JPS5838725B2 - flow rate measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flow rate measuring device that allows one counter to integrate flow rate signals from two flow rate detection sections.

For example, when measuring water usage in a remote location,
Usually, a method is adopted in which a flow rate detection section that sends an output signal corresponding to the flow rate used is installed near the flow path, and the output signal sent from this flow rate detection section is integrated by a counter installed at a remote location. There is.

By the way, if the amount of water used fluctuates on the order of several digits depending on the time or season, it is difficult to measure this using a single flow rate detector because there is a limit to the measurement range of the flow rate detector. Therefore, only measurements with large errors can be performed.

For this reason, in such a case, a first flow path capable of passing a large flow rate and a second flow path for a small flow rate are usually provided in parallel with the first flow path. 1. The first and second flow rate detectors are provided with a measurement range that is suitable for the flow rate that can flow through the second flow path, and the flow path is automatically switched with a valve according to the flow rate used. A method is adopted in which the total usage amount is determined by adding the indicated value of a counter that counts the output signal of the first flow rate detection section and the indicated value of the counter that counts the output signal of the second flow rate detection section.

That is, FIG. 1 shows the above-mentioned measurement system, where A indicates, for example, a water supply pipe, 1 is a main flow path for large flow connected in series with the water supply pipe A, and this main flow channel 1 A branch channel 2, which is a pipe thinner than the main channel, is connected in parallel with the main channel, and each of these channels 1.2 is equipped with a flow rate detection section 3, 4 having a measuring range corresponding to its flow rate. An automatic valve 5 that can be opened and closed is provided at the branch point entrance of the path 1.

When the valve 5 is open, that is, when the flow rate is high, the flow rate signals from each of the flow rate detection sections 3.4 are sent to the counters 6.4 provided corresponding to these flow rate detection sections.
By inputting and counting data into 7, the flow rate of water passing through the main flow path 1 and the branch flow path 2 is integrated.

However, with the method described above, when calculating the total flow rate, it is necessary to add up the counts of each counter 6.7, which is extremely troublesome when performing meter reading.
Furthermore, there are various problems such as the possibility of obtaining an incorrect total value.

This invention has been made in view of the above points, and it is possible to cumulatively add the flow rate signals from two flow rate detection parts with one counter, thereby facilitating meter reading, and making it possible to add up the flow rate signals from two flow rate detection parts by one counter.
Therefore, it is an object of the present invention to provide a flow rate measuring device that can be made smaller, lighter, and lower in cost.

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

In FIG. 2, numerals 3 and 4 are flow rate detection sections similar to those shown in FIG. 1, and these flow rate detection sections 3 and 4 have a measurement range depending on the flow path in which they are installed.

Therefore, in this embodiment, a flow rate detection section 4 whose measurement range is smaller than that of the flow rate detection section 3 is used.

The flow rate detection units 3 and 4 generate on/off signals with a period inversely proportional to the flow rate using transmitters 9 and 10, respectively, and send these on/off signals to the CR charging/discharging circuit 13 via input protection circuits 11 and 12, respectively. .14, the charge stored in the capacitor (not shown) of this CR charging/discharging circuit 13.14 is discharged using the ON signal, thereby sending out a pulse train with a period inversely proportional to each flow rate. It is composed of

The pulse signals sent out from the CR charging/discharging circuit 1314 are respectively input to frequency dividing circuits 15 and 16, where they are frequency-divided and sent in different units from the flow rate detectors 3 and 4 having different measuring ranges. The flow rate signal is converted into a signal of the same unit.

The output of this frequency dividing circuit 15 and 16 is the one-shot circuit 1
7.18, each becomes a signal with a predetermined pulse width that is different from each other, and is supplied as a set signal to flip-flop circuits 19 and 20 (hereinafter referred to as FF circuits 19 and 20) and temporarily stored. be done.

The contents stored in the FF circuits 19 and 20 are supplied to an OR circuit 27 through gate circuits 21 and 22, and one-shot circuits 23 and 24 and 25 and 26, respectively. .

By the way, the gate circuits 21 and 22 have two F-F
When a flow rate signal is not stored in both circuits 19 and 20, both are in an open state, and when a flow rate signal is input to either one of the F-F circuits, the F-F circuit that was input earlier is
The output of the circuit forces the gate of the gate circuit connected to the other FF circuit to close.

For example, when a flow rate signal is supplied to the F-F circuit 19,
The output of the FF circuit 19 causes an operation to forcibly close the gate of the gate circuit 22.

However, if a flow rate signal is supplied to the FF circuit 20 in this state, the flow rate signal is stored in the FF circuit 20.

The signal that has passed through the OR circuit 27 is inputted to a counting counter 29 through a drive circuit 28, where a count corresponding to the flow rate is made and displayed.

When the flow rate is counted by this counting counter 29, the FF circuit existing in the signal path that outputs this flow rate signal is reset.

This opens the closed gate circuit,
It is possible to receive and accept the following signals.

The timing for resetting the FF circuit is set in advance by a one-shot circuit provided in each signal path.

In this embodiment, the reset signal of the F-F circuit 19 uses the signal of the one-shot circuit 25, and the reset signal of the F-F circuit 20 uses the signal of the one-shot circuit 24.

Next, the operation of the inventive device configured as described above will be explained.

In FIG. 1, for example, if it is assumed that the valve 5 is now in the closed state, water flows through the branch channel 2.

As a result, the transmitter 10 outputs a flow rate signal.

This flow rate signal is converted into a pulse signal by the CR charging/discharging circuit 14, frequency-divided by the frequency dividing circuit 16, and then supplied to the one-shot circuit 18, where it is converted into a signal having a predetermined pulse width, and the F-F is supplied to circuit 20.

By supplying the flow rate signal to this F'-F circuit 20, the gate circuit 21 is forcibly closed, thereby blocking the passage of the flow rate signal from the flow rate detection section 3.

The flow rate signal temporarily stored in the F-F circuit 20 is supplied to the OR circuit 27 by passing through the gate circuit 22 and the one-shot circuit 24, 26, and further supplied to the counting counter 29 via the drive circuit 28. It is counted as a flow rate value.

Then, when the counting operation is completed in the counting counter 29, F
-F circuit 20 is reset by a signal from one-shot circuit 24.

Next, in FIG. 1, when the flow rate increases and the pulp 5 is automatically opened, flow rate signals are simultaneously output from the flow rate detection units 3 and 4, but a one-shot circuit 17 is inserted in each signal path. In step 18, the output pulse width and delay time are set in advance to appropriate widths and lengths, so one flow rate signal will always pass first, and the other signal will pass through F-F as described above. This other flow rate signal is not ignored since it is temporarily stored in the circuit and then passed through.

In the above embodiment, the case where the flow rate of water is measured has been described, but the present invention can also be applied to the case where the flow rate of other fluids other than water is measured.

Furthermore, it goes without saying that the present invention is applicable not only to related channels such as a main channel and a branch channel as in the embodiment, but also to two independent channels.

Further, in the embodiment, an oscillator that generates an on/off signal with a period inversely proportional to the flow rate is used, but an oscillator that sends out a voltage pulse output with a period inversely proportional to the flow rate may also be used.

In this case, the CR charging/discharging circuit can be omitted.

Further, the counter is not limited to the electromagnetic coil type, but may be an electronic type.

Further, an LED or LCD may be used to display the information by pressing a button only when reading a meter.

In addition, the circuit uses low power consumption components and can be used for long-term measurements using battery power.

As described in detail above, according to the present invention, two independent flow rate signals from two flow rate detection sections are cumulatively added by one counter, and when the two flow rate signals arrive at the same time, it is possible to Since the data is temporarily stored and sequentially introduced into the counter, meter reading is made easier because there is only one counter, and the entire device is made smaller, lighter, and less expensive, and the reliability of the integrated value is improved. It is possible to provide a flow rate measuring device that can achieve excellent effects such as improved performance.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining an example of a conventional flow rate measuring method, and FIG. 2 is a block diagram showing an example of a fluid measuring device according to the present invention. 3.4...Flow rate detection section, 19, 20...
-Flip-flop circuit, 21, 22...gate circuit, 29...counter.

Claims (1)

[Claims] 1 First and second flow rate detection units that respectively send out output signals with cycles corresponding to the flow rates of fluid flowing through the first and second channels, and output signals of these first and second flow rate detection units. A counter that is installed in each and totals with a single counting device,
A counter is inserted between this counter and the first and second flow rate detection sections, and when the output signals of the first and second flow rate detection sections arrive at the same time, one of the signals is temporarily stored and the other is used as a counter. 1. A flow rate measuring device comprising: a circuit that causes a counter to sequentially count stored signals after counting.