JP4806853B2 - Water meter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water meter be installed in the conduit for water supply tap water.
[0002]
[Prior art]
Conventionally, this type of flow meter has been known as disclosed in JP-A-11-64055. The configuration will be described below with reference to FIG.
[0003]
As shown in FIG. 5, the flow rate calculation means 5 is based on the ultrasonic transducers 2 and 3 and the detection circuit 4 that transmit and receive ultrasonic waves to and from the flow path 1 and the propagation times T1 and T2 measured by the detection circuit 4. Then, the fluid flow rate is measured, and the fluid temperature is obtained by the temperature detecting means 6. The fluid usage state is monitored from the obtained flow rate and temperature, and the abnormality determination means 7 for determining the above and the notification means 8 for informing the outside when the abnormality is determined. Here, the arrow indicates the direction in which the fluid flows.
[0004]
In the above configuration, when the fluid temperature approaches the freezing temperature, the flow rate is reduced, so that it can be determined that the abnormal level is high and notification can be made, so that piping freezing can be prevented.
[0005]
[Problems to be solved by the invention]
However, the above-described conventional configuration has a problem that the discovery of freezing is delayed because an abnormality is discovered when the temperature of the fluid reaches around 0 ° C. or when the fluid freezes and the flow rate decreases.
[0006]
The present invention solves the above-described problems, and an object thereof is to prevent inconveniences such as freezing caused by a temperature drop.
[0007]
[Means for Solving the Problems]
In order to solve the conventional problem, a transmission / reception unit that transmits and receives a sound wave by propagating a sound wave in a fluid in a flow path, a flow rate detection unit that detects a flow rate from a propagation time of the transmission / reception of the sound wave, and a transmission / reception unit of the sound wave A temperature detection unit that detects the temperature of the fluid from the propagation time and a freeze prediction unit that predicts freezing from the temperature change of the temperature detection unit are provided.
[0008]
As a result, freezing can be predicted from the temperature change of the temperature detecting means, and freezing can be prevented in advance.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The water meter according to the present invention includes a transmission / reception unit that transmits and receives a sound wave by propagating a sound wave in a fluid in a flow path, a flow rate detection unit that detects a flow rate from a propagation time of transmission / reception of the sound wave, and propagation of transmission / reception of a sound wave A temperature detecting means for detecting the temperature of the fluid from the time, a time measuring means for measuring the time, a freezing predicting means for predicting a freezing time from a temporal temperature change of the temperature detecting means, an on-off valve for opening and closing the flow path, It has. And the on-off valve opens the flow path at the freezing time, and when freezing occurs in this time zone, the flow rate measuring unit of the flow rate detecting means is lengthened or the flow rate measurement is stopped. Thus, freezing can be prevented in advance.
[0010]
【Example】
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2, taking a water meter as an example.
[0011]
As shown in FIG. 1, a pair of ultrasonic transducers 10 and 11 that transmit and receive ultrasonic waves in the water in the flow path 9, a transmission and reception unit 12 that transmits and receives using the ultrasonic transducers 10 and 11, Flow rate detection means 13 for calculating a flow rate from the propagation time of ultrasonic waves transmitted and received by the transmission / reception means 12, Temperature detection means 14 for calculating an underwater temperature from propagation time of ultrasonic waves transmitted and received by the transmission / reception means 12, and the temperature The structure includes the freezing prediction means 15 for predicting freezing of water in the flow path from the temperature change of the detection means 14. And the time measuring means 16 which time-measures, the alerting | reporting means 17 which alert | reports various alarm situations, the opening / closing valve 18 as an opening / closing means which controls the opening / closing degree of a flow path, and the control means which drive-controls the said opening / closing valve 18 19 and a water meter comprising a battery 20 as a power source for supplying power to each of the above means. Here, 21 is a display for notifying the alarm, 22 is a communication means for notifying the alarm that the alarm has been left, and 23 is a stepping motor for driving the on-off valve.
[0012]
According to the above configuration, the propagation time tu transmitted from the ultrasonic transducer 10 on the upstream side of the flow and received and measured by the ultrasonic transducer 11 on the downstream side, and conversely, the ultrasonic transducer 11 on the downstream side. From the propagation time td transmitted and received by the ultrasonic transducer 12 on the upstream side, the flow velocity V is obtained and the flow rate detecting means 13 calculates the flow rate Q by multiplying the cross-sectional area of the flow path and a predetermined coefficient. calculate. Similarly, the temperature detection means 14 determines the sound velocity C from the propagation times tu and td. Then, the temperature T can be calculated from the obtained sound speed C.
[0013]
Then, the time t measured by the time measuring means and the temperature T detected by the temperature detecting means are stored at predetermined time intervals. From the stored time and temperature data, the time when the temperature falls below a predetermined temperature (for example, the water temperature falls below 0 ° C.) is predicted by the freeze prediction means. For example, as shown in FIG. 2, a time t3 at which the temperature is equal to or lower than the freezing temperature T0 is predicted by linear prediction from the temperature T1 at the time t1 and the temperature T2 at the time t2. If the predicted time t3 is within a predetermined time range (for example, within 0 to 9 o'clock), the possibility of freezing is strong, so an alarm is notified. However, if the predicted time is after a predetermined time (for example, 9 o'clock), the temperature is likely to rise, so the possibility of freezing is low. Therefore, no warning is given.
[0014]
The alarm may be at the time point predicted by the freeze prediction means or may be a little before the predicted freezing time. Moreover, after confirming freezing, a stronger alarm may be notified. For example, at the time of prediction, it can be notified by taking a method of displaying on a display device provided in a water meter or a method of displaying on a display device distant from the water meter. Furthermore, in the case of a strong alarm, not only the strength is displayed on the display unit, but also a notification is made by a method of notifying the person who manages it through the communication means. Then, by predicting when the freezing starts thawing and notifying at that time, it becomes possible to promptly perform the treatment after the freezing is thawed.
[0015]
Also, freezing can be predicted when the temperature change of the detected temperature is greater than or equal to a predetermined temperature change, that is, when the temperature has suddenly dropped from a specific temperature. In this case as well, an alarm is notified that there is a possibility of freezing. Even if there is no sudden temperature change, an alarm can be notified when the absolute temperature reaches a predetermined temperature (for example, 0 ° C. or less).
[0016]
In addition, by knowing in advance the possibility of freezing, freezing can be prevented by opening the water tap and always flowing water. At this time, the open / close valve provided in the water meter controls the degree of opening and closing of the flow path by the operation control means, so that dead water for freezing prevention can be reduced to the minimum flow rate without discharging excess water. Can be used. Furthermore, even if it freezes, if the freeze is thawed, a flow rate will be generated, but at that time, it can also be shut off by an on-off valve. Since it is a drive type on-off valve using a stepping motor, the degree of opening and closing can be adjusted freely.
[0017]
Moreover, various means such as the on-off valve, the flow rate measuring means, and the temperature detecting means can be used outdoors even without a power source by adopting a battery drive system. In particular, the ultrasonic flow rate measuring means and the on-off valve used by the water meter can be installed outdoors even when the power source is not nearby by being battery driven.
[0018]
In this way, the flow rate and temperature can be measured from the propagation time of ultrasonic waves without newly installing a temperature sensor. Freezing can be predicted from the temperature change of the temperature detection means, and the time of freezing is predicted, and it is determined whether it is an early morning time zone where the possibility of freezing is high, thereby improving the prediction accuracy Can do. Also, an alarm can be notified to prevent freezing. And when generation | occurrence | production of freezing is estimated, useless water discharge can be reduced by controlling the flow volume of waste water with an opening-and-closing means. Furthermore, by using a battery drive system, it can be used outdoors without a power source.
[0019]
Although the flow rate and temperature were measured using the ultrasonic propagation time, the same effect can be obtained with a mechanical water meter or mechanical gas meter if a temperature sensor is installed to detect the temperature. Is obvious. In addition, by storing storage means to store past data and learning to improve the prediction accuracy from the predictive degree of accuracy, freezing prediction adapts to the environment where each water pipe and water meter are placed. It is also possible to increase the accuracy.
[0020]
Next, a second embodiment will be described with reference to FIG. Parts having the same structure and the same function as those of the first embodiment are denoted by the same reference numerals, detailed description thereof is omitted, and different parts will be mainly described.
[0021]
As shown in FIG. 3, when the temperature detected by the temperature detection unit 14 is equal to or lower than a predetermined temperature, the flow rate correction unit 24 is configured to correct the measured flow rate measured by the flow rate measurement unit 13.
[0022]
According to the above configuration, when the temperature is equal to or lower than the predetermined temperature, the flow rate discharged from a water tap or the like can be corrected to reduce the flow rate in order to prevent freezing. In other words, water departments call for water discharge from water taps as a measure to prevent freezing, but each household may not discharge water if the water discharge rate is collected at the water charge. As a result, a freezing accident occurs and a large damage occurs. However, by measuring the temperature, when there is actually a risk of freezing, the collection of water charges can be reduced by setting the discharge flow rate for freezing prevention to a low flow rate. As a result, the water can be discharged without worrying about the water charge, so that a freezing accident can be prevented.
[0023]
It is also possible to monitor not only the temperature but also the flow rate of the discharged water so that it does not use a large amount of water for reasons of freezing for freezing prevention. The flow rate used is corrected and accumulated at a low flow rate, but if the flow rate exceeds a predetermined flow rate, a prescribed fee can be collected without correction. In addition, the flow rate can be limited by narrowing the flow path with an on-off valve.
[0024]
Furthermore, by managing the time together with the flow rate and temperature with the timekeeping means, the usage flow rate at the predetermined time is corrected, and the nighttime freezing prevention water discharge is corrected for each household by correcting the usage flow rate to a smaller level than the actual flow rate. We can have you cooperate in drainage without burdening water rate.
[0025]
In this way, by correcting the flow rate of the waste water used for freezing prevention to be less than the actual flow rate, the charge burden on the water user can be reduced and the water discharge can be strengthened to reduce freezing accidents. And the charge burden of a water supply user can be reduced by correcting the flow rate of the waste water used for freeze prevention with a low flow rate. In addition, by managing the flow rate and time, it is possible to improve the accuracy of the determination that the waste water is being used.
[0026]
In addition, by notifying the freezing at the same time with the communication means, and notifying the current use flow rate to the management center or the like, it is possible to know where the freezing prevention is not performed even though the freezing is predicted. .
[0027]
Next, a third embodiment will be described with reference to FIG. Parts having the same structure and the same function as those of the first embodiment are denoted by the same reference numerals, detailed description thereof is omitted, and different parts will be mainly described.
[0028]
As shown in FIG. 4, when the temperature detected by the temperature detecting means 14 is within a predetermined temperature range, a measurement control means 25 for stopping the operation of the flow rate detecting means is provided.
[0029]
According to the said structure, the time slot | zone in which freezing generate | occur | produces can be estimated by detecting temperature. The time zone is water discharge for preventing freezing, and if it is determined that there is no need to measure the flow rate and add it to the water bill, it is not necessary to measure the flow rate, so the flow rate measuring means can be stopped. In addition, there is a case where the water flow is frozen at some point, but in this case also, the flow rate detecting means can be stopped without measuring the flow rate. In either case, the power consumption can be reduced by stopping the flow rate measuring means, and the battery life can be extended when battery-driven.
[0030]
It should be noted that the time interval of flow rate measurement can be set longer or shorter depending on the temperature detected by the measurement control means, without stopping completely. Therefore, at low temperatures, if the water is freezing to prevent freezing, the flow rate change is small and the flow rate is small. As a result, power consumption can be suppressed, and the battery life can be extended.
[0031]
【The invention's effect】
As described above, the water meter according to the present invention can predict freezing from the temperature change of the temperature detecting means, correct the detected flow rate, or stop the flow rate measurement, and is inconvenient due to a temperature drop. Can be eliminated.
[Brief description of the drawings]
FIG. 1 is a block diagram of a flow meter showing a first embodiment of the present invention. FIG. 2 is a characteristic diagram showing the operation of the flow meter. FIG. 3 is a block diagram of a flow meter showing a second embodiment of the present invention. FIG. 4 is a block diagram of a flow meter showing a third embodiment of the present invention. FIG. 5 is a block diagram of a conventional flow meter.
DESCRIPTION OF SYMBOLS 9 Flow path 12 Transmission / reception means 13 Flow rate detection means 14 Temperature detection means 15 Freezing prediction means 16 Timing means 17 Notification means 18 On-off valve (open / close means)
19 Operation control means 20 Battery 24 Flow rate correction means 25 Measurement control means

Claims (5)

Transmitting and receiving means for transmitting and receiving sound waves by propagating sound waves in the fluid in the flow path;
Flow rate detecting means for detecting a flow rate from the propagation time of transmission and reception of the sound wave;
Temperature detecting means for detecting the temperature of the fluid from the propagation time of transmission and reception of the sound wave;
A time measuring means for measuring time;
Freezing prediction means for predicting a freezing time from a temporal temperature change of the temperature detecting means ,
An on-off valve that opens and closes the flow path ,
The on-off valve opens the flow path at the freezing time,
When freezing occurs in this time zone, the water flow meter characterized in that the flow rate measurement interval of the flow rate detection means is lengthened or the flow rate measurement is stopped. When freezing prediction time is a range of a predetermined time, water meter of claim 1, further comprising an informing means for informing an alarm. When the detected temperature change of the temperature detecting means reaches a predetermined temperature change, water meter of claim 1, further comprising an informing means for informing an alarm. Any one water meter according to claims 1-3 comprising an operation control means for controlling the switching means by detecting the temperature of said temperature detecting means. The water meter according to any one of claims 1 to 4 , wherein a battery is used as a driving power source.

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