JP2793081B2 - Temperature monitoring devices for showcases, etc. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature monitoring device for detecting a temperature in a refrigerator such as a showcase and generating an alarm output at a predetermined alarm temperature.

[0002]

2. Description of the Related Art Conventionally, in a showcase of this kind,
An alarm device that issues an alarm when an abnormality such as a failure of the device occurs and the temperature in the refrigerator rises is attached. Such an alarm device sets an internal temperature of a normal operation state of a showcase or the like, that is, an alarm temperature higher than the upper limit temperature that is cycled between the upper limit and the lower limit temperature, and the internal temperature is set to the alarm temperature. The alarm is issued when it reaches or exceeds, but during the so-called pull-down operation after installing the showcase etc. in the store and turning on the power, the temperature in the refrigerator is high even if it is not abnormal, Since no commodities have been displayed in the refrigerator yet, even if the temperature in the refrigerator is higher than the alarm temperature, the generation of the alarm is prohibited, thereby preventing the generation of unnecessary alarms.

[0003] An alarm prohibiting operation at the time of a pull-down operation of a conventional refrigerated showcase will be described with reference to FIG. In FIG. 4, T represents the temperature inside the refrigerator showcase (not shown), TS represents the preset temperature inside the refrigerator, such as + 5 ° C., and TE represents the alarm temperature, eg, + 15 ° C. Assuming that the showcase is installed and the power is turned on at time t1 in FIG. 4, the inside temperature T decreases by the operation of the cooling device, falls below the alarm temperature TE, and eventually reaches the inside set temperature TS. At a lower limit temperature such as + 3 ° C. lower than the internal set temperature TS, for example, the cooling device stops and starts to rise. Then, the cooling device restarts the operation at the upper limit temperature, for example, + 7 ° C., which is higher than the in-compartment set temperature TS.

The above-mentioned alarm device inhibits the generation of an alarm during an alarm inhibition period TM of, for example, 60 minutes after the power is turned on, and at time t1.
The warning prohibition at time t3 60 minutes after is released. When the showcase is installed, the internal temperature T is also room temperature,
During the pull-down operation, the temperature is naturally higher than the alarm temperature TE. However, the alarm is not issued during the alarm inhibition period TM because the generation of the alarm is prohibited.

[0005]

However, the above-mentioned prohibition of the alarm is executed without exception after the power is turned on. Therefore, for example, as shown in FIG. Even if the power is cut off and the power is restored immediately, the generation of the alarm is prohibited until time t2 when the alarm prohibition period TM elapses thereafter. Therefore, during the alarm prohibition period TM, a failure occurs in the equipment in the showcase, the internal temperature T rises, and no alarm is issued even when the temperature exceeds the alarm temperature TE.

In order to prevent an alarm from being issued when the temperature rises temporarily during defrosting or the like, an alarm is not normally issued immediately even when the internal temperature T exceeds the alarm temperature TE.
Since the alarm is issued after the elapse of the predetermined delay period TD such as 0 minute, even if the above-described abnormality occurs, the alarm is generated only after the alarm prohibition period TM and the delay period TD have elapsed from time t1. At a later time (after 70 minutes) at time t3,
At that time, the internal temperature T rises to an abnormally high temperature TH1 such as + 30 ° C., for example, and there is a problem that irreparable damage occurs to displayed foods and the like.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional technical problem, and is intended to prevent a temperature rise in a showcase or the like which can prevent an abnormal rise in temperature in a refrigerator due to an alarm prohibition performed after the power is turned on. It is an object to provide a monitoring device.

[0008]

According to the first aspect of the present invention, a temperature monitoring apparatus for a showcase or the like according to the present invention comprises a sensor for detecting an inside temperature of a showcase or the like; A control device 2 for comparing the temperature with the alarm temperature to generate an alarm output. The control device 2 prohibits the generation of the alarm output during a predetermined prohibition period after the power is turned on. It is characterized in that the prohibition of the generation of the alarm output is released based on the temperature state.

The temperature monitoring device 1 for a showcase or the like according to the second aspect of the present invention compares the sensor 4 for detecting the temperature inside the refrigerator such as a showcase with the temperature of the refrigerator based on the output of the sensor 4 and the alarm temperature. And a control device 2 for generating an alarm output. The control device 2 prohibits the generation of an alarm output during a predetermined prohibition period after the power is turned on, and the inside temperature does not change for a certain period during the prohibition period. In this case, the prohibition of the alarm output is released.

The temperature monitoring apparatus 1 for a showcase or the like according to the third aspect of the present invention compares a sensor 4 for detecting the temperature inside the refrigerator such as a showcase with an inside temperature based on an output of the sensor 4 and an alarm temperature. And a control device 2 for generating an alarm output. The control device 2 prohibits the generation of an alarm output during a predetermined prohibition period after the power is turned on, and also controls the temperature in the refrigerator during a prohibition period such as a showcase. When a normal operation state is set, the prohibition of the alarm output is released.

[0011]

According to the temperature monitoring device such as a showcase of the first aspect of the invention, the control device prohibits the generation of the alarm output during a predetermined prohibition period after the power is turned on. Therefore, no alarm is issued during the pull-down operation even if the internal temperature is high. on the other hand,
In the case where the power supply is instantaneously cut off while the showcase or the like is performing the cycle operation and the power is immediately turned on after being restored, the generation of the alarm output is prohibited. Monitor the temperature inside the chamber during the prohibition period,
Based on this, the prohibition of the generation of the alarm output is released. Therefore, even when an abnormality or the like of the device occurs during the prohibition period, the abnormality can be detected by detecting a change in the internal temperature, and the alarm can be quickly issued by canceling the prohibition of the alarm output.

Further, according to the temperature monitoring apparatus 1 such as a showcase of the second aspect of the present invention, similarly, it is possible to prevent the useless alarm from being generated during the pull-down operation, and to keep the temperature in the refrigerator for a certain period during the pull-down operation. If it does not change, the control device 2 quickly issues an alarm by canceling the prohibition of the alarm output. Therefore, for example, in the case where cooling is not performed due to equipment failure and the internal temperature does not decrease, even during the prohibition period, this can be canceled and an alarm can be issued immediately.

Further, according to the temperature monitoring apparatus 1 for a showcase or the like according to the third aspect of the present invention, it is possible to prevent the useless alarm from being generated during the pull-down operation and to perform the cycle operation of the showcase or the like. In a situation in which the power supply is momentarily cut off during the operation state and is immediately restored, the control device 2 releases the prohibition of the alarm output by turning the power supply on and the showcase or the like returns to the normal operation state. Therefore, even when a failure occurs in the device after the power supply is restored and the normal operation state is restored, the prohibition of the output of the alarm is released and the alarm can be quickly issued.

[0014]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of an electric circuit of a temperature monitor 1 such as a showcase of the present invention, and FIG. 2 is a flowchart showing a program of a microcomputer 3 constituting a controller 2 of the temperature monitor 1. In FIG. 1, the temperature monitoring device 1 includes a control device 2 and a sensor 4 (not shown) for detecting, for example, the temperature T in a refrigerator showcase. The control device 2 is a general-purpose microcomputer 3, A /
It comprises a D converter 5, a serial interface 6 connected to an external central management device (not shown) via a communication line, and a DC power supply 7 of the microcomputer 3.

The sensor 4 is connected to an A / D converter 5,
The internal temperature T, which is the output, is subjected to A / D conversion and input to the microcomputer 3. The microcomputer 3 communicates with the outside via the serial interface 6, and receives data of the alarm temperature TE, the alarm inhibition period TM, and the alarm delay period TD. The microcomputer 3 compares the inside temperature T based on the output of the sensor 4 with the alarm temperature TE. If the inside temperature T exceeds the alarm temperature TE, the microcomputer 3 generates an alarm output to the central management device. Send. The central management device is configured to receive the alarm output and issue an alarm.

Next, the operation of the temperature monitoring device 1 for inhibiting the generation of an alarm output will be described with reference to the time transition of the internal temperature T shown in FIGS. 3 and 4. Here, a temperature control device for a showcase (not shown) controls the operation of a cooling device (not shown) based on the inside temperature T. That is, the set temperature TS in the refrigerator
Is, for example, + 5 ° C., the temperature controller sets an upper limit temperature of + 7 ° C. and a lower limit temperature of + 3 ° C. above and below the temperature control device, and controls the operation of the cooling device between the upper limit temperature and the lower limit temperature. An operation is performed to average the temperature T and adjust the temperature T to the in-compartment set temperature TS.

First, if it is assumed that the power is turned on at time t1 in FIG. 4 after the showcase has been installed in the same manner as described above, the internal temperature T is naturally room temperature. Start up and start pull-down operation. Due to this pull-down operation, the internal temperature T decreases. On the other hand, the microcomputer 3 of the control device 2 of the temperature monitoring device 1 starts when the power is turned on after the installation, sets a pull-down flag in step S1 of FIG. The temperature T is input and the internal temperature at this time is stored as T1.
Next, in step S3, it is determined whether or not the pull-down flag has been set. Since the pull-down flag has been set, the process proceeds to step S4, and the inside temperature T is input again, and the inside temperature at this time is set to T2. Next, at step S5, it is determined whether or not the descending flag is set. Since the flag is initially reset, the process proceeds to step S6, and it is determined whether or not the ascending flag is set at this time. Since the rising flag is also reset at the beginning, the process proceeds to step S7, and it is determined whether or not T2 is lower than T1, that is, whether or not the inside temperature T has dropped.

As shown in FIG. 4, since the internal temperature T decreases, the process proceeds from step S7 to step S20, in which a lowering flag is set, and T2 is shifted to T1 and stored. Next, proceeding to step S10, it is determined whether or not the alarm prohibition period TM has elapsed since the power was turned on. If not, the process proceeds to step S11 to prohibit the generation of an alarm output, and proceeds to step S18. The process is executed, and the process returns to step S3. While the pull-down flag is set, the process proceeds from step S3 to step S4, in which the internal temperature T is input, the internal temperature at this time is stored as T2, and it is determined in step S5 whether the descending flag is set. Here, since it is set, the process proceeds to step S14 to determine whether or not T2 is higher than T1, that is, whether or not the internal temperature T is increasing.
The process proceeds to 0 and the same processing is repeated thereafter. If the alarm prohibition period TM has elapsed during this time, the process proceeds from step S10 to step S13 to reset the pull-down flag. Thereafter, the process directly proceeds from step S3 to step S18. That is, in a state where the internal temperature T is lowered by the pull-down operation, the generation of the alarm output is prohibited in step S11 until the internal temperature T is higher than the alarm temperature TE until the alarm prohibition period TM elapses.

Here, the inside temperature T falls below the alarm temperature TE and eventually reaches the inside set temperature TS, and reaches the lower limit temperature of + 3 ° C. at time t2 in FIG. 4 before the alarm prohibition period TM elapses. If so, the temperature control device stops the cooling device. As a result, the decrease of the internal temperature T stops, and the temperature starts to increase. Therefore, in step S14, T2 becomes higher than T1.
To reset the pull-down flag.
Then, the process directly proceeds to step S18 to release the prohibition of the alarm output. That is, even before the alarm prohibition period TM elapses, the prohibition of the generation of the alarm output is released when the internal temperature T reaches the lower limit temperature.

If the internal temperature T does not decrease even if the pull-down operation is started and there is no change, the process proceeds from step S5 to step S6, further proceeds from step S7 to step S8, and proceeds to step S9. In step S9, it is determined whether or not the unchanged state by the timer of the microcomputer 3 has been continued for 10 minutes. If the state has not been continued for 10 minutes, the process proceeds to step S10, and during the subsequent alarm prohibition period TM, Similarly, the generation of the alarm output is prohibited, but if the state of no change is continued for 10 minutes, the process proceeds from step S9 to step S13 to reset the pull-down flag. At this time, the microcomputer 3 naturally generates an alarm output because the internal temperature T is room temperature or at least higher than the alarm temperature TE. As a result, if the cooling device of the showcase is out of order and the internal temperature T does not decrease without exerting the cooling effect even by the pull-down operation after installation, the alarm inhibition period TM
Even before the time elapses, an alarm is issued and the user can be quickly alerted of the abnormality.

When the temperature control device stops the operation of the cooling device at the time point t2 when the internal temperature T reaches the lower limit temperature as described above, the internal temperature T rises and eventually rises to + 7 ° C.
When the upper limit temperature is reached, the operation of the cooling device is restarted, and thereafter, the cycle operation which is a normal operation state is repeated. If a power failure occurs momentarily at time t1 in FIG. 3 during the cycle operation in the normal operation state and the power supply recovers immediately, the microcomputer 3 resumes the control from the start in FIG. It is set again in S1. Then, similarly, the process proceeds to step S7, where T
It is determined whether 1 is higher than T2. If the power failure occurs during the rise of the internal temperature T, T1 is lower than T2.
2 is shifted to T1 and stored. Next, step S10
Then, it is determined whether or not the alarm prohibition period TM has elapsed from the time t1 in FIG. 3, and since it has not elapsed, the process proceeds to step S11, and similarly, the generation of the alarm output is prohibited.

Next, returning to step S3, the process proceeds to step S6 by the same processing. Since the rising flag is set, the process proceeds to step S16, and whether T2 is lower than T1, that is, if the internal temperature T It is determined whether or not the descent has started, and if the descent continues, the process proceeds to step S10, and the generation of an alarm output during the alarm inhibition period TM is inhibited thereafter. FIG.
At time t2, when the internal temperature T reaches the upper limit temperature and the temperature control device restarts the operation of the cooling device and the internal temperature T starts to decrease, the microcomputer 3 proceeds from step S16 to step S17 and pulls down. Reset the flag. As a result, similarly, step S11 is not performed thereafter, so that the prohibition of the alarm output is released. That is, if the normal operation state is performed after the instantaneous power failure, the prohibition of the alarm output is released in a very short period after the power is turned on.

If, for example, the cooling device fails immediately after time t2 in FIG. 3 and the cooling operation is not performed and the internal temperature T rises and exceeds the alarm temperature TE at time t3, the operation is started. At time t4 when the alarm delay time TD elapses, the microcomputer 3 issues an alarm output. The period from power-on to time t4 in FIG. 3 is the same as time t4 in FIG.
This is a period that is much shorter than the period up to 3. Therefore, if the temperature rise rate is the same, the internal temperature TH2 at the time when the alarm is issued in FIG. 3 is much lower than the temperature TH1 in FIG. 5, for example, + 10 ° C. It becomes the temperature before and after. That is, since an alarm can be issued at an extremely early time, damage to the displayed chilled food can be minimized.

In the embodiment, the temperature monitoring device 1 and the temperature control device are described as separate devices. However, as another process (step S18) of the microcomputer 3, the operation of the cooling device is controlled and the temperature in the refrigerator is controlled. T may be configured to be adjusted to the set temperature TS. Further, in the embodiment, the present invention is applied to a refrigerated showcase, but the present invention is not limited thereto, and the present invention is also effective for a home refrigerator or a prefabricated refrigerator.

[0025]

As described above in detail, according to the first aspect of the present invention, generation of an alarm output is prohibited during a predetermined prohibition period after the power is turned on, so that unnecessary generation of an alarm output during pull-down operation is prevented. can do. Furthermore, the control device monitors the state of the inside temperature during the prohibition period, and cancels the prohibition of the alarm output based on the monitoring result. By detecting the temperature state and canceling the prohibition of the alarm output, an alarm can be quickly issued.

According to the second aspect of the present invention, similarly, it is possible to prevent the use of an unnecessary alarm output during the pull-down operation, and when the internal temperature does not change for a certain period during the pull-down operation, the control device issues an alarm. An alarm is issued promptly by releasing the output prohibition. Therefore, for example, in a case where cooling is not performed due to equipment failure and the internal temperature does not decrease, the alarm can be released immediately and an alarm can be immediately issued even during the alarm prohibition period.

Further, according to the third aspect of the present invention, it is possible to prevent the generation of an unnecessary alarm during the pull-down operation.
In a situation where the power supply is instantaneously cut off in the normal operation state where the showcase or the like is performing the cycle operation and the power supply is restored immediately, the control device is turned into the normal operation state after the power supply is turned on. Releases the prohibition of the alarm output, so if the equipment is broken after the power is restored and returned to the normal operation state, the prohibition of the alarm output is released, and the alarm is quickly issued. Is what you can do.

[Brief description of the drawings]

FIG. 1 is a block diagram of an electric circuit of a temperature monitoring device such as a showcase of the present invention.

FIG. 2 is a flowchart showing a program of a microcomputer.

FIG. 3 is a diagram showing a time transition of a temperature in a refrigerator such as a showcase during a cycle operation.

FIG. 4 is a diagram showing a time transition of a temperature in a refrigerator such as a showcase during a pull-down operation.

FIG. 5 is a diagram showing a time transition of the internal temperature during a cycle operation of a conventional showcase or the like.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Temperature monitoring device 2 Control device 3 Microcomputer 4 Sensor

Claims (3)

(57) [Claims] 1. A temperature monitoring device for detecting an inside temperature of a showcase or the like and generating an alarm output at a predetermined alarm temperature, a sensor for detecting the inside temperature, and a sensor based on an output of the sensor. A control device for comparing the internal temperature with the alarm temperature to generate the alarm output, the control device prohibiting the generation of the alarm output during a predetermined prohibition period after power-on, and during the prohibition period. A temperature monitor for a showcase or the like, wherein the prohibition of the alarm output is released based on the state of the temperature in the refrigerator. 2. A temperature monitoring device for detecting an inside temperature of a storage such as a showcase and generating an alarm output at a predetermined alarm temperature, wherein a sensor for detecting the inside temperature and the storage based on an output of the sensor. A control device for comparing the internal temperature with the alarm temperature to generate the alarm output, the control device prohibiting the generation of the alarm output during a predetermined prohibition period after power-on, and during the prohibition period. A temperature monitor for a showcase or the like, wherein the prohibition of the generation of the alarm output is canceled when the internal temperature does not change for a certain period. 3. A temperature monitoring device for detecting a temperature in a refrigerator such as a showcase and generating an alarm output at a predetermined alarm temperature, wherein a sensor for detecting the temperature in the refrigerator, and the temperature of the refrigerator based on an output of the sensor. A control device for comparing the internal temperature with the alarm temperature to generate the alarm output, the control device prohibiting the generation of the alarm output during a predetermined prohibition period after power-on, and during the prohibition period. A temperature monitoring device for a showcase or the like, wherein the prohibition of the generation of the alarm output is released when the temperature in the refrigerator becomes a normal operation state of the showcase or the like.