JPH0343565B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a liquid supply device.

In order to create a high-speed type of liquid supply device (for example, a gasoline metering machine) (one that can supply a large amount of fuel per unit time), it is necessary to use a flowmeter with higher capacity than the standard flowmeter installed in the standard specification fueling machine. I need. However, since it is undesirable to specially manufacture flowmeters with different specifications in terms of manufacturing costs and management, it is desirable to increase the capacity by combining a plurality of flowmeters with standard specifications.

The present invention is designed to easily detect a failure or abnormality in a measurement system including a flowmeter, a transmitter, or a counting circuit in a liquid supply device equipped with a plurality of flowmeters of the same capacity. This is what I did.

Examples will be explained in detail with reference to the drawings.

1 is an oil pumping pipe, and below is an underground tank (not shown)
The upper end is divided into two branch pipes 2a and 2b. 3 is a fuel pump inserted into the pumping pipe 1, 4 is a pump motor, and 5a and 5b are branch pipes 2, respectively.
first and second flowmeters inserted in a, 2b;
6a and 6b are flow rate pulses (for example, 1/100 liter) according to the measured values of flowmeters 5a and 5b, respectively.
Pulse) The first and second flow rate pulse transmitters transmit Ba and Bb, and 7 is a communication pipe that connects the primary side of the flow meter 5a of the branch pipe 2a and the secondary side of the flow meter 5b of the branch pipe 2b. Va, Vb, and Vc are each branch pipe 2
a, 2b and a valve inserted into the connecting pipe 7.

The branch pipes 2a and 2b are combined to form an oil supply pipe 8, which is connected to a known oil supply nozzle (not shown) via a hose (not shown).

Reference numeral 9 denotes a nozzle detection switch, which is disposed, for example, in a nozzle case provided in the housing of a ground-mounted refueling machine, and is operated by hooking and removing the nozzle to and from the nozzle case. When the nozzle is removed from the nozzle case, the signal from the nozzle detection switch (nozzle signal) rises (H), and when the nozzle is returned to the nozzle case, the nozzle signal falls (L).
).

The nozzle signal H causes the motor control circuit 10 to energize the pump motor 4, and resets the first and second counting circuits 11a, 11b, the addition circuit 12, and the comparison circuit 13. Nozzle signal L causes motor control circuit 10 to de-energize motor 4.

Normally, valves Va and Vb are open and valve Vc is closed. When the nozzle is removed from the nozzle case and the nozzle tip is inserted into the tank to be refueled to refuel, pulse transmitters 6a and 6b emit signals as refueling progresses. The flow rate pulses are counted by counting circuits 11a and 11b. The count output signals Ca and Cb are added in an adder circuit 12, and the signal D representing the addition result (refueling amount) is inputted to the display drive circuit 15 via the switching circuit 14, and the refueling amount (and refueling amount if necessary) is inputted to the display drive circuit 15. Display 16
will be displayed. At this time, the switching circuit 14 is set to guide the signal D from the adding circuit 12 to the display drive circuit 15 by means of the switching switch 17.

Counting output signals Ca of counting circuits 11a and 11b,
Cb is also input to the comparison circuit 13 and the switching circuit 14. Comparison circuit 13 compares both signals Ca and Cb at all times or at regular intervals, and when there is a difference of more than a certain value between the two, it outputs abnormality detection signal E and causes alarm drive circuit 18 to cause alarm 19 to perform an alarm operation. .

The comparison by the comparator circuit 13 can be performed, for example, by using the signal Ca as a reference and determining the ratio or difference between the signal Ca and the signal Cb. For example, each time the signal Ca reaches a certain value (for example, every 1 liter), the difference between the two signals Ca and Cb is determined.

The abnormality detection signal E is also input to the motor control circuit 10 to stop the motor 4.

Then, return the nozzle to the nozzle case, and
Close Vb and open Vc to connect the flowmeters 5a and 5b in series via the connecting pipe 7, and switch the switching circuit 14 by the switching switch 17, for example, the counting circuit 11.
The output Ca of a is guided to the display drive circuit 15, and the nozzle is removed from the nozzle case and the counting circuit 1
1a and 11b are brought back to zero, and a certain amount of oil is supplied by operating the nozzle. This amount of oil is determined by the switch 1 above.
4 is displayed on the display 16 as a measured value by the flowmeter 5a.

The above-mentioned fixed amount of oil supply is supposed to be measured as the same amount of oil supply by the flow meter 5b connected in series with the flow meter 5a. Therefore, the changeover switch 17
is switched, the count output signal Cb of the counting circuit 11b is guided to the display drive circuit 15, and the measured value of the flowmeter 5b is displayed on the display 16.

Note that when the changeover switch 17 is operated so that the signals Ca and Cb are alternatively input to the display drive circuit 15 via the changeover circuit 14, the changeover switch 17 is
The comparison circuit 13 does not perform a comparison operation due to the signal F from.

If there is a difference greater than the allowable value between the previous displayed value (the measured value of the flowmeter 5a) and the current displayed value (the measured value of the flowmeter 5b), either one of the measurement systems (flowmeter,
It is determined that there is a failure or abnormality in the flow rate pulse transmitter, counting circuit, etc.). Therefore, it is possible to detect which system has an abnormality by comparing the measured value from the reference measurement cell with the measured value on the display 16 for each system.

On the other hand, if a large difference occurs between the two display values when connected in parallel but no difference occurs when connected in series, it can be seen that the pipe line containing one of the flowmeters is clogged and the flow is obstructed.

In the above embodiment, only two flowmeters, that is, two measurement systems are provided, but three or more flowmeters may be provided. In this case, the comparison circuit 13 may be configured to use any one system as a reference and compare the measured values of that system simultaneously or sequentially with the measured values of other systems.

As described above, according to the present invention, it is possible to obtain a liquid supply device that has a plurality of measurement systems having the same capacity and can easily detect abnormalities in each measurement system.

[Brief explanation of drawings]

The figure is a block diagram showing one embodiment of the present invention. 1... Pump, 2... Pump motor, 5a, 5
b...Flowmeter, 6a, 6b...Flow rate pulse transmitter, 9...Nozzle detection switch, 10...Motor control circuit, 11a, 11b...Counting circuit, 12...
... Addition circuit, 13 ... Comparison circuit, 14 ... Switching circuit, 15 ... Display drive circuit, 16 ... Display,
17... Selector switch, 18... Alarm drive circuit, 19... Alarm.

Claims (1)

[Scope of Claims] 1. A plurality of flow meters having the same capacity, a liquid supply pipe connecting the flow meters to the liquid supply nozzle, and a connection between the flow meters and the liquid supply nozzle in parallel and in series. a switching valve inserted in the liquid supply pipe for switching between the two connections; a transmitter that transmits a number of flow pulses corresponding to the measured liquid volume of each of the flowmeters; display means for displaying the counted value of the flow rate pulses from the device as at least the amount of liquid to be supplied; and when the flowmeter is connected to the liquid supply nozzle in parallel, the flow rate pulses from each of the pulse transmitters are added together; means for providing a signal to the display means; means for comparing the flow rate pulses from each of the pulse generators and generating a corresponding signal when the ratio or difference exceeds a certain value; means for providing the count value of the flow rate pulses from the pulse transmitters to the display means for each pulse transmitter when the connection of the pulse transmitters is in series.