JPS59226825A - Flow rate measuring device - Google Patents

Abstract

PURPOSE:To measure a flow rate per unit time accurately by measuring time intervals of flow rate pulses several times, calculating the mean time interval, and calculating the flow rate per unit time form the mean time interval. CONSTITUTION:The reed switch 2 of a flow rate sensor turns off every time a gas meter 1 measures unit measurement volume, and its state change is sent as flow rate pulses to an arithmetic device 3. The arithmetic device 3 measures the time intervals of flow rate pulses sent from the reed switch 2 through a timer 4, and sends the time intervals to a processor 5. The processor 5 calculates the mean value T of the last time interval stored in a storage device 6 and the current time interval sent from the timer 4, form an equation I. Then, the flow rate Q per unit time is calculated from q/T, where (q) is the unit measurement volume. Thus, the flow rate per unit time is measured accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a flow rate measuring device, and more particularly to a flow rate device that measures the flow rate of a fluid per unit time.

Conventional configuration and its problems For example, a model gas meter has been used to measure the flow rate of conventional fluids (city gas, LP gas, etc.).

This gas meter has four measuring chambers separated by membranes, an interlocking mechanism that transmits the movement of the membrane that moves as the gas flows, and a force transmitted by the interlocking mechanism that allows gas to flow into the measuring chamber. , a gear train that connects the chain mechanism to the indicator, and the indicator, and the indicator indicates the integrated value of the gas flow rate passing through the meter. Naturally, this gas meter cannot measure the flow rate per unit time.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks and aims to measure the flow rate per unit time.

Structure of the Invention In order to achieve the above object, the flow rate measuring device of the present invention includes a flow rate sensor that transmits a flow rate pulse every time a unit flow rate is detected in a gas supply line, and a flow rate pulse from this flow rate sensor as input, and a flow rate measurement device of the present invention. It consists of a calculation device that measures the time interval of pulses multiple times, calculates the average time interval, and calculates the flow rate per unit time a from the average time interval, and can measure the flow rate per unit time. This method has the effect of absorbing measurement variations of flow rate sensors and increasing accuracy compared to a method that calculates the flow rate per unit time from the time interval measurement results of flow rate pulses.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a gas meter provided in a gas supply line, and a magnet is provided on the belly plate of the gas meter 1 or its interlocking mechanism. Reference numeral 2 denotes a magnetic field sensor that detects the presence or absence of displacement of the magnet, and is, for example, a reed switch. That is, the gas meter 1, the magnet, and the reed switch 2 constitute a flow rate sensor. The reed switch 2 is turned from on to off each time the gas meter 1 measures a unit measurement volume, and this change in state is sent to the arithmetic unit 3 as a flow rate pulse.

The arithmetic device has the configuration shown in FIG.

In FIG. 2, the time interval of flow rate pulses sent from the reed switch 2 is measured by a timer 4. That is, the timer 4 measures the time from the first time when the reed switch 2 is turned on from off to the time when the reed switch 2 is turned on from the next time.

The time interval as a result of the measurement is sent to a processing device 5. The processing device 5 calculates the average value of the previous time interval stored in the storage device and the current time interval sent from the timer 4 using the formula below.

Average time interval 〒=Rikuka Zayokuzuimachi iri y 倶煕■ Obtain - From the average time interval T thus obtained and the unit metered volume q of the gas meter, the flow rate Q per unit time is calculated (q /T)
, and output the result as Q. On the other hand, the current measurement value is transferred to the storage device 6 in preparation for the next measurement. For example, the unit measurement volume of a meter is 0.0 for a No. N2 meter.
6M, and if the time interval is 3 seconds both times, the flow rate per unit time is 0.6 Q/3 seconds - 0.2 fl/second. If you want to find more time-dependent flow rate, change this to 3.
, 600 times. For high quality items, 0.2 x 3,600 = 72
0R/hr=0.72yrl/hr.

In this way, according to this embodiment, the flow rate per unit time can be measured, and since the average amount of the two measurement results is calculated, it is possible to absorb measurement variations in each measurement of the flow rate sensor, and to accurately measure the flow rate per unit time. It is possible to obtain the effect of being able to measure the flow rate.

Next, in FIG. 3, the same numbers as in FIGS. 1 and 2 indicate the same things, and what is different from FIG. , is a shift register that stores the fit determination results of timer 4 up to two or more n times ago. The processing device 5 calculates the average value of the measurement results of the timer 4 and all the measurement results up to n times before the shift register 7, that is, (n+1) pieces of data, and calculates the flow rate per unit time from this averaging. At the same time, the current measurement result is sent to the shift register 7. The data used in the calculations are each shifted, and the oldest data (that is, the data used n times before the calculations) is erased in preparation for the next calculation.

According to this embodiment, since more time interval data is used than in the embodiment shown in FIG. 2, measurement variations of the flow rate sensor can be more absorbed, and the flow rate per unit time can be calculated more accurately.

Effects of the Invention As described above, according to the present invention, since the flow rate per unit time is calculated from a plurality of data on the time intervals of flow rate pulses from the flow rate sensor, the following effects can be obtained.

1. Can measure westward flow rate per unit time.

2. Since the average flow rate of multiple data is calculated, variations in flow rate sensors can be absorbed and accurate values can be calculated.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a flow rate measuring device according to an embodiment of the present invention, FIG. 2 is a configuration diagram of the same calculation device, and FIG. 3 is a configuration diagram of a calculation device according to another embodiment. 1... Gas meter, 2... Reed switch, 3... Arithmetic device. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3 Figure 2 Figure 3

Claims (1)

[Claims] A flow rate sensor is provided in the fluid supply line and transmits a flow rate pulse every time a unit flow rate is detected, and the flow rate sensor receives the flow rate pulse as input, measures the time interval of this flow rate pulse, and compares the time interval measured so far with the flow rate sensor. A flow rate measurement device comprising a calculation device that calculates an average value with respect to the current time interval and calculates a flow rate per unit time from this average value.