JPH04344028A - Controlling device for air conditioner - Google Patents

Abstract

PURPOSE:To restrict an increasing of temperature of refrigerant and to assure a safety characteristics in a control device for an air conditioner in which the refrigerant is heated by a combustion heat to perform a thermal transfer. CONSTITUTION:A control part 8 is comprised of a combustion control part 13 for comparing an amount of combustion of a combustion means 5 determined by the first calculation part 11 in reference to a sensing temperature of a room temperature sensing means 7 with an upper limit combustion amount set by the second calculation part 12 in response to the number of rotation of the motor 1 set by an air volume setting means 9, and controlling the combustion means 5 at a lower amount of combustion. As the number of rotation of the motor 1 is decreased and the refrigerant temperature is easily increased, the upper limit combustion amount is set low and the combustion amount is controlled in a range not exceeding this value.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an air conditioner that heats a refrigerant using combustion heat and transfers the heat.

0002

2. Description of the Related Art Conventionally, a control device for an air conditioner of this type includes an indoor heat exchanger 3, a refrigerant heat transfer means 4, which is blown by a fan 2 driven by a motor 1, as shown in FIG.
It is composed of a combustion means 5, a refrigerant heating heat exchanger 6, and the like.

In the above configuration, the refrigerant heated by the combustion means 5 and evaporated in the refrigerant heating heat exchanger 6 condenses in the indoor heat exchanger 3 and radiates heat, thereby performing heating. When performing heating, when the room temperature is lower than the temperature desired by the user, combustion is performed at the maximum capacity of the combustion means 5, and when the desired temperature is approached, combustion is performed as the temperature rises in order to keep the room temperature constant. reducing the amount.

0004

[Problems to be Solved by the Invention] In such a conventional air conditioner control device, the combustion amount of the combustion means 5 is automatically controlled according to the indoor temperature, but the air volume of the fan 2 is controlled depending on the usage. The user could switch according to his/her preference. Therefore, when the capacity of the combustion means 5 is constant, the lower the blown air volume and the higher the room temperature, the higher the blown air temperature becomes. In addition, when the blowout air volume is low, the longer the combustion continues at the maximum combustion amount, the more the blowout temperature will increase.
Continuing to operate in such a state poses a safety problem, as the refrigerant temperature rises and the rise in refrigerant pressure poses a risk of pipe rupture.

The present invention solves the above-mentioned conventional problems by lowering the rise in refrigerant temperature, preventing the rise in refrigerant pressure, and
The purpose of the present invention is to provide a control device for an air conditioner that is highly safe and does not cause pipes to burst.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an indoor heat exchanger that is blown by a fan driven by a motor, a refrigerant heat transfer means, and a refrigerant heating heat that is heated by a combustion means. The apparatus includes an exchanger, a room temperature detection means, and a control section that controls the rotation speed of the motor and the combustion amount of the combustion means, and the control section includes an air volume setting means that can set the rotation speed of the motor in multiple stages. , a first calculation section that calculates the combustion amount based on the temperature detected by the room temperature detection means, and a second calculation section that calculates the upper limit value of the combustion amount according to the set value of the air volume setting means.
It has a calculation section and a combustion control section that controls the combustion amount of the combustion means using the lower of the output values of the first calculation section and the second calculation section.

[0007]

[Operation] In the above configuration, the second calculation section sets the upper limit value of the combustion amount of the combustion means lower as the set rotation speed of the air volume setting means becomes lower, and adjusts the upper limit value of the combustion amount of the combustion means according to the room temperature within a range that does not exceed this upper limit combustion amount. Since the combustion amount is controlled, even if the set rotation speed of the motor is low, an increase in refrigerant temperature can be prevented.

[0008]

[Example] An example of the present invention will be described below with reference to FIGS. 1 to 5.
This will be explained with reference to. In this embodiment, the same components as those shown in the above-mentioned conventional example will be described with the same reference numerals.

As shown in the figure, the refrigerant circuit includes an indoor heat exchanger 3 which is blown by a fan 2 driven by a motor 1, and a refrigerant heat transfer means 4 which uses a pressure difference to transfer heat without power.
and a refrigerant heating heat exchanger 6 heated by the combustion means 5
A room temperature detection means 7 is provided on the windward side of the indoor heat exchanger 3. Reference numeral 8 denotes a control unit that controls the rotational speed of the motor 1 and the combustion amount of the combustion means 5. The control section 8 includes an air volume setting means 9 that can set the rotation speed NS of the motor 1 in multiple stages, a motor drive section 10 that drives the motor 1 at the set rotation speed NS of the air volume setting means 9, and a temperature detected by the room temperature detection means 7. A first calculation section 11 calculates the combustion amount QO from TR, and a second calculation section 12 calculates the upper limit combustion amount QX according to the set rotational speed NS of the air volume setting means 9. It is composed of a combustion control section 13 that controls the combustion means 5 according to the combustion amount Q.

In the above configuration, the liquid refrigerant sent from the refrigerant heat transfer means 4 is heated by the refrigerant heating heat exchanger 6, and the saturated gas becomes a two-phase state and enters the indoor heat exchanger 3, where it radiates heat indoors. As a result, it becomes a supercooled liquid refrigerant and exits the indoor heat exchanger 3. Furthermore, the refrigerant is circulated through the refrigerant circuit by being sent by the refrigerant heat transfer means 4. FIG. 2 shows an operation flowchart. That is, when the operation starts, the motor 1 is driven at the rotation speed NS set by the user, and then the combustion amount QO is determined from the first calculation section 11 and the room temperature TR.
Calculate.

FIG. 3 shows the detected temperature TR of the room temperature detection means 7.
That is, it is a diagram showing the relationship between the room temperature TR and the combustion amount QO based on the calculation result of the first calculation section 11. T1, T2
, T3 vary depending on the set temperature set by the user, and are controlled to match the set temperature by switching the combustion amount QO according to the room temperature TR. As shown in the figure, when the room temperature TR is less than T1, the maximum combustion amount QH of the combustion means 5 is output, and the room temperature TR becomes T1.
1, in order to make the room temperature TR match the set temperature, the value of the combustion amount QO is gradually decreased as the room temperature TR rises, and when the room temperature TR reaches T2, the lower limit combustion amount QL of the combustion means 5 is output. Even if the combustion amount QO reaches QL, the room temperature continues to rise and reaches T3, and the combustion amount Q
Outputs O = 0 and stops combustion. Next, the second calculation unit 12 calculates the upper limit combustion amount QX from the set rotational speed NS.

FIG. 4 shows the set rotation speed NS of the air volume setting means 9.
and the upper limit combustion amount QX based on the calculation result of the second calculation unit 12.
FIG. As shown in the figure, the set rotation speed N
As the value of X becomes smaller, the value of the upper limit combustion amount QX is also set smaller. The rotation speeds that can be set with the air volume setting means 9 are NL, NM, NH (NL < NM < NH
), the values of the upper limit combustion amount QX are Ql , Qm , Qh (Ql < Qm < Qh )
It is determined that However, here Qh=QH. Next, the combustion control unit 13 compares the combustion amount QO and QX, and if the value of QX is lower, the combustion amount Q of the combustion means 5 becomes QX, and conversely, if QO is lower, the combustion amount Q of the combustion means 5 is compared.
The combustion amount Q of is controlled to QO.

FIG. 5 is a diagram showing the relationship between the room temperature TR and the output value of the combustion control section 13, that is, the combustion amount Q of the combustion means 5. When TR < T1, QO = QH, but
Since the value of QX at each set rotation speed is QX≦QH, the combustion amount Q of the combustion means 5 becomes the upper limit value QX of each set rotation speed NS. The room temperature at which the combustion amount Q begins to fall below QX is Tl when N=NL, Tm when NM, and Th=T1 when NH. When the room temperature exceeds Tl, the value of the combustion amount Q becomes the same regardless of the value of the set rotational speed NS. As described above, the second calculation unit 12 sets the combustion amount upper limit QX to a lower value as the set rotational speed NS of the air volume setting means 9 becomes smaller. Therefore, even at low airflow times when the refrigerant temperature tends to rise, the rise in the refrigerant temperature is suppressed and heating operation is possible without causing dangers such as pressure rise. Thereafter, the motor 1 and the combustion means 5 repeat the above operation until the operation is stopped.

[0014]

As described above, according to the air conditioner control device of the present invention, the upper limit value of the combustion amount is determined according to the rotational speed of the motor set by the air volume setting means. Safe operation is possible without pressure rise and rupture of pipes.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a control device for an air conditioner according to an embodiment of the present invention.

[Figure 2] Operation flowchart of the control device

[Figure 3] Relationship diagram between room temperature and combustion amount of the control device

[Figure 4] Relationship diagram between the set rotation speed of the motor and the upper limit combustion amount of the control device

[Figure 5] Relationship diagram between room temperature and combustion amount of the control device

[Figure 6]
Block configuration diagram of a conventional air conditioner control device

[Explanation of symbols]

1 Motor 2 Fan 3 Indoor heat exchanger 4 Refrigerant heat transfer means 5　Combustion means 6 Refrigerant heating heat exchanger 7 Room temperature detection means 8 Control section 9 Air volume setting means 11 First calculation section 12 Second calculation section 13 Combustion control section

Claims (1)

[Claims] 1. An indoor heat exchanger that is blown by a fan driven by a motor, a refrigerant heat transfer means, a refrigerant heating heat exchanger that is heated by a combustion means, and a room temperature detection means,
The controller includes a control section that controls the rotation speed of the motor and the combustion amount of the combustion means, and the control section has air volume setting means that can set the rotation speed of the motor in multiple stages, and a temperature detected by the room temperature detection means. a first calculation section that calculates the combustion amount; a second calculation section that calculates the upper limit value of the combustion amount according to the setting value of the air volume setting means; and the lower output value of the first calculation section and the second calculation section. a combustion control section that controls the combustion amount of the combustion means using a value of .