JPH03211345A - Control device for air conditioner - Google Patents

Abstract

PURPOSE:To improve an accumulated heating capability under a low outdoor temperature condition by a method wherein a speed of each of an indoor fan and an outdoor fan and a flow rate of refrigerant in a pressure reducing device are changed from those of a normal heating operation in response to an outdoor air temperature, a temperature of an outdoor exchanger and an indoor fan speed. CONSTITUTION:A speed (n1) detected by an indoor fan speed detection means 5 is compared with a predetermined speed (na) by a comparing means C9 so as to discriminate the indoor fan speed. A calculating means 10 may receive a result of comparison from each of comparing means A, B and C. In the event that there are relation of an outdoor temperature T1 < a set temperature value, Ta, a relation of an outdoor heat exchanger temperature T2 < a set temperature value Tb and a relation of an indoor fan speed n1 >= a predetermined speed (na), each of the outdoor fan speed and the indoor fan speed is increased by one step so as to change-over a setting of a flow rate of a pressure reducing device. With such an arrangement, it is possible to restrict a frosting under a low temperature operation, blow out air of hot temperature and to improve an accumulated capability.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention distinguishes between normal heating operation of an air conditioner and heating operation when the outside temperature is particularly low (hereinafter referred to as low-temperature operation). The present invention relates to a control device for an air conditioner that performs good control.

(Conventional technology) In conventional air conditioners, the rotational speed of indoor and outdoor fans during heating operation (from one defrosting operation to the next defrosting operation) and the flow rate of refrigerant in a pressure reducing device vary depending on the outside temperature. Regardless, the control content was always the same.

(Problem to be solved by the invention) In this way, in conventional control, the indoor and outdoor fan speed settings during low-temperature operation are the same as during normal heating operation, so the temperature of the refrigerant discharged by the compressor during operation is (Discharge temperature) was also low as in normal heating operation, and even if the load in the room increased as in low-temperature operation, the heating capacity of the air conditioner could not cope with the load. In other words, there was a tendency for the integrated capacity, which represents the performance of one cycle from the start of low-temperature operation to the end of defrosting operation, in unit time, to decrease significantly.

The present invention solves the above-mentioned problems, and when the outdoor temperature and the outdoor heat exchanger temperature are each below a certain specified temperature during heating operation, and when the indoor fan speed is above the specified speed, load-based control is performed. An object of the present invention is to provide a control device that performs the following operations.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides an outdoor temperature detection means and a comparison means for comparing the detected temperature with a preset outdoor temperature setting value and outputting the result. A, an outdoor heat exchanger temperature detection means and a comparison means B that compares the detected temperature with a preset outdoor heat exchanger temperature setting value and outputs the result, and an indoor fan speed detection means and its detection speed. and a prescribed speed set in advance and outputting the result; a calculating means that calculates based on each output value of the comparing means A, B, and C and outputs a required signal; The apparatus includes an outdoor fan speed switching means for switching the outdoor fan speed, a pressure reducing device flow rate switching means for switching the flow rate of refrigerant in the pressure reducing device, and an indoor fan speed switching means for switching the indoor fan speed based on an output signal from the means.

(Function) With the above configuration, when the outdoor temperature and the outdoor heat exchanger temperature are each below a certain specified temperature, and when the indoor fan speed is above the specified speed, the indoor/outdoor fan speed setting is changed to normal heating. Increase the flow rate from that during operation, and change the refrigerant flow rate setting in the pressure reducing device.

This makes it possible to suppress frost formation during low-temperature operation, blow out high-temperature air, and improve integration capacity.

(Example) Hereinafter, embodiments will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. Reference numeral 1 denotes outdoor temperature detection means, and 7 compares the detected temperature with a preset outdoor temperature setting value 2. 3 is an outdoor heat exchanger temperature detection means, 8 is a comparison means A that outputs the result, and 8 is a comparison means B that compares the detected temperature with a preset outdoor heat exchanger temperature setting value 4 and outputs the result.
Reference numeral 5 denotes an indoor fan speed detection means; 9 a comparison means C110 for comparing the detected speed with a preset specified speed 6 and outputting the result; a comparison means C110 for calculating based on each output value of the comparison means A, B, and C; 11.1 arithmetic means for outputting a required signal;
2.13 are outdoor fan speed switching means for switching the outdoor fan speed, pressure reducing device flow rate switching means for switching the refrigerant flow rate in the pressure reducing device, and indoor fan speed switching means for switching the indoor fan speed, respectively, based on the output signal of the calculation means 10; Reference numeral 14 denotes a driving means A, 1 for driving the outdoor fan 17 according to a control signal of the outdoor fan speed switching means 11.
Reference numeral 5 denotes driving means B for controlling the pressure reducing apparatus flow rate 18 using a control signal from the pressure reducing apparatus flow rate switching means 12, and reference numeral 16 denotes a driving means C for driving the indoor fan 19 according to a control signal from the indoor fan speed switching means 13.

Next, the operation of this embodiment will be explained with reference to the flowchart of FIG. When heating operation is instructed using the remote control or operation panel, the indoor/outdoor fan and compressor start operating.

Here, the comparison means A7 compares the outdoor temperature T1 sampled by the outdoor temperature detection means 1 and the preset outdoor temperature value Ta, and determines whether the outdoor temperature T□ is lower than the temperature set value Ta. (Step 1).

Next, the comparison means B8 compares the detected temperature T2 sampled by the outdoor heat exchanger temperature detection means 3 with a preset outdoor heat exchanger temperature setting value Tb, and the outdoor heat exchanger temperature is determined (step 2). ).

Furthermore, in the same manner, the speed n1 detected by the indoor fan speed detecting means 5 and the preset specified speed na are compared by the comparing means C9 to determine the indoor fan speed (step 3).

The calculation means 10 receives the comparison results from each comparison means A, B, and C, and determines that the outdoor temperature T1<temperature set value Ta, the outdoor heat exchanger temperature T2<the temperature set value Tb, and the indoor fan speed n.
If 1≧specified speed na, change the outdoor fan speed to v1→
v2, the indoor fan speed is increased by one step from N1 to N2, and the flow rate setting of the pressure reducing device is switched from P to P2. In other cases, it is controlled by,V,,N,,P,.

(Effects of the Invention) As explained above, according to the present invention, the speed of the indoor/outdoor fan and the flow rate of the refrigerant in the pressure reducing device are adjusted to the normal heating operation depending on the conditions of the outdoor temperature, the outdoor heat exchanger temperature, and the indoor fan speed. By changing this, the cumulative heating capacity can be improved, especially when the outside temperature is low.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of an embodiment of the present invention.
It is a flowchart of the same example. 1...Outdoor temperature detection means, 3...Outdoor heat exchanger temperature detection means, 5...Indoor fan speed detection means, 7...Comparison means A, 8...Comparison means B,
9... Comparison means C, 10... Calculation means, 11.
... Outdoor fan speed switching means, 12... Pressure reducing device flow rate switching means, 13... Indoor fan speed switching means, 14.
...Driving means, l 15...Driving means B, 16...
- Drive means C117...outdoor fan, 18...pressure reducing device flow rate, 19...indoor fan.

Claims (1)

[Claims] an outdoor temperature detection means and a comparison means A that compares the detected temperature with a preset outdoor temperature set value and outputs the result; an outdoor heat exchanger temperature detection means and the detected temperature with the preset outdoor temperature; Comparing means B for comparing the exchanger temperature set value and outputting the result; Comparing means C for comparing the indoor fan speed detecting means and the detected speed with a preset specified speed and outputting the result. , the comparison means A
, B, C, and an outdoor fan speed switching means for switching the outdoor fan speed based on the output signal of the calculating means; and an outdoor fan speed switching means for switching the refrigerant flow rate in the pressure reducing device. It consists of a pressure reducing device flow rate switching means and an indoor fan speed switching means for switching the indoor fan speed, and when the outdoor temperature and the outdoor heat exchanger temperature are each below the set temperature and the indoor fan speed is above the specified speed, the indoor/outdoor fan is switched on. A control device for an air conditioner, characterized in that the speed is increased compared to that during normal heating operation, and the flow rate setting of a refrigerant in a pressure reducing device is switched.