JPH04327744A - Air conditioner - Google Patents

Abstract

PURPOSE:To restore after restart of power supply the same operation as before service interruption irrespective of timing of the service interruption. CONSTITUTION:Each indoor unit is provided with a service interruption detecting means, a service interruption treating means, and an NVRAM storage control means. By controlling timing of NVRAM storage signals and protecting storage contents of the NVRAM, the same operation as before a service interruption can be restored irrespective of the timing of the service interruption.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner characterized in that, by storing the latest data in an NVRAM during a power outage, the operating state immediately before the power outage can be restored after the power is restored.

0002

2. Description of the Related Art FIG. 4 shows an example of a control circuit for an indoor unit in a conventional air conditioner. In the figure, 9 is a multiplex transmission line that serves as a medium for communication and power supply for each unit of this air conditioner, a DC power supply 13 that supplies power to the transmission line, and a choke that cuts off transmission signals (high frequency components) from the DC power supply 13. A coil 15 is provided. 14 is an AC power supply for this indoor unit, 12 is a microcomputer that controls this indoor unit, and includes a CPU 21, a memory 22, an input circuit 23, and an output circuit 2.
Consists of 4. 10 is a transmission circuit that converts the communication data of the transmission line 9 and the input/output data of the microcomputer 12, and 8 is an NVRAM that stores the latest data in the event of a power outage.
, 11 is a power supply circuit that receives power from the transmission line, and includes a rectifier diode 16 that unifies the polarity of the transmission line voltage, a three-terminal regulator 17, a capacitor 18 that removes noise from the input voltage of the three-terminal regulator, a voltage holding capacitor 19, and a transmission signal ( It consists of a choke coil 20 that blocks high frequency components. 1 is a power failure detection circuit that includes a step-down transformer 25, a rectifier diode 26, a smoothing capacitor 27, and a transistor 28.
, resistors 29 to 31, and a logic NOT circuit 34 that outputs a reset signal when the output of the power failure detection circuit 1 changes from a low level to a high level.

[0003] Normally, an air conditioner is operated by operating a remote controller. The remote controller transmits a transmission signal corresponding to its operation to the indoor unit via the transmission line 9. On the indoor unit side, the transmission circuit 10 receives this transmission signal, converts it into a signal that can be processed by the microcomputer 12, and transfers it to the microcomputer 12. Inside the microcomputer 12, the CPU 21 processes this signal using a program stored in the memory 22 in advance. At this time, each time data such as the operating mode, temperature setting, and address of the compatible remote controller change, these data are sent to the NVRA.
Write to volatile area of M8. If a power outage occurs here, the base voltage of the transistor 28, which is stepped down by the transformer 25, rectified by the rectifier diode 26, and smoothed by the capacitor 27 when the power is turned on, decreases and the transistor 28 is turned off, so that the input of the logic NOT circuit 34 changes from a low level to a high level. become NV
A reset signal is output to the store terminal of RAM8. Here, the NVRAM 8 stores the memory contents of the volatile area into the non-volatile area when the store signal changes from high level to low level. The NVRAM 8 receives this reset signal and stores the latest data written in the volatile area in the nonvolatile area. The DC power supply 13 that supplies power to the transmission line is designed to be able to hold the voltage sufficiently longer than the time required for this storage operation. When the power is restored, the NVRAM 8 returns the latest data stored in the non-volatile area to the volatile area. By reading this data, the microcomputer 12 obtains data that can restore the operating state. Through the above processing, even if the power goes out, the operating state immediately before the power outage is restored after the power is restored.

0004

[Problem to be Solved by the Invention] In a conventional air conditioner, the control circuit of the indoor unit outputs a store signal directly to the NVRAM in synchronization with the output of the power outage detection circuit as described above, so the microcomputer cannot detect the power outage. Even if there is a power outage, the output continues as long as its own power is maintained, so a large-capacity power supply that can maintain power for a sufficient period of time to store data in NVRAM is required, and the microcomputer also needs to be able to keep the NVRAM volatile. If there is a power outage while writing to the storage area, the data that is being written will be stored in the non-volatile area, and the data in the non-volatile area cannot be changed until the power is restored. There was a problem that the operating state could not be restored.

[0005] The present invention was made to solve these problems, and provides an air conditioner that can restore the previous operating state regardless of the timing of a power outage.

[0006]

[Means for Solving the Problems] The air conditioner according to the present invention has a power outage process in which when each indoor unit control circuit of the air conditioner receives a power outage detection signal from the power outage detection means, it controls the output control means to turn off all outputs. If a power outage is detected while data is being written to the volatile area of the NVRAM, the contents of the volatile area are stored in a non-volatile area after the data being written is completed, and then stored in a non-volatile area until the power is restored. This is provided with NVRAM store signal control means for prohibiting storage to the private area.

[0007]

[Operation] In this invention, by turning off all outputs when a power failure is detected in the own power supply, the power supply for control is held longer, and the latest data written in the volatile area of NVRAM is stored in the nonvolatile area. do. At this time, NVRAM
If data is being written to the volatile area, the contents of the volatile area are stored in the non-volatile area after the data being written is finished, and storage in the non-volatile area is prohibited until the power is restored. do.

[0008]

【Example】

Example 1. FIG. 1 is a block diagram of power outage control for an indoor unit showing an embodiment of an air conditioner according to the present invention. In the figure, 1 indicates a power outage detection means for detecting a power outage of the own power supply, and 8 indicates a volatile region and a nonvolatile region. An NVR that stores the memory contents of the volatile area in the non-volatile area by inputting a store signal.
AM, 6 inputs the store signal to this NVRAM 8.
VRAM storage means; 4 is an output control means for controlling all outputs of solenoid valves, fans, louvers, heaters, etc.; 7 is an output means for producing the above output under the control of the output control means; 2 is a power failure detection signal from the power failure detection means 1; When received, the output control means 4
3 is N.
If a power failure is detected while data is being written to the volatile area of VRAM8, the contents of the volatile area are stored in the non-volatile area after the data being written is completed.
This is an NVRAM store control means that prohibits storage in the nonvolatile area until the power is restored. FIG. 2 is an indoor unit control circuit showing an embodiment of an air conditioner according to the present invention. In FIG. 2, the same parts as those in the conventional example (FIG. 4) described above are given the same reference numerals, and the parts different from those in FIG. 4 will be mainly described to avoid redundant explanation. As is clear from a comparison between FIGS. 2 and 4, the output of the power failure detection circuit 1 is input to the microcomputer 12. Therefore, the logic NOT circuit 34 is deleted. The store signal of NVRAM8 is sent to the microcomputer 12.
given as the output of Here, an NVRAM write in progress flag is provided in the memory 22, which is set when the microcomputer 12 starts a write process to the volatile area of the NVRAM, and is reset when the process is finished.

FIG. 3 is a flowchart of indoor unit power outage control in the above embodiment. 35 is a step of determining the presence or absence of a power outage using the power failure detection circuit, 37 is a step of turning off all outputs in order to maintain the power of the microcomputer 12 for a longer period of time, and 38 is a step of determining the presence or absence of a power outage using the power failure detection circuit, and 38 is a step of determining whether or not there is a power outage by using the power failure detection circuit. Step 39 is to determine whether writing has been done to the volatile area of NVRAM 8. Step 39 is to retain data necessary for restoring operation after power is restored, such as the operating mode, temperature setting, and address of compatible remote controller, until power is restored. Step 40 outputs a store signal to the NVRAM 8 to store the above data in the volatile area in the non-volatile area and prohibits subsequent storage in the non-volatile area; 40 is a step to stop the unit; 41 is a step in which the current data is detected by the power failure detection circuit 1; a step of determining whether the power is out or has been restored;
42 releases the write protection in 39 and writes it to NVRAM8.
The data necessary for operation restoration is transferred to microcomputer 1.
2 is a step of reading the data into the memory 22, 43 is a step of initializing all outputs, 44 is a step of performing processing at the time of energization, and 36 is a step of writing data into the nonvolatile area of the NVRAM 8.

In FIG. 2, at the time of a power outage, the power outage detection circuit 1 outputs a high level signal as described above. When the CPU 21 in the microcomputer 12 receives this signal from the input circuit 23, it enters the above-mentioned power outage control process (FIG. 3) stored in advance in the memory 22 by an external interrupt. That is, all output is stopped in order to maintain the power supply of the microcomputer 12 for a longer period of time, and then it is confirmed that no writing is being performed in the volatile area of the NVRAM 8, and that the NVRAM writing flag is reset. After checking, the data necessary to restore operation after power is restored is N
The data is stored in the non-volatile area of VRAM 8, and storage in the non-volatile area is prohibited, the unit is stopped, and then power is monitored until power is restored. When the power is restored, the data stored in the non-volatile area of NVRAM 8 is read into the memory 22. . At this time, the write protection mentioned above is canceled. Then initialize all outputs,
It enters the processing state when power is applied. If the above-mentioned writing has been performed in step 38, the data writing step 36 is performed until it is completed. Note that the same processing is performed in the power recovery waiting state in step 41 even when the power is restored after the microcomputer 12 has been powered off and reset. Further, the power supply 13 of the transmission line 9 is designed to be able to maintain the control power supply voltage for a sufficient time to perform the above processing with all outputs stopped.

[0011]

[Effects of the Invention] As described above, according to the present invention, the power failure detection means, power failure processing means, and
The NVRAM store signal control means turns off all outputs in the event of a power outage, and if a power outage is detected while data is being written to the volatile area of NVRAM, the storage contents of the volatile area are changed to non-volatile after the data being written is completed. Since storage in the non-volatile area of NVRAM is prohibited until the power is restored, there is no need for a large-capacity power supply.
This has the effect that data can be reliably stored even if a power failure is detected while data is being written to the volatile area of the RAM.

[Brief explanation of drawings]

FIG. 1 is a block diagram of power outage control for an indoor unit showing an embodiment of an air conditioner according to the present invention.

FIG. 2 is an indoor unit control circuit showing an embodiment of an air conditioner according to the present invention.

FIG. 3 is a flowchart of indoor unit power outage control of an embodiment of the air conditioner according to the present invention.

FIG. 4 is an example of a control circuit for an indoor unit in a conventional air conditioner.

[Explanation of symbols]

1 Power outage detection means (circuit) 2 Power outage processing means 3 NVRAM store control means 4 Output control means 6 NVRAM store means 7 Output means 8 NVRAM 9 Multiplex transmission line 10 Transmission circuit 11 Power supply circuit 12 Microcomputer 13 DC power supply 14 AC power supply

Claims (1)

[Claims] [Claim 1] Consisting of an outdoor unit, at least one indoor unit, at least one remote controller, and a multiplex transmission line (hereinafter abbreviated as transmission line) that serves as a medium for communication and power supply and reception, the indoor unit A memory (hereinafter referred to as NVRAM) has a volatile area and a non-volatile area, and stores the contents of the volatile area in the non-volatile area by inputting a store signal.
), the NV inputs the store signal to this NVRAM.
Equipped with a RAM storage means and an output control means for controlling all outputs of solenoid valves, fans, louvers, heaters, etc., the latest data is written to the volatile area of NVRAM every time the status of the indoor unit changes, and the data is transferred to the NVRAM when a power outage is detected. In an air conditioner that restores the operating state immediately before the power outage after the power is restored by storing the power in the nonvolatile area of the NVRAM and then prohibiting storage in the nonvolatile area of the NVRAM until the power is restored, the power outage detection signal from the power outage detection means is stored. power outage processing means for controlling the output control means to turn off all outputs when receiving the N;
If a power failure is detected while data is being written to the volatile area of VRAM, the contents of the volatile area are stored in the non-volatile area after the data being written is finished, and then stored in the non-volatile area of NVRAM until the power is restored. An air conditioner characterized by being provided with an NVRAM store control means for prohibiting storage into the NVRAM.