrigerant is heated again from the inlet pipe 3 by the refrigerant heating. Flows into the vessel 2. On the other hand, gas-liquid separator 1
The gas refrigerant of the two-phase state refrigerant that has flowed into the heat exchanger 10 enters the radiator 10 through the gas refrigerant forward pipe 11 and exchanges heat with the indoor air sent by the blower 17, condenses heat and condenses into supercooled liquid.

When the opening / closing valve 8 is closed, the supercooled liquid refrigerant condensed and liquefied in the radiator 10 is returned to the liquid refrigerant return pipe 13
Through the second check valve 12 to flow into the liquid receiver 5 by condensing the gas refrigerant. At this time, the pressure inside the liquid receiver 5 is lower than the pressure inside the gas-liquid separator 1, so the first check valve 6 is in a closed state. In this state,
When the open / close valve 8 is opened, the liquid receiver 5 and the gas-liquid separator 1 communicate with each other through the pressure equalizing pipe 9 to be in a pressure equalizing state, and the liquid refrigerant in the liquid receiver 5 passes through the first check valve 6 by gravity. It flows into the gas-liquid separator 1.

Next, when the opening / closing valve 8 is closed again, the first check valve 6 is closed, and the condensed subcooling liquid refrigerant of the radiator 10 is rapidly decompressed into the liquid receiver 5. The cycle in which the liquid receiver 5 is sucked by and the liquid receiver 5 is filled with the liquid refrigerant is repeated. As described above, the natural circulation cycle between the gas-liquid separator 1 and the refrigerant heater 2 is based on the evaporated refrigerant pressure, and the supply of the liquid refrigerant from the liquid receiver 5 to the gas-liquid separator 1 and the refrigerant heater 2 is performed by the open / close valve 8 It is an intermittent operation cycle according to the open / close cycle.

[0007]

In the above-mentioned conventional configuration, since the heat transfer is performed by heating the refrigerant, the opening / closing cycle of the opening / closing valve 8 is determined by the evaporation temperature of the refrigerant detected by the evaporation temperature detector 14 and the amount of combustion in the burner 16. It is controlled accordingly. Figure 4 shows the operating conditions in the opening and closing cycle closing time T _OFF and the open time was T _ON steady combustion time of the on-off valve _{8 T S (T S = T} OFF + T ON), from the open state at time t ₀ After switching to the closed state and accompanied by the depressurization start delay time T ₁ , the inside of the receiver 5 is cooled and condensed by the supercooled liquid refrigerant, and the inflow of the liquid refrigerant by depressurization is completed at the depressurization time _Tr (T _OFF = T
_l + T _r ). The liquid refrigerant which has finished flowing into the liquid receiver 5 is dropped to the refrigerant heater 2 side at the next opening time T _ON of the opening / closing valve 8 and the heat transfer is continued by repeating the opening / closing.

However, if the refrigerant enclosed in the heat transfer device is reduced due to leakage to the outside due to the passage of time or the like, the degree of supercooling of the liquid refrigerant during the heat transfer operation is reduced, and the depressurized amount in the receiver 5 is reduced. As a result, the inflow time of the liquid refrigerant into the liquid receiver 5 becomes longer and the inflow is not completed within a predetermined closing time, resulting in insufficient inflow.

Due to insufficient inflow of the liquid refrigerant into the liquid receiver 5, the supply of the liquid refrigerant to the refrigerant heater 2 becomes insufficient with respect to the combustion amount of the burner 16 and abnormal overheating occurs to stop the equipment. There was a problem with stable heating.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to prevent abnormal overheating during the refrigerant heating heat transfer operation, and to provide continuous stable heating operation.

[0011]

In order to achieve the above object, the present invention connects a refrigerant heater having a burner and a gas-liquid separator, and the gas-liquid separator and an inlet side and an outlet side are provided with an on-off valve and a first reverse valve. A heat transfer unit having a liquid receiver connected via a stop valve, an annular circulation path in which the gas-liquid separator, the radiator, the second check valve, and the liquid receiver are sequentially connected by piping, and the refrigerant heating A wall temperature detector provided in the furnace and a control device that lowers the upper limit value of the combustion amount of the burner when the detected temperature of the wall temperature detector reaches a predetermined value.

[0012]

According to the present invention, the wall temperature detector detects the insufficient supply of the liquid refrigerant to the refrigerant heater and reduces the combustion amount in the burner to make the refrigerant heating amount commensurate with the liquid refrigerant supply amount. By doing so, the occurrence of abnormal overheating can be prevented.

[0013]

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

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

Reference numeral 18 connects the refrigerant heater 2 and the gas-liquid separator 1 provided opposite to the burner 16 to the annular pipe line, and the liquid receiver 5 provided above the gas-liquid separator 1 is connected to the first check valve. It is a heat transfer section having a drop pipe 7 having 6 and an on-off valve 8 and being connected to the annular pipe line by a pressure equalizing pipe 9. Reference numeral 19 is an annular circulation path in which the gas-liquid separator 1, the radiator 10 having the blower 17, the second check valve 12, and the liquid receiver 5 are sequentially connected by piping. Reference numeral 20 denotes a room temperature detector provided in the radiator 10, and detects the temperature of the air flowing into the radiator 10. Reference numeral 21 is a fuel supply device that changes the amount of fuel supplied to the burner 16.

Reference numeral 22 is a wall temperature detector provided on the outer wall surface of the refrigerant heater 2 so as to be thermally joined thereto. 23 is electrically connected to the on-off valve 8, the evaporation temperature detector 14, the blower 17, the room temperature detector 20, the fuel supply device 21, and the wall temperature detector 22, and the temperature detected by the wall temperature detector 22 reaches a predetermined value. When reaching, the control device lowers the upper limit of the combustion amount of the burner 16 by the fuel supply device 21.

In the above structure, the heating operation for heat transfer by heating the refrigerant is performed by the opening / closing operation of the opening / closing valve 8, the combustion in the burner 16 and the operation of the blower 17, and the operation when the wall temperature of the refrigerant heater 2 rises will be described. It will be explained in 2.

In FIG. 2, time t₁At the beginning of combustion
Combustion amount upper limit value Q_L1The amount of combustion increases toward
The evaporation temperature detected by the evaporation temperature detector 14 (broken line in the figure
, And the wall temperature detector 22 detects the refrigerant heater wall
The temperature (indicated by the solid line in the figure) rises. Time t₂The initial burn
Burning amount upper limit Q_L1And the amount of combustion becomes constant. Meanwhile, outside
If the amount of refrigerant in the device has decreased due to a leak to the
Insufficient supply of liquid refrigerant to the refrigerant heater 2 over time
The temperature of the refrigerant heater rises significantly above the evaporation temperature due to the actualization.
A predetermined value T set as the coolant shortage detection temperature_H(This
Predetermined value of T_HIs set lower than the abnormal overheat detection temperature)
At time t₃When the control device 23 reaches the
Q of the combustion amount upper limit of the burner 16_L2Low to
Let me down. The combustion upper limit is Q_L2Cold by dropping to
Although the medium heater wall temperature and the evaporation temperature tend to decrease,
Upper limit of combustion amount Q after change_L2However, cooling against the liquid refrigerant supply amount
If the medium heating amount is large, the refrigerant heater wall temperature rises again.
Same time t_FourAgain the predetermined value T _HBy reaching and detecting
The upper limit of combustion amount is Q_L3Further down to. Q is the amount of combustion _L3
The amount of liquid refrigerant supplied to the
The heating amount is balanced and the wall temperature of the refrigerant heater decreases
The difference from the degree becomes small and stable heating is continued.

When the supply amount of the liquid refrigerant is insufficient, the wall temperature of the refrigerant heater rises significantly with respect to the evaporation temperature because the liquid component of the refrigerant that has exited the refrigerant heater 2 in the gas-liquid two-phase state. This is because the heat transfer coefficient of the flowing refrigerant decreases as the liquid refrigerant supply becomes insufficient and flows as the gas phase (gas) component increases, and the refrigerant heater wall temperature rise tends to occur at the refrigerant outlet side.

As described above, the rise in the temperature of the wall of the refrigerant heater is detected and the upper limit of the combustion amount is lowered, so that abnormal overheating is prevented in advance, and thermal decomposition of the refrigerant or thermal deterioration of the refrigerant heater is prevented. The reliability and durability of the transfer device can be improved.

Further, since the equipment is not stopped due to abnormal overheating and the heating capacity is reduced, the heating can be performed, so that the basic function as a heater is satisfied and the convenience is improved.

Not only when the amount of refrigerant in the apparatus decreases,
Even if the combustion amount becomes excessive due to variations in the setting of the combustion amount, it is effective in preventing abnormal overheating by setting the combustion amount to an appropriate value, and heating comfort is improved because heating can be continued.

[0023]

As described above, the heat transfer device of the present invention includes a heat transfer part having a burner, a refrigerant heater, a gas-liquid separator, a liquid receiver, a first check valve and an opening / closing valve, and the gas-liquid separator. ,
A radiator, a second check valve, an annular circulation path in which the liquid receiver is sequentially pipe-connected, and a wall temperature detector provided in the refrigerant heater,
When the detected temperature of the wall temperature detector reaches a predetermined value, since the control device is provided to lower the combustion amount upper limit value of the burner, even if the amount of refrigerant in the device is reduced due to leakage or the like, abnormal overheating occurs. This is effective in preventing the occurrence of heat and improving the reliability and durability of the heat transfer device.

Further, although the heating capacity is reduced, the heating function can be maintained, so that the convenience is improved, and further, the heating comfort is improved because the combustion amount is reduced to an appropriate value even if the combustion amount becomes excessively large. There is also an advantage of doing.

[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 control operation diagram of the embodiment of the present invention.

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

FIG. 4 is an opening / closing valve operation diagram in a conventional heat transfer device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas-liquid separator 2 Refrigerant heater 5 Liquid receiver 6 1st check valve 8 Open / close valve 10 Radiator 12 2nd check valve 16 Burner 18 Heat transfer part 19 Circulation path 22 Wall temperature detector 23 Control device

Claims (1)

[Claims] 1. A heat having a liquid receiver in which a refrigerant heater having a burner is connected to a gas-liquid separator, and the gas-liquid separator is connected to an inlet side and an outlet side through an on-off valve and a first check valve, respectively. A transport section, an annular circulation path in which the gas-liquid separator, the radiator, the second check valve, and the liquid receiver are sequentially pipe-connected,
A heat transfer device provided with a wall temperature detector provided in the refrigerant heater, and a control device that lowers a combustion amount upper limit value of the burner when a detected temperature of the wall temperature detector reaches a predetermined value.