JPH0336449A - Air conditioner - Google Patents

Abstract

PURPOSE:To provide a quick start-up of heating by a method wherein in the beginning of heating operation, the capacity of a compressor is immediately set at a value corresponding to the load, the heating rate of a refrigerant heater is gradually increased toward a value corresponding to the load, and then the capacity of the compressor and the heating rate of the refrigerant heater are respectively controlled corresponding to the load. CONSTITUTION:In heating operation, when start-up operation is carried out, a controller 20 immediately sets the operating frequency (output frequency of an inverter circuit 23) of a compressor 1 at a value corresponding the load, and outputs a heating capacity instruction value by which the heating capacity is increased one step for every certain time period based on a timer count. The valve lift of a proportional valve 11, that is, the heating rate of a refrigerant heater 9 (combustion rate of a gas burner 10) is set based on the heating capacity instruction value. Thus, with the compressor 1 set at an operating frequency corresponding to the load, the heating rate of the refrigerant heater 9 is gradually increased to increase the heating capacity. After that, when the heating capacity instruction value reaches the load of a room, the heating capacity instruction value is varied depending on the load of the room, and the valve lift of the proportional valve 11, that is, the heating rate of the refrigerant heater 9, is set corresponding to the heating capacity instruction value.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to an air conditioner equipped with a refrigerant heater.

(Prior art) An air conditioner is equipped with a heat pump refrigeration cycle having a variable capacity compressor and a refrigerant heater, and utilizes the refrigerant heating action of the refrigerant heater and the heat pumping action of the heat pump refrigeration cycle. There are some that perform heating operation.

The heating operation control of such an air conditioner is shown in FIGS. 4 and 5.

That is, when the operation start operation is performed, the heating capacity command value i is outputted, which increases by one step at predetermined time intervals based on the timer count. When this heating capacity command value l is output, the operating frequency ft of the compressor and the heating jl of the refrigerant heater (gas combustion amount) are adjusted according to the heating capacity command value l.
Control Pi.

In this way, the operating frequency fi of the compressor and the heating amount Pl of the refrigerant heater gradually increase, and the heating capacity increases.

Then, when the heating capacity command value l reaches the indoor load Li,
The heating capacity command value is changed according to the indoor load Li,
The heating capacity corresponding to the indoor load LL is maintained.

(Problem to be Solved by the Invention) However, in the heating operation described above, the specific volume of the refrigerant on the suction side of the compressor is small immediately after the start of the heating operation, so the refrigerant circulation amount is insufficient and the refrigeration cycle does not stabilize easily. It has the disadvantage of slow start-up.

This invention was made in view of the above circumstances,
The purpose is to provide an air conditioner that can obtain an appropriate amount of refrigerant circulation at the start of heating operation, thereby speeding up the start-up of heating.

[Structure of the Invention] (Means for Solving the Problems) A heat pump type refrigeration cycle in which a variable capacity compressor, a four-way valve, an outdoor heat exchanger, a pressure reducer, and an indoor heat exchanger are connected in sequence, and this refrigeration cycle. a refrigerant heater provided, a means for executing a heating operation by operating the compressor, switching a four-way valve, and operating the refrigerant heater; and at the start of the heating operation, the capacity of the compressor is immediately adjusted to correspond to the load. A means for setting the heating amount of the refrigerant heater to a value corresponding to the load and gradually increasing the heating amount of the refrigerant heater toward a value corresponding to the load, and after starting this, controlling the capacity of the compressor and the heating amount of the refrigerant heater respectively according to the load. and means to do so.

(Function) During heating operation, initially the capacity of the compressor is immediately set to a value corresponding to the load, and the heating amount of the refrigerant heater is gradually increased to a value corresponding to the load. Thereafter, the capacity of the compressor and the heating amount of the refrigerant heater are controlled depending on the load.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In Fig. 1, 1 is a variable capacity compressor;
A four-way valve 2, an outdoor heat exchanger 3, a check valve 4, an expansion valve 5, an indoor heat exchanger 6, and a check valve 7 are connected in sequence to constitute a heat pump type refrigeration cycle.

An electromagnetic on-off valve 8 and a refrigerant heater 9 are successively communicated from the communication portion between the check valve 4 and the expansion valve 5 to the refrigerant suction side piping of the compressor 1.

The refrigerant heater 9 is additionally equipped with a gas burner 10, which is connected via a proportional valve 11 to a fuel supply source (not shown).

Further, a refrigerant temperature sensor 12 is attached to the refrigerant outlet pipe of the refrigerant heater 9.

20 is a control unit that performs overall control of the air conditioner;
Removed from microcomputers and their peripheral circuits.

This control section 20 includes a four-way valve 2, an electromagnetic on-off valve 8, and a proportional valve 1.
1. Connect the operation unit 21, indoor temperature sensor 22, and inverter circuit 23.

The inverter circuit 23 has AC 1! The voltage of the source 24 is rectified, converted into an alternating current voltage of a predetermined frequency and level by switching, and supplied to the compressor 1 as driving power.

In addition to normal cooling operation control, the control unit 20 operates the compressor 1, switches the four-way valve 2, opens the electromagnetic on-off valve 8,
and a functional means for executing a heating operation by operating the refrigerant heater 9 (combustion of the gas burner 10), and for immediately adjusting the operating frequency of the compressor 1 (output frequency of the inverter circuit 23) to correspond to the load at the start of the heating operation. a functional means that gradually increases the heating amount of the refrigerant heater 9 (the combustion amount of the gas burner 10) toward a value corresponding to the load;
After this start, the operating frequency of the compressor 1 and the refrigerant heater 9
and functional means for controlling the heating amount of each according to the load.

Next, the operation of the above configuration will be explained with reference to FIGS. 2 and 3.

When the operation unit 21 performs an operation to start cooling operation, the control unit 2
0 drives the inverter circuit 23 and the compressor 1 is started. Furthermore, the control unit 20 closes the electromagnetic on-off valve 8 and causes the refrigerant to flow in the direction of the solid arrow shown in the figure to form a cooling cycle, so that the outdoor heat exchanger 3 is used as a condenser and the indoor heat exchanger 6 is used as an evaporator. make it work

In other words, cold air is blown into the room.

When the heating operation is started using the operation unit 21, the control unit 2
0 drives the inverter circuit 23 and the compressor 1 is started. Further, the control unit 2o operates the refrigerant heater 9, switches the four-way valve 2, opens the electromagnetic on-off valve 8, and causes the refrigerant to flow in the direction of the broken line arrow in the figure to form a heating cycle, thereby forming a heating cycle in the room. The heat exchanger 6 acts as a condenser, and the refrigerant heater 9 acts as an evaporator. In other words, warm air is blown into the room.

In this heating operation, the control unit 20 performs the following control.

When the start operation is performed, the operating frequency of the compressor 1 (output frequency of the inverter circuit 23) is immediately set to a value f corresponding to the load.

It also outputs a heating capacity command value i that increases by one step at predetermined time intervals based on the timer count. When this heating capacity command value i is output, the heating capacity command value i
Accordingly, the opening degree of the proportional valve 11, that is, the amount of heating of the refrigerant heater 9 (the amount of combustion of the gas par 10) Pi is set.

In this way, with the compressor 1 set to the operating frequency f corresponding to the load, the heating amount Pi of the refrigerant heater 9 gradually increases, and the heating capacity increases.

After that, when the heating capacity command value i reaches the indoor load Li,
Varying the heating capacity command value l according to the indoor load Lt,
The opening degree of the proportional valve 11, that is, the heating 11Pi of the refrigerant heater 9 is set in accordance with the heating capacity command value i. Note that for the compressor 1 as well, the operating frequency f corresponding to the load is set.

In this way, by immediately setting the capacity of compressor 1 to a value corresponding to the load at the start of heating operation, it is possible to obtain an appropriate amount of refrigerant circulation, and the refrigeration cycle is quickly stabilized, allowing heating to start up. can be accelerated. Therefore, comfort can be improved.

Note that the present invention is not limited to the above-mentioned embodiments, and various modifications can be made without changing the gist.

[Effect of the invention] As described above, according to the present invention, a variable capacity compressor,
A heat pump refrigeration cycle in which a four-way valve, an outdoor heat exchanger, a pressure reducer, and an indoor heat exchanger are connected in sequence, a refrigerant heater installed in this refrigeration cycle, operation of the compressor, switching of the four-way valve, and A means for performing heating operation by operating a refrigerant heater, and at the start of this heating operation, immediately setting the capacity of a compressor to a value corresponding to the load, and setting the heating amount of the refrigerant heater to a value corresponding to the load. The present invention is equipped with a means for gradually increasing the amount of refrigerant to the desired temperature, and a means for controlling the capacity of the compressor and the heating amount of the refrigerant heater, respectively, depending on the load after this start, so that the amount of refrigerant circulated is appropriate at the start of heating operation. This makes it possible to provide an air conditioner that can accelerate heating start-up.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the configuration of a refrigeration cycle and a control circuit in an embodiment of the present invention, Fig. 2 is a flowchart for explaining the operation of the embodiment, and Fig. 3 is an operating frequency in the embodiment. Figure 4 is a flowchart for explaining heating operation control of a conventional air conditioner, and Figure 5 is a diagram showing the operating frequency and proportional valve opening of the air conditioner shown in Figure 4. FIG. 1... Compressor, 2... Four-way valve, 3... Outdoor heat exchanger, 5... Expansion valve (pressure reducer), 6... Indoor heat exchanger, 8... Solenoid on-off valve , 9... Refrigerant heater, 10...
・Gas burner, 11...proportional valve, 20...control unit,
23...Inverter circuit.

Claims (1)

[Claims] A heat pump type refrigeration cycle consisting of a variable capacity compressor, a four-way valve, an outdoor heat exchanger, a pressure reducer, and an indoor heat exchanger connected in sequence, a refrigerant heater installed in this refrigeration cycle, the operation of the compressor, and a four-way Means for performing heating operation by switching valves and operating a refrigerant heater, and at the start of this heating operation, immediately setting the capacity of the compressor to a value corresponding to the load, and adjusting the heating amount of the refrigerant heater to a value corresponding to the load. An air conditioner characterized by comprising means for gradually increasing the temperature to a value corresponding to .