JPS6227850Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a new metering operation device that enables smooth metering operation and emergency stop.

Conventionally, in the case of a generally known quantitative meter, for example, a constant flow shipping device that can supply a desired set flow rate, the drive pump operation is generally controlled simultaneously in conjunction with an on-off valve for each constant flow rate shipment. I'm letting you do it.

When shipping a fixed amount continuously to several liquid supply tanks, such as tank trucks, etc.,
When operating a driving pump in conjunction with an on-off valve, the pump operation becomes intermittent, which not only shortens the life of the pump but also damages the electrical control, which is not a good idea.

Therefore, this idea was developed to allow the drive pump to continue operating even when the opening/closing valve is closed for a relatively short period of time during tank truck shipments where liquid supply operations are performed several times in succession at relatively short intervals, as described above. ,
The present invention provides a novel intermittent metering device that is characterized by having a delay circuit that can stop pump operation only after a certain period of time, and further provides an emergency stop function in the event of an abnormality so that the device can be opened and closed regardless of the presence of the delay circuit. It is an object of the present invention to provide a metering operation device that can close a valve and stop driving a pump at the same time.

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

Fig. 1 shows a quantitative operation unit, which is equipped with a quantitative setting section 2 that can set the quantitative value of the liquid flowing in the piping (not shown), and which is proportional to the flow rate from the flow meter (not shown) installed in the piping. It is now possible to receive measurement signal A. A valve metering circuit 3 is connected to the metering unit 1 and is capable of receiving a metering start/end signal S, and is connected to a relay circuit S via a NOT circuit 4.

5 is a valve warning circuit which is also connected to the quantitative operation unit 1 and can receive the warning signal M.
It is connected to a relay circuit M via a NOT circuit 6. These two circuits 3 and 5 allow opening and closing valves (not shown) provided at desired locations on the piping to be opened and closed in two stages to flow a desired constant flow rate.

Note that if the opening/closing valve is operated in one step, the valve advance notice circuit 5 can of course be omitted.

Reference numeral 7 denotes a drive circuit for a pump (not shown), which is connected to a relay circuit P via an OR circuit 8 and a NOT circuit 9. The OR circuit 8 is connected so as to conduct the metering start/end signal S from the metering operation unit 1 which is transmitted to the valve metering circuit 3, and also receives the signal from the oscillator 10 to open and close for a desired time even after the valve is closed. A pump timer circuit 11 is connected which can maintain the operation of the pump drive circuit 7.

This pump timer circuit 11 includes a flip-flop circuit 12 and an oscillator 10, for example.
A counter 13 that receives and counts clock pulses transmitted every second or every 10 seconds, a setter 14 that sets the time, and a one-shot multi-circuit MM ₁ that can transmit a one-shot pulse that can set or reset the flip-flop circuit 12. ，
Consists of MM ₃ . Note that 15 is an AND circuit for sending the clock pulse of the oscillator 10 to the counter 13, and 16 is an OR circuit for passing the one-shot pulse from the one-shot multi-circuit _MM3 .

Reference numeral 17 denotes an emergency stop operation circuit connected to the OR circuit 16, which includes an emergency selection circuit 18 for receiving various abnormal signals d and determining the necessity of stopping the pump, a delay circuit 19, and a one-shot multi-circuit _MM2 . and OR for quantitative operation unit 1.
It is configured to transmit an abnormality signal via the circuit 20 to perform an emergency stop of the metering operation.

Incidentally, reference numeral 21 is a power reset signal generating section connected to the OR circuit 16 and resetting the flip-flop 12 when a power supply voltage is applied.

The action will be explained based on the above structure.

First, the quantitative setting section 2 provided in the quantitative operation unit 1
Set the amount of liquid supplied. For example, when supplying liquid to a tank truck, one
After setting the quantity with a dial, etc. to Kl, 2Kl, or 4Kl, press the start button to start dispensing liquid.

Quantification start/end signal S from quantification operation unit 1
is transmitted to the valve metering circuit 3 to open the opening/closing valve one step, and at the same time, a portion of the signal passes through the OR circuit 8 and activates the pump drive circuit 7 to start the liquid supply operation.

By the way, since the opening/closing valve has a two-stage opening/closing structure, the valve warning circuit 5 is activated by the next warning signal M sent from the quantitative operation unit 1, and the opening/closing valve is completely opened and the liquid supply operation proceeds. . In this way, when the liquid supply operation approaches the set amount, the transmission of the warning signal M is first stopped, the valve warning circuit 5 is closed, and the opening/closing valve is closed by one step, and when the fixed amount is reached, the metering start/end signal S When the valve metering circuit 3 is also stopped, the opening/closing valve is completely closed and the liquid supply operation is stopped.

By the way, the first one-shot multi-circuit _MM1 of the pump timer circuit 11 sets the flip-flop circuit 12 by transmitting a one-shot pulse in response to the fall signal of the quantitative start/end signal S.
The pump drive circuit 7 can be kept closed through the OR circuit 8 without opening, and the pump can continue to be driven.

The output signal of the flip-flop circuit 12 is input to an AND circuit 15, and the clock pulse from the oscillator 10 is transmitted to the counter 13, where counting is performed until a preset delay time is reached.
When the set value is reached, a signal is sent to the third one-shot multi-circuit MM ₃ and a one-shot pulse is generated which can reset the flip-flop circuit 12 via the OR circuit 16. By this reset operation, the output signal of the flip-flop circuit 12 is stopped, the operation of the pump drive circuit 7 is stopped, and the drive of the pump for liquid supply is completely stopped only after a certain time delay after the opening/closing valve is closed. That will happen. (Refer to the time chart in Fig. 2 above.) Therefore, within the delay time set by this pump timer circuit 11, the first hatch is sequentially transferred from the first hatch to the second hatch, and the second hatch is If the liquid supply operation is continued intermittently from the first hatch to the third hatch, the pump can perform intermittent liquid supply while the pump is in the driving state.

By the way, if an abnormal situation or an emergency situation occurs during the liquid supply operation, this abnormality signal d is transmitted to the quantitative operation unit 1 to stop its operation, and is also transmitted to the emergency stop operation circuit 17 and is transmitted to the emergency level selection circuit 18. After determining whether it is necessary to stop the pump, its output is input to the delay circuit 19, and after a slight time delay (T) set by the delay circuit 19, it is input to the second one-shot multi MM ₂ , and a one-shot pulse is generated. be done.

By the way, prior to the transmission of this one-shot pulse, when the transmission of the quantitative start/end signal S and the notice signal M is urgently stopped due to the emergency operation stop of the quantitative operation unit 1, the first one-shot multi-circuit is activated by the falling signal. MM ₁ works and a one-shot pulse is transmitted to maintain the flip-flop circuit 12 in the set state as described above.
As mentioned above, the one-shot pulse in an emergency is transmitted immediately after that and resets the flip-flop circuit 12 via the OR circuit 16, so the pump drive circuit 7 that drives the pump is opened urgently and the liquid supply is stopped. can be stopped. (Refer to the graph on the left side of the time chart in Figure 3 for emergencies.) Next, when the emergency situation disappears and the normal state returns, the alarm signal will be stopped, so by inputting the start signal, the fixed amount opening/closing of the opening/closing valve will be completed. The signal S and the warning signal M are simultaneously transmitted and the liquid supply operation is restarted. (Refer to the graph on the right side of the time chart in Figure 3 when restart is normal.) In this way, the same quantitative liquid supply operation as described above is performed.

According to this invention, when fluid is supplied continuously intermittently, the pump is constantly delayed without having to repeatedly operate and stop the pump in connection with the opening and closing operations of the on-off valve each time the fluid is supplied. Since the pump is operated within the specified time, the service life of the pump can be significantly improved and failures can be reduced. In addition, in the event of an emergency, the pump can be stopped without delay, ensuring safety. .

Further, according to this invention, since the emergency stop operation circuit is simply incorporated into the delay circuit for controlling the operation of the pump, the construction is simple.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the metering operation device according to the invention, FIG. 2 is a time chart of the device in normal operation, and FIG. 3 is a time chart in an emergency situation. DESCRIPTION OF SYMBOLS 1...Quantitative operation unit, 3...Valve quantitative circuit, 5...Valve warning circuit, 7...Pump drive circuit, 11...Delay circuit, 12...Flip-flop circuit, 17...Emergency stop operation circuit.

Claims (1)

[Scope of utility model registration request] In a metering device that receives a flow rate signal transmitted from a flowmeter as input, sets a desired amount of liquid to be supplied, and is capable of supplying a fixed amount of liquid via a metering operation unit that issues operating commands for a pump and an opening/closing valve, and the liquid supply element. During normal operation, the pump is driven by the first one-shot multi-circuit, which is activated by the falling signal at the completion of liquid supply of the metering signal that controls the on-off valve, and the flip-flop circuit output signal, which is set by the one-shot multi-circuit output. At the same time, the pump drive is stopped by starting the time counter and resetting the flip-flop circuit after a desired set delay time, and when an abnormality occurs, an abnormality detection signal is input as a stop signal to the metering operation unit, and the pump drive is stopped. A delay time is given so that the second one-shot multi-circuit output is output after the first one-shot multi-circuit output, and the flip-flop circuit is reset by the second one-shot multi-circuit output, thereby causing an emergency stop of the pump. quantitative operation circuit.