JPH0718604B2 - Air conditioner - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an air conditioner that air-conditions by connecting indoor and outdoor units with heat medium pipes, and particularly heats a heat medium with a burner using a liquid fuel such as petroleum as a heat source. However, the present invention relates to an air conditioner that conveys heat to an indoor unit to perform heating.

2. Description of the Related Art A heat pump air conditioner is generally put into practical use as an air conditioner that performs heating and cooling by connecting indoor and outdoor units with a heat medium pipe. However, in the case of heat pump air conditioners, the capacity decreases at the low outdoor temperature when heating is the most necessary, and heating is temporarily stopped to defrost the outdoor heat exchanger, and defrosting operation is required. However, there are problems in heating operation. In order to solve the above problems of heating a heat pump air conditioner, a device has been proposed in which a heat medium is heated by a gas or oil burner, and heat is transferred to an indoor unit by a compressor for heating. In this case, electricity accompanying the operation of the compressor will be used together with gas or oil, and it has not come into widespread use in terms of operation and maintenance costs.

An air conditioner as shown in FIG. 7 has already been proposed as a solution to such a problem. In FIG. 7, during heating operation, first, when heating is started, the first solenoid valve 1, the second solenoid valve 2, the third solenoid valve 3, and the on-off valve 5 are closed, and the fourth solenoid valve is closed.
The solenoid valve 4 is opened and a burner (not shown) is ignited to start heating operation. The heat medium in the heat medium heater 6 is heated by the burner to evaporate, and the high temperature and high pressure heat medium gas evaporated by the increase of the evaporation pressure is transferred from the heat medium heater 6 through the fourth solenoid valve 4 and the heat medium pipe 7. Indoor heat exchanger 9
Pumped to. At this time, when the indoor fan 10 is operated, the heat medium gas of high temperature and high pressure radiates heat and is heated to condense and liquefy. The heat medium is from the heat medium pipe 8 to the first check valve.
After passing through 11, it flows into the liquid receiver 14 and receives the liquid. When the liquid level in the liquid receiver 14 reaches a certain level, the on-off valve 5 is opened, and the evaporating pressure is applied to the liquid receiver 14 and the same static pressure as that of the heat medium heater 6 is reached. The heat medium liquid in the liquid receiver 14 flows into the heat medium heater 6 due to the liquid head differential pressure. After the liquid level of the liquid receiver 14 is lowered, the on-off valve 5 is closed to be in the initial state.

At the end of the heating operation, the third solenoid valve 3 is opened, the opening / closing valve 5 is opened, and the compressor 16 is operated. Since the heat medium passage is sealed by the first solenoid valve 1 and the second check valve 12, it is distributed to the outdoor heat medium condenser 15, the accumulator 17, and various heat medium pipes connecting them. The heat medium that has been used is sucked and recovered by the operation of the compressor 16, and all the heat medium is pumped to the heat medium heater 6 through the third check valve 13. After completion of this recovery operation, the compressor 16 is stopped, and the first solenoid valve 1, the second solenoid valve 2, the third solenoid valve 3, the fourth solenoid valve 4, the open / close valve 5
Closed and returns to the heating stopped state.

As described above, during the heating operation, the heating cycle is configured by sending the heat medium liquid by using the increase in the vapor pressure due to the heating of the heat medium, and the conventional operation of the compressor or pump using electricity as in the past. The heating operation can be performed without the need for.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the air conditioner as described above, the heat medium pumped up to the heat medium heater 6 at the end of the heating operation causes the compressor 16, the accumulator 17, and the outdoor heat medium condensing during the heating operation stop. Since it gradually leaks to the heating device 15, the amount of heat medium in the heating system path decreases, and when heating operation is performed while the amount of heat medium is insufficient, the temperature of the heat medium heater 6 rises abnormally. It had the problem of causing danger.

The present invention solves the above problems, and an object of the present invention is to provide an air conditioner that can secure the amount of heat medium in the heating system path during heating operation.

Means for Solving the Problems In order to solve the above problems, the air conditioner of the present invention is a heater that heats a heat medium by combustion of liquid fuel, a vaporizer that vaporizes liquid fuel, and the vaporizer is heated. A vaporizing heater, temperature detecting means for detecting the temperature in the vaporizer, a heat exchanger for heating air by heat exchange with a heat medium, and heating by circulating the heat medium between the heater and the exchanger. A heat transfer means for performing, and a recovery means for recovering the heat medium in the heater,
The vaporization heater, the heat transfer unit, and a control unit for controlling the recovery unit, and the control unit, a heating operation unit for driving the heat transfer unit, a recovery operation unit for driving the recovery unit, A vaporization heater control unit that controls energization of the vaporization heater according to the temperature detected by the temperature detection unit, and the operation time of the recovery operation unit from the time when the operation switch is turned on, and the first heating operation permission signal when a predetermined time has elapsed. , A comparator for outputting a second heating operation permission signal when the temperature detected by the temperature detecting means exceeds a set temperature, and a comparator for outputting the first and second heating operation permission signals. The heating operation unit is instructed to operate, and the recovery operation unit is instructed to stop operation.

The present invention has the above-described configuration, and before the heating operation unit starts the heating operation, the temperature inside the carburetor detected by the temperature detection means exceeds the predetermined temperature to reach the vaporizable temperature of the liquid fuel, and the timer is set. The collection operation unit continues the collection operation of the heat medium until the measurement of the predetermined time is completed. Therefore, when the heating operation is performed, the amount of heat medium in the heating system path is not insufficient, and the temperature of the heat medium heater does not rise abnormally.

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings. In the embodiments, the same parts as those in FIG. 7 are designated by the same reference numerals for convenience, detailed description will be omitted, and different parts will be mainly described.

FIG. 2 is a system configuration diagram of an air conditioner showing an embodiment of the present invention. The vaporizer 18 is connected to the heater 6 that heats the heat medium by burning the liquid fuel, and vaporizes the liquid fuel.
The vaporization heater 19 is disposed at the bottom of the vaporizer 18 and
To heat. The vaporizer 18 is provided with temperature detecting means 20 for detecting the temperature of the vaporizer 18. Heat exchanger 9
Heats the air by heat exchange with the heat medium. Heater 6
The heat transfer means 21 having a unit circulates a heat medium to perform heating.
The recovery means 22 includes a compressor 16, an accumulator 17, etc., and recovers the heat medium to the heater 6. The vaporization heater 19, the heat transfer means 21, and the recovery means 22 are controlled by the control unit 23.

FIG. 1 shows a block diagram of the control unit 23. Run switch 24
Is connected to the timer 28, the switching unit 30, and the vaporization heater control unit 27 to switch the operating state. The heating operation unit 25 is a heat transfer means.
21 is driven, and the recovery operation unit 26 drives the recovery means 22. The vaporization heater control unit 27 controls energization of the vaporization heater 19. The timer 28 connected to the operation switch 24
The operation time of the recovery operation unit 26 is measured from the time point 24 is turned on, and the first heating operation permission signal is output when a predetermined time has elapsed.
The comparison unit 29 is connected to the temperature detection unit 20 and the switching unit 30, and outputs a second heating operation permission signal to the switching unit 30 when the temperature detected by the temperature detection unit 20 exceeds the set temperature. The switching unit 30 for switching between the heating operation and the collecting operation inputs the signals from the operation switch 24, the timer 28, and the comparison unit 29, and when the first and second heating operation permission signals are input. First, the heating operation unit 25 is instructed to operate, and the recovery operation unit 26 is instructed to stop operation.

The control of the vaporization heater 19 will be described with reference to FIGS. 3, 5, and 6. T is the temperature detected by the temperature detecting means 20 of the vaporizer 18. T _ON and T _OFF are input temperatures and cut temperatures that change the energization state of the vaporization heater 19 from off to on and from on to off, and the cut temperature T _OFF is higher than the input temperature T _ON . When the operation switch 24 is off, the vaporization heater 19 is not energized. When the operation switch 24 is switched from off to on, energization to the vaporization heater 19 is started, and energization is maintained until the detected temperature T exceeds the off temperature T _OFF . When the detected temperature T exceeds the cutoff temperature T _OFF , the power supply to the vaporization heater 19 is stopped, and when the detected temperature T falls below the input temperature T _ON , the vaporization heater 1
Energization to 9 is resumed.

The control of the heating operation unit 25 and the recovery operation unit 26 will be described based on FIGS. 4, 5, and 6. T _S is the set temperature set by the user, which is higher than the input temperature T _ON and the cut temperature T
Lower than _OFF . When the user switches the operation switch 24 from OFF to ON during the heating start time, the recovery operation unit 26 starts driving the recovery means 22. When the recovery operation is started, the timer 28 starts and counts a predetermined time. After the recovery operation is started, when the timer 28 finishes counting the predetermined time, the first heating operation permission signal is output to the switching unit 30, and when the detected temperature T of the temperature detection means 20 exceeds the set temperature T _S , the comparison unit The second heating operation permission signal is output from 29.
The collection operation is continued until both heating operation permission signals are input to the switching unit 30. That is, the collection operation is continued until the following conditions (1) and (2) are satisfied.

(1) The detected temperature T of the temperature detecting means 20 exceeds the set temperature T _S.

(2) The timer 28 finishes counting the predetermined time.

When the above conditions (1) and (2) are satisfied, the switching unit 30 switches the operation instruction from the collection operation unit 26 to the heating operation unit 25.
The recovery operation ends, and the heating operation starts.

Effects of the Invention As described above, according to the air conditioner of the present invention, the following effects are obtained.

(1) When the heating operation is started, the heat medium recovery operation is performed until the temperature of the carburetor exceeds a predetermined temperature and reaches the vaporizable temperature. Therefore, while the heating operation is stopped, the heat medium condenser and the outdoor heat medium condenser are It is possible to recover the heat medium that has gradually leaked to the accumulator or compressor, prevent the shortage of the heat medium in the heating system path, prevent the temperature of the heat medium heater from rising abnormally, and operate it. The waiting time from when the switch is turned on to when the heating operation is actually started can be effectively used.

(2) At the start of heating operation, the temperature of the carburetor is relatively high,
Even when the time to reach the vaporizable temperature is short, the recovery operation is performed until the minimum timer finishes measuring the predetermined time, so that the amount of heat medium that can be recovered can be guaranteed during this period.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control unit configuration of an air conditioner in one embodiment of the present invention, FIG. 2 is a circuit configuration diagram of the air conditioner, and FIG. 3 is a control of a vaporization heater of the air conditioner. 4 is a flowchart for explaining the operating states of the heating operation section and the recovery operation section of the air conditioner,
FIG. 5 and FIG. 6 are graphs and time charts showing the operating states of the vaporization heater and the air conditioner depending on the temperature detected by the temperature detecting means of the air conditioner, the state of the timer and the operation switch, respectively, and FIG. It is a circuit block diagram of the air conditioner. 6 ... Heater, 9 ... Indoor heat exchanger, 14 ... Liquid receiver, 16 ... Compressor, 18 ... Vaporizer, 19 ... Vaporizing heater, 20 ... Temperature detecting means,
21 ... Heat transfer means, 22 ... Recovery means, 23 ... Control section, 25 ... Heating operation section, 26 ... Recovery operation section, 27 ... Vaporization heater control section, 28 ...
Timer, 29 ... Comparison section, 30 ... Switching section.

Claims (1)

[Claims] 1. A heater for heating a heat medium by burning a liquid fuel, a vaporizer for vaporizing the liquid fuel, a vaporization heater for heating the vaporizer, and a temperature detecting means for detecting a temperature in the vaporizer. A heat exchanger that heats air by heat exchange with a heat medium; heat transfer means that circulates the heat medium in the heater and the heat exchanger to perform heating; and recovers the heat medium in the heater. A recovery unit, a controller that controls the vaporization heater, the heat transfer unit, and the recovery unit are provided, and the control unit includes a heating operation unit that drives the heat transfer unit and a recovery unit that drives the recovery unit. An operation unit, a vaporization heater control unit that controls energization of the vaporization heater according to the temperature detected by the temperature detection unit, and an operation time of the recovery operation unit from the time when the operation switch is turned on. Output heating operation permission signal Timer, a comparing unit that outputs a second heating operation permission signal when the temperature detected by the temperature detection means exceeds a set temperature, and the heating operation when the first and second heating operation permission signals are input. An air conditioner having a switching section for instructing a section to operate and a recovery operation section for stopping the operation.