JP3011486B2 - Failure prediction and alarm system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a failure prediction and alarm system suitable for a refrigerator for storing goods at a low temperature, such as a freezer, a refrigerator and a refrigerated showcase.

[0002]

2. Description of the Related Art Conventionally, in the above-mentioned various types of cooling devices such as freezers and refrigerators, when the temperature in the refrigerator rises, a protection device (overload relay) for a refrigerator operates, or a short circuit occurs. Employs a system that immediately issues an alarm to notify an abnormality.

[0003]

However, this method is
Since this is a notification that an abnormality has already occurred, unless the processing is performed immediately, the contents will be useless. Therefore, the user is forced to take an urgent action, and the burden is large.

[0004] In addition, there are many problems such that the alarm is merely a mere notification of an abnormality, and the details of the failure cannot be known without going to the site and investigating.

[0005] Therefore, the present invention provides, for example, whether or not each component constituting a refrigeration system is exhibiting its function smoothly.
Alternatively, the responsiveness of the operation is monitored, and if the state of functional deterioration or slow responsiveness continues, it is predicted that a failure will occur, and a first-stage warning prompting an inspection is performed. If the corresponding processing is not performed, the second step is to provide a failure prediction and alarm system that issues a two-step alarm that issues a warning that a failure or abnormality has occurred, thereby ensuring that the refrigeration system operates smoothly. And

[0006]

SUMMARY OF THE INVENTION The present invention comprises means for determining whether or not various working parts constituting an apparatus are functioning normally, and, when the means determines that the functions are insufficient, In the failure / alarm system including a two-stage notification control means for performing a first-stage warning display relating to the corresponding operating component and performing a second-stage failure alarm display when a failure has occurred, A compressor connected to a pipe to form a refrigerant circuit, a condenser, a refrigeration system including an evaporator, etc., and a filter and a condenser fan motor attached to the condenser are provided. A condenser temperature measuring means for measuring, a fan motor temperature measuring means for measuring the temperature of the fan motor, and a compressor overload protection device which operates by detecting an overload of the compressor; Exceeds the set standard, If the overload protection device compressor is operating, and the warning to that effect is determined that the fan motor failure,
When the overload protection device of the compressor does not operate, a means for judging that the fan motor is clogged and issuing a warning to that effect, and when the temperature of the condenser is within the set reference and the fan motor temperature is at a certain reference value. When the temperature becomes equal to or higher than the temperature, a means for predicting and determining the life of the fan motor and issuing a warning to that effect is provided.

Further , the present invention provides a means for determining whether or not various operating parts constituting a certain device are functioning normally, and, when the means determines that the function is insufficient, the corresponding operation is performed. In the failure / warning system, which has a two-stage notification control means for performing a first-stage warning display on parts and performing a second-stage failure alarm display when a failure occurs, the failure tubes are sequentially connected by refrigerant pipes. A refrigerating device comprising a compressor, a condenser, an evaporator and the like forming a refrigerant circuit, and a temperature controller for detecting the temperature in the refrigerator cooled by the refrigerating device and controlling the operation of the refrigerating device. A relay unit that operates based on the temperature controller, compares the number of times of operation of the temperature controller with the number of operations of the relay unit, and notifies a failure of the relay unit when there is a difference between both the number of operations. With means for judgment That.

[0008]

[0009]

[Function] The refrigeration unit operates, and the compressor, condenser, and evaporator
For example, it is determined whether or not various operating components constituting the refrigeration apparatus normally perform their functions. If any malfunctioning working part is found, it is warned before it completely fails. In other words, failure prediction is possible, and prompts the user to take immediate action to remove the failure. If this warning is ignored and no action is taken to cause a failure, the failure is displayed and an alarm is issued, and the working parts are repaired or replaced. With such a two-stage notification system, the operation management of the device can be performed perfectly.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. In the embodiment, the compressor, the condenser, the decompression device, the evaporator, etc., which are components that constitute the refrigerating device by being sequentially connected by the pipe line, the function is not sufficiently exhibited particularly in the case of filter clogging and the like. The following description focuses on condensers that often fail.

If the condenser is clogged with dust and left in this state for a long time, the ambient temperature of the condenser fan motor rises, the temperature of the bearings rises, and the oil deteriorates. It leads to coil burning.

Further, when lint or the like is tangled around the fan motor, air is not sufficiently supplied to the condenser, the temperature of the condenser rises, and the load is large. The temperature rises, leading to fan motor failure.

[0013] The present invention is intended to prevent such clogging of the condenser,
At a stage where the rotation failure of the fan motor continues, the situation is notified in advance so that the user can take measures before the failure is completely caused.

First, a flow chart showing a basic control operation flow of the failure prediction and alarm system of the present invention shown in FIG. 1 will be described.

To see if the condenser is functioning properly, a condenser temperature sensor mounted on the surface of the condenser and measuring the temperature of the condenser is provided. Also, the condenser
It has a fan motor for sending outside air, and a filter for taking in clean air. Then, a fan motor temperature sensor attached to the case surface of the fan motor is provided to measure the temperature of the fan motor. In addition, an overload protection device (OLR) for the compressor is provided which detects the overload state of the compressor based on the compressor current and stops the compressor. Therefore, first, it is checked whether or not the condenser temperature has risen by the condenser temperature sensor (21). Specifically, an upper limit temperature (for example, 55 ° C.) that can be considered as abnormally high with respect to a temperature (for example, 45 ° C.) when the condenser operates normally and functions.
Is set, and it is determined whether or not the temperature exceeds the upper limit temperature (setting reference).

Here, the reason why the temperature of the condenser becomes considerably higher than usual is that the filter of the condenser is clogged with dust and the fan motor itself is stopped.

On the other hand, although the temperature of the condenser is not as high as described above, the fan motor temperature measured by the fan motor temperature sensor may be high. In such a case, for example, a thread or the like may be caught around the fan motor, causing the load on the fan motor to increase and the fan motor to be overheated. Or, there may be a case where the rotation operation of the fan motor is irregular and the life of the fan motor has expired.

In a situation where the temperature rise of the condenser does not exceed the upper limit temperature (NO at 21), the temperature rise of the fan motor is measured by a fan motor temperature sensor (22), and when the fan motor is functioning normally. Reference temperature (outside air temperature +
15 ° C.) (23). For example, if the outside temperature is 30
In the case of ° C., the reference temperature is 45 ° C. Therefore, 45
If the temperature exceeds (over) ° C, a warning about the life of the fan motor is issued (24). In this way, the removal of lint stuck on the user or the life of the fan motor has come, suggesting the necessity of replacement. In this case, the difference between the inlet air temperature and the outlet air temperature of the condenser may be compared with the measurement reference value as the reference temperature. If the condition that the condenser temperature exceeds the upper limit temperature (55 ° C.) continues (YES in 21), the load on the compressor increases, and the compressor current also increases.
The conditions for operating the compressor overload relay are set.

Therefore, it is next determined whether or not the compressor overload relay is operating (25). If the condition is not enough to activate the compressor overload relay (25
NO), it is predicted that the filter is clogged, and a warning of filter cleaning is issued (26). The user sees this warning and cleans the filter.

When the compressor overload relay has been activated (YES in step 25), an alarm is displayed to indicate that the fan motor has failed, and an alarm is issued (27).

The above-described various judgments, warnings, and alarms are performed by a control device (described later) including a microcomputer.

As described above, the failure prediction and alarm system of the present invention combines the temperature of the condenser, the temperature of the fan motor, and the operation of the overload protection device of the compressor, by combining
Notifies condenser clogging, fan motor life expectancy, and fan motor failure. The basic control contents are summarized as follows.

1. Measure the condenser temperature and compare with the upper limit temperature.

2. Check the operation of the overload protection device of the compressor. When the fan motor stops, the overload protection device operates.

3. When the overload protection device operates, it determines that the fan motor has failed and issues an alarm.

4. If the overload protection device does not operate, a quick warning (foreseeing) of clogging of the filter is issued.

5. When the temperature of the fan motor is measured and becomes equal to or higher than a certain reference temperature, the life of the fan motor is predicted and a warning is given (predicted).

Incidentally, the refrigerating apparatus is electrically controlled, and many electric parts are used for the control. To give an example, a temperature controller (thermostat) is provided to control ON / OFF of the compressor according to the temperature inside the showcase, and the power that operates integrally with the temperature controller is operated by operating this temperature controller. It is said that electrical components such as relays, starting relays, and electromagnetic contactors in three-phase devices are activated.

Therefore, it is also important to check whether or not these individual electric components are not malfunctioning and are operating normally. Recently, the concept of failure prediction has been developed. By comparing the voltage applied to the coil with the voltage when the relay contact operates,
There is a method of judging a failure when there is a deviation between the two (see Japanese Patent Application Laid-Open No. 2-299117). However, with this method, the operation of the component carrier can be confirmed,
There are drawbacks in that it is not possible to check the conditions in the sequence of coil operation, and two relays must be provided for each relay.

Therefore, a method for solving the above-mentioned drawbacks and improving the failure of individual electric components is proposed next.

FIG. 2 is a flowchart showing a control operation flow of the method.

In a normal state, the operation of the temperature controller (3)
When 1) is present, the operation (32) of the power relay or the operation (33) of the starting relay is a sequence in which the operation is performed integrally. Therefore, since these power relay, starting relay, and electromagnetic contactor operate integrally with the temperature controller, the operation of the temperature controller and the operation of the power relay, starting relay, and electromagnetic contactor are compared, and there is a difference between the two. When an error occurs, a failure indication is displayed.

Now, when the temperature controller operates, its signal a
Enters the comparison (34), and the operation signal b of the power relay corresponding thereto or the operation signal c of the start relay is also compared (3).
Enter 4). Therefore, the generation of a numerical difference between the a signal and the b signal (35) or the generation of a numerical difference between the a signal and the c signal (36) will be described. If there is a difference (35), a warning of a power relay failure is issued (37). In addition, the difference (3
If there is 6), a warning of the starting relay failure is issued.

For example, the thermostat is turned on / off five times in a certain period, and if it is normal, the power relay and the start relay are turned on / off five times accordingly, but the power relay is four times and the start relay is three times. If a difference occurs, it can be predicted that the power relay and the starting relay are out of order. In this way, when the power relay does not operate, there is an output, and when the starting relay does not operate, there is also an output.However, it is necessary to prevent chattering from being detected by hitting this output or to immediately issue a warning. In order not to put out
If the difference is not reached within a certain period of time,
Clear them all and count again.

Alternatively, a method may be used in which, when the value exceeds the reference value, an alarm is displayed immediately indicating that a failure has occurred.

Thus, the failure of the relay contact component can be predicted. FIG. 3 is a block circuit diagram of a control device for controlling the failure prediction / warning system of the present invention described with reference to FIGS. Reference numeral 1 denotes a CPU composed of a microcomputer.
Operation signals of a temperature controller (thermostat) 2 and an overload protection device (OLR) 3 for a compressor are input to the microcomputer. In addition, fan motor temperature sensor 4,
The measured temperature signal of the condenser temperature sensor 5 is also input. The operation of the power relay 6 and the starting relay 7 is controlled by a control signal from the CPU 1 which is output based on an operation signal from the thermostat 2. Further, an operation signal of the thermostat 2 and an operation signal of the power relay 6 and the start relay 7 are also input to the CPU 1, and comparison of the number of signals is performed by the CP.
This is performed at U1.

The CPU 1 is provided with many output lines, and is connected to a fan motor failure warning lamp 8, a fan motor life warning lamp 9, a filter cleaning warning lamp 10, and a condenser temperature rise lamp 11. When the fan motor failure alarm lamp 8 is turned on, the alarm buzzer 12 also sounds.

Further, a power relay failure warning lamp 13 and a start relay failure warning lamp 14 are provided for failure prediction and failure notification of the power relay 6 and the start relay 7, and a power relay failure display lamp 15 and a start relay failure display. A lamp 16 is provided. When the power relay 6 and the starting relay 7 fail, the alarm buzzer 12 also sounds.

[0039]

As described above, according to the present invention, the refrigeration equipment
Various functional parts such as compressor, condenser, evaporator, etc.
Equipment and compressor protection device, condenser temperature measuring means and condenser
Related to operation control of refrigeration equipment such as fan motor temperature measurement means
At the stage before Waru electrical component fails completely, if there is a functional failure, to light the malfunction indicator lamp, and the warning, so that the prediction of a failure. When a failure occurs, a two-stage failure notification system is provided in which an alarm buzzer or the like sounds and an alarm is issued.

Therefore, the notification at the first stage prompts the user to perform a process before a failure occurs, and can smoothly drive the apparatus, which greatly contributes to the user. Also,
Since the content of the failure is clear, there is an advantage that the response can be promptly performed.

[Brief description of the drawings]

FIG. 1 shows a condenser, which is a functional part of a refrigerating apparatus, as an example.
Warns (predicts) filter cleaning and fan motor life,
5 is a flowchart showing a flow of a control operation of a failure prediction and warning system for performing a warning of a fan motor failure.

FIG. 2 is a flowchart showing a flow of a control operation of a failure detection system of an electric component (a contact component of a relay) for controlling the compressor, taking a compressor as one functional component of the refrigeration apparatus as an example.

FIG. 3 is a control block diagram of a failure prediction / warning system according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 CPU 2 thermostat 3 overload protection device 4 fan motor temperature sensor 5 condenser temperature sensor 6 power relay 7 starting relay 8 fan motor failure alarm lamp 9 fan motor life warning lamp 10 filter cleaning warning lamp 11 condenser temperature rise lamp 12 alarm Buzzer 13 Power relay failure warning lamp 14 Start relay failure warning lamp 15 Power relay failure display lamp 16 Start relay failure display lamp

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G08B 23/00-31/00 F25D 23/00

Claims (2)

(57) [Claims] 1. A means for judging whether or not various operating parts constituting a certain device are functioning normally, and, when it is judged that the functions are insufficient, a means for judging the corresponding operating part In a failure and alarm system including a two-stage notification control means for performing a first-stage warning display and performing a second-stage failure alarm display when a failure occurs, the refrigerant circuit is sequentially connected by a refrigerant pipe to form a refrigerant circuit. Forming compressor, condenser,
A refrigerating device including an evaporator, a filter provided in the condenser and a condenser fan motor, a condenser temperature measuring means for measuring the temperature of the condenser, and a fan for measuring the temperature of the fan motor Provide a motor temperature measuring means and a compressor overload protection device that operates by detecting the compressor overload, when the condenser temperature exceeds the set standard and the compressor overload protection device is activated Means to judge that the fan motor is faulty and warn of that, and when the overload protection device of the compressor does not operate, means for judging that the filter is clogged and giving a warning to that effect, and the temperature of the condenser. A failure prediction and warning system comprising means for predicting and judging the life of a fan motor when the fan motor temperature becomes equal to or higher than a certain reference temperature within a set reference, and issuing a warning to that effect. 2. A means for judging whether or not various working parts constituting a certain device are functioning normally, and, when the means judges that the working parts are insufficient, the second working part relating to the corresponding working part is determined. In a failure and alarm system including a two-stage notification control means for performing a first-stage warning display and performing a second-stage failure alarm display when a failure occurs, the refrigerant circuit is sequentially connected by a refrigerant pipe to form a refrigerant circuit. Forming compressor, condenser,
A refrigerating device including an evaporator and the like, a temperature controller for detecting the temperature in the refrigerator cooled by the refrigerating device and controlling the operation of the refrigerating device, and relay means operating based on the temperature controller; Compare the number of times of operation of the temperature controller and the number of times of operation of the relay means, and when there is a difference between both the number of operations,
A failure prediction and alarm system, comprising: a determination unit that notifies a failure of the relay unit.