JPH04158142A - Controller of air conditioner - Google Patents

Abstract

PURPOSE:To secure pressure balance between high and low pressures by a method wherein only when a four-way valve is turned over at a time of starting of defrosting operation, operation frequency is reduced to a prescribed value before turning-over the four-way valve and an expansion valve is opened. CONSTITUTION:When a command of heating operation is given, expansion valve pulse value is set to a regulation pulse value P1 by an expansion valve pulse command output 43, an output means 44 and an expansion valve 45. If the pulse value is changed, operation frequency is regulated by operation frequency comparison, command output mode 46 and an output means 47. Regulation frequency is determined by comparing frequency f1 sampled from operation frequencies and regulation frequency (fa), and when the operation frequency (f1) is over the regulation frequency (fa), an operation frequency command is lowered and then the operation frequency is compared to the regulation frequency (fa) again. On the other hand, if the operation frequency (fl) is equal to or less than the regulation frequency (fa), a four-way valve is turned over by four-way valve turning-over signal output mode 48, an output means 49 and the four-way valve 40 from heating operation to defrosting operation.

Description

[Detailed Description of the Invention] Industrial Fields of Application The present invention (Table 1) relates to a defrosting operation control device for heating air conditioners at low temperatures; The reliability, noise, and vibration of the compressor when switching from heating to defrosting operation or from defrosting operation to heating operation were not properly controlled.Issues to be solved by the inventionConventional control When switching the compressor from heating operation to defrosting operation in continuous operation, the pressure balance between high and low pressure is maintained by regulating the operating frequency before switching the four-way valve. The pressure balance before switching can be ensured. When switching from heating operation to defrosting operation with the compressor in continuous operation, the sudden pressure change may generate noise or vibration from the indoor unit, or the compressor may overflow the refrigerant. There are problems with the reliability of the compressor, such as when the compressor is in a liquid compressed state.With conventional control, when switching the compressor from defrosting operation to heating operation in continuous operation, the pulse type expansion valve, etc. I did not fully understand the change control.I was unable to ensure the pressure balance between high and low pressure before switching the four-way valve, and when I switched the compressor from defrosting operation to heating operation in continuous operation, the compressor or refrigerant became liquid. In addition, with conventional control, when switching from defrosting operation to heating operation while the compressor is in continuous operation, an inverter model with variable operating frequency (Table 1) Since the defrosting operation frequency is high, regulating only the operating frequency cannot ensure the pressure balance between high and low pressures before switching the four-way valve, and when switching from defrosting operation to heating operation with the compressor in continuous operation. The present invention solves the above-mentioned problems, such as noise and vibration generated from the indoor unit due to sudden pressure changes, and problems with the reliability of the compressor in a liquid compression state where the compressor sucks refrigerant in a liquid state. It was an attempt to
When switching the compressor from heating operation to defrosting operation in continuous operation, in addition to the operating frequency, the purpose of the system is to ensure a pressure balance between high and low pressures before switching the four-way valve by changing the throttle of the pulse expansion valve, etc. The present invention also aims to ensure a pressure balance between high and low pressures before switching the four-way valve by changing the throttle of the pulse type expansion valve, etc. when switching the compressor from defrosting operation to heating operation in continuous operation. 4 In addition, the present invention (Yo) When switching the compressor from defrosting operation to heating operation in continuous operation,
In addition to the operating frequency, the purpose is to ensure a pressure balance between high and low pressures before switching the four-way valve by changing the throttle of the pulse expansion valve, etc.

Means for Solving the Problems In order to solve the above problems, the present invention has the following features: Only when switching the four-way valve at the start of defrosting operation, the operating frequency is increased to a certain certain frequency before switching the four-way valve, and the expansion valve is switched. By opening the compressor, the pressure balance between high and low pressures is ensured when switching from heating operation to defrosting operation in continuous operation of the compressor. By opening the expansion valve before switching the four-way valve, the pressure balance between high and low pressures is ensured when the compressor is switched from defrosting operation to heating operation in continuous operation. Only when switching the four-way valve at the end of operation, reduce the operating frequency to a certain level before switching the four-way valve, and open the expansion valve to switch the compressor from defrosting to heating operation in continuous operation. The present invention secures the pressure balance between high and low pressure when switching.The present invention lowers the operating frequency to a certain level before switching the four-way valve at the start of defrosting operation, and then opens the expansion valve to maintain the high and low pressure. In other words, to ensure the pressure balance of
Reduces the noise and vibration of the indoor unit when switching the compressor from heating operation to defrosting operation in continuous operation, and improves the reliability of the compressor.

In addition, the present invention (in other words, when switching from defrosting operation to heating operation with the compressor in continuous operation) opens the expansion valve before switching the four-way valve at the end of defrosting operation to ensure a pressure balance between high and low pressures. The present invention also improves the reliability of the compressor of In other words, it reduces the noise and vibration of the indoor unit when switching from defrosting operation to heating operation with the compressor in continuous operation, ensuring pressure balance.
EMBODIMENTS FOR IMPROVING THE RELIABILITY OF A COMPRESSOR Below, embodiments of the present invention will be described with reference to the drawings.

First of all, the first actual flow side of the present invention will be explained with reference to Fig. 4. When a heating operation instruction is issued by remote control or forced operation, the air conditioner starts operating, and if the heating operation continues thereafter, the air conditioner starts operating. A signal to start the defrosting operation is outputted by the frost operation start signal output mode 41 and the output means 42 (step 11).

Next Expansion valve pulse instruction output mode 43 and output means 44
, the expansion valve pulse value is set to the specified pulse value P1 by the expansion valve 45.
(Step 12). When the pulse value is changed, the operating frequency comparison, instruction output mode 46 and output means 4
The operating frequency is regulated by 7. The operating frequency is determined by comparing the sampling frequency f1 with the specified frequency fa (step 13). If the operating frequency f1 exceeds the specified frequency fa, the operating frequency is specified. is lowered (step 14) and compared again with the specified frequency fa. The force where the operating frequency f1 is equal to the specified frequency fa\
If it is less than that, the determination in step 13 is satisfied and the four-way valve is switched by the four-way valve switching signal output mode 48, the output means 49, and the four-way valve 410 to change from heating operation to defrosting operation (step 15).

Next Second Example A second embodiment of the present invention will be described with reference to FIG.

When the heating operation is instructed by the remote control or forced operation, the air conditioner starts operating, and when the heating operation is continued, the defrosting operation is performed. When the frost melts, the defrosting operation end signal output mode 51 and output means 52 A signal indicating the end of the defrosting operation is issued (step 21). Thereafter, the expansion valve pulse value is set to the specified pulse value P2 using the expansion valve pulse instruction output mode 53, the output means 54, and the expansion valve 55 (step 22). When the setting of the expansion valve pulse value is completed, the four-way valve is switched by the four-way valve switching signal output mode 56, the output means 57, and the four-way valve 58, and the defrosting operation is changed to the heating operation (step 23).

Next, the third embodiment of the present invention will be explained with reference to FIG. Defrosting operation end signal output modero 1 and output means 62 output a signal to end the defrosting operation (step 31).

Next, expansion valve pulse instruction output modero 3 and output means 64
, the expansion valve pulse value is set to the specified pulse value P2 by the expansion valve 65.
(step 32). When the pulse value is changed, the operating frequency comparison instruction output mode 6 and output means 6
The operating frequency is regulated by 7. The operating frequency is determined by comparing the sampling frequency f2 with the specified frequency fb (step 33). If the operating frequency f2 exceeds the specified frequency fb, the operating frequency is specified. is lowered (step 34) and compared with the specified frequency fb again. The force where the operating frequency f2 is equal to the specified frequency fb
If it is less than that, the determination in step 33 is satisfied, and the four-way valve is switched by the four-way valve switching signal output modero 8, the output means 69, and the four-way valve 610, and the defrosting operation is changed to the heating operation (step 35).

Finally, the defrosting operation end signal output mode in the second and third embodiments of the present invention will be explained with reference to FIG.
The comparison means 803 compares the outdoor heat exchanger piping temperature T1 detected in step 01 with the specified outdoor heat exchanger piping temperature Ta determined by the outdoor heat exchanger piping temperature setting value 802 (step 72). When step 72 is satisfied, the comparison means 806 compares the defrosting operation time t1 detected by the defrosting operation time detection means 804 and the specified defrosting operation time ta determined by the defrosting operation time setting value 805. (Step 73). If step 73 is not satisfied, perform the comparison in step 72 again (\
Power that step 72 is not satisfied\or step 73
When the conditions are satisfied (see table), the defrosting operation end signal is output.

Effects of the Invention Based on the content shown above, the present invention lowers the platoon frequency for switching the compressor from heating operation to defrosting operation to a certain constant frequency ζf in continuous operation, and opens the four-way valve after opening the expansion valve. By switching, it is possible to maintain a pressure balance between high and low pressures, prevent sudden pressure changes and liquid compression, reduce noise and vibration, and improve compressor reliability.

The present invention makes it possible to maintain a pressure balance between high and low pressures and prevent liquid compression by switching the four-way valve after opening the expansion valve when the compressor is switched from defrosting operation to heating operation in continuous operation. In addition, when switching the compressor from defrosting operation to heating operation in continuous operation, the present invention lowers the operating frequency to a certain certain frequency and opens the expansion valve. By switching the four-way valve after this, it is possible to maintain a pressure balance between high and low pressures, preventing sudden pressure changes and liquid compression, reducing noise and vibration, and improving compressor reliability.

[Brief explanation of drawings]

FIG. 1 is a control flowchart showing a first embodiment of the invention, FIG. 2 is a control flowchart showing a second embodiment of the invention, and FIG. 3 is a control flowchart showing a third embodiment of the invention. Flowchart of control, FIG. 4 shows a control block line operator according to the first embodiment of the present invention. FIG. 5 shows a control block line operator according to a second embodiment of the present invention. 7 is a control flowchart showing the defrosting operation end signal output mode of the second and third embodiments of the present invention, and FIG. 8 is a control block diagram showing the second and third embodiments of the present invention. Fig. 4 is a control block diagram showing the defrosting operation end signal output mode of the embodiment.
... Specified outdoor heat exchanger piping temperature, T1... Name of outdoor heat exchanger piping warm agent Patent attorney Akira Okaji and 2 other names (1) Figure 2 (2) Figure 3 (C) Stone Figure 7

Claims (3)

[Claims] (1) Output mode and output means for outputting the defrosting operation start signal, output mode and output means for comparing and instructing the operating frequency, pulse output mode and output means for controlling the opening degree of the expansion valve, switching signal for the four-way valve An air conditioner control device consisting of an output mode and an output means for outputting. (2) A detection means for detecting the outdoor heat exchanger piping temperature, a comparison means for comparing the detected temperature with a specified outdoor heat exchanger piping temperature, a detection means for detecting the defrosting operation time, and the detected time an output mode and an output means for outputting a defrosting operation end signal, a pulse output mode and an output means for controlling the opening degree of the expansion valve, and a comparison means for comparing the specified defrosting operation time, and a switching signal for the four-way valve. An air conditioner control device configured by an output mode and an output means. (3) The control device for an air conditioner according to claim (2), comprising an output mode and an output means for comparing and instructing operating frequencies.