JPH03211347A - Control device for air conditioner - Google Patents

Abstract

PURPOSE:To improve an accumulated heating capability under a low surrounding air temperature by a method wherein a pulse output mode for determining a rotational speed of each of an indoor fan and an outdoor fan and the valve travel of an expansion valve is changed over to those of a normal heating operation in response to an outdoor air temperature, an operating frequency and an indoor fan speed. CONSTITUTION:A frequency (f1) detected by an operating frequency detection means 3 of a compressor is compared with a predetermined frequency (fa) by a comparisn means B8 so as to discriminate an operating frequency. A speed (n1) detected by an indoor fan speed detection means 5 is compared with a predetermined speed (na) by a comparisn means C9 so as to discriminate an indoor fan speed. A calculation means 10 may receive a result of comparison from each of comparisn means A, B and C. In the event that there are a relation of the outdoor air temperature T1 < the predetermined temperature value Ta, a relation of the operating frequency (f1) > the predetermined frequency (fa) and a relation of the indoor fan speed (n1) >= the predetermined speed (na), each of the outdoor fan speed and the indoor fan speed is increased by one step and a pulse output mode is changed over to reduce the valve travel of an expansion valve. With such an arrangement, it is possible to restrict a frosting under a low temperature operation, blown up hot air 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, pulse output corresponds to the rotational speed of the indoor/outdoor fan and the operation (drive) frequency of the expansion valve during heating operation (from one defrosting operation to the next defrosting operation). The mode is
The control content was always the same regardless of the outside temperature.

(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 problems, and when the outdoor temperature during heating operation is below a certain specified temperature, the operating frequency is above the specified frequency, and the indoor fan speed is above the specified speed, the load An object of the present invention is to provide a control device that performs corresponding control.

(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, a compressor operating frequency detecting means and a comparing means B that compares the detected frequency with a preset specified frequency and outputs the result, an indoor fan speed detecting means and a preset frequency with the detected speed. Comparison means C that compares the speed with the specified speed and outputs the result; calculation means that calculates based on each output value of comparison means A, B, and C and outputs a required signal; and the output signal of this calculation means. , outdoor fan speed switching means for switching the outdoor fan speed, pulse output mode switching means for switching the opening degree of the expansion valve corresponding to the operating frequency of the compressor, and indoor fan speed switching means for switching the indoor fan speed.

(Function) With the above configuration, when the outdoor temperature is below a certain specified temperature, the operating frequency is above the specified frequency, and the indoor fan speed is above the specified speed, the indoor and outdoor fan speed settings are set to normal. The pulse output mode is switched to a direction that increases the opening degree of the expansion valve compared to during heating operation and reduces the opening degree of the expansion valve.

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, in which numeral 1 denotes an outdoor temperature detection means, and 7 compares the detected temperature with a preset outdoor temperature setting value 2. Comparison means A outputs the results, 3 is compressor operating frequency detection means, 8 is the detected frequency and preset specified frequency 4
5 is an indoor fan speed detection means, and 9 is a comparison means C110 which compares the detected speed with a preset specified speed 6 and outputs the result. Calculating means for calculating based on each output value of means A, B, and C and outputting a required signal, 11゜12, 13
are an outdoor fan speed switching means for switching the outdoor fan speed, a pulse output mode switching means for switching the opening degree of the expansion valve corresponding to the operating frequency of the compressor, and an indoor fan for switching the indoor fan speed, respectively, based on the output signal of the calculation means 10. Speed switching means; 14, drive means A for driving the outdoor fan 17 in response to a control signal from the outdoor fan speed switching means 11; 15, drive means B for driving the expansion valve 18 in response to a control signal from the pulse output mode switching means 12; The indoor fan 1 is controlled by the control signal of the indoor fan speed switching means 13.
This is driving means C for driving 9.

Next, the operation of this implementation 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 outdoor temperature T1 sampled by the outdoor temperature detection means 1 and the preset outdoor temperature set value Ta are compared by the comparing means A7, and it is determined whether the outdoor temperature T1 is lower than the temperature set value Ta. Determine (step 1).

Next, the comparison means B8 compares the frequency 11 detected by the operating frequency detection means 3 of the compressor with a preset specified frequency fa to determine the operating frequency (step 2), and furthermore, the indoor fan speed detection means The comparison means C9 compares the speed n1 detected in step 5 with a preset specified speed na to determine the indoor fan speed (step 3).

The calculation means IO receives the comparison results from each comparison means A, B, and C, and determines that the outdoor temperature T+<temperature set value Ta, operating frequency/
1> When the specified frequency /a and the specified speed na above the indoor fan speed nl, increase the outdoor fan speed from v1 to v2 and the indoor fan speed from N to N2 by one step each, and increase the opening degree of the expansion valve. Switch the pulse output mode from P1 to P2 in the direction of narrowing down. In other cases, Vly N
Controlled by rt Pt.

(Effects of the Invention) As explained above, according to the present invention, the pulse output mode, which determines the speed of the indoor/outdoor fan and the opening degree of the expansion valve, is changed from normal heating to By changing the operation, 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... Compressor operating frequency detection means, 5... Indoor fan speed detection means,
7...Comparison means A, 8...Comparison means B,
9...Comparison means C110...Calculation means, 11...
- Outdoor fan speed switching means, 12...Pulse output mode switching means, 13...Indoor fan speed switching means, 14
...Driving means A, 15...Driving means B, 16...
Drive means C117...outdoor fan, 18...expansion valve, 19...indoor fan.

Claims (1)

[Scope of Claims] An outdoor temperature detection means and a comparison means A that compares the detected temperature with a preset outdoor temperature setting value and outputs the result, and a compressor operating frequency detection means and its detected frequency. Comparing means B that compares a preset specified frequency and outputs the result; Comparing means C that compares the indoor fan speed detection means and the detected speed with a preset specified speed and outputs the result. and the comparison means A, B, C
a calculation means for calculating and outputting a required signal based on each output value of the calculation means, an outdoor fan speed switching means for switching the outdoor fan speed based on the output signal of the calculation means, and an expansion valve corresponding to the operating frequency of the compressor. It consists of a pulse output mode switching means for switching the opening degree and an indoor fan speed switching means for switching the indoor fan speed, and when the outdoor temperature is below the set temperature, the operating frequency is above the specified frequency, and the indoor fan speed is above the specified speed. A control device for an air conditioner, characterized in that the indoor/outdoor fan speed is set higher than during normal heating operation, and the pulse output mode is switched in the direction of narrowing the opening degree of the expansion valve.