JPS59108112A - Controlling device of shipment of constant quantity - Google Patents

Abstract

PURPOSE:To ship a fluid in a constant quantity precisely by sampling a flow rate integration counter and a constant quantity setter periodically, presetting the remaining value of shipment in a preset counter and fully closing a shipment controlling valve when the preset counter is turned to zero. CONSTITUTION:A flow rate oscillator FS and a control valve MV are arranged on a shipment pipe line P of a fluid and pulse-like flow rate signals from the FS are integrated by an integrating counter ACT. The preset counter PCT subtracts the flow rate signal from a preset value. A computer MCP samples the counted value of the integrating counter ACT and a constant quantity setting value CSV to find out the remaining value of shipment from the operation of the CSV and the counted value of the ACT. When the remaining value is less than the maximum preset value of PCT, the remaining value is preset on the PCT, and when the remaining value is turned to ''0'', the control valve MV is fully closed to complete the shipment. Consequently, the quantity of shipment can be precisely secured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a quantitative shipping control device that controls shipping only a predetermined amount of fluid such as fuel or chemicals.

Such devices monitor the flow rate of fluid using a flow meter, and when the cumulative flow rate reaches a fixed value, fully close the shipping control valve and automatically carry out fixed-quantity shipment. , a fixed period scanning method, or a preset counter method are generally used.

In other words, in the fixed-period scan/interval method, it is monitored whether the shipping amount has reached a fixed value at every fixed sampling period, and when the shipping amount exceeds the fixed value, shipping is considered complete. In the preset counter method, a preset counter with a maximum preset value corresponding to the quantitative value is prepared, and the quantitative value is preset and subtracted according to the shipment amount, and when the count value reaches zero, the shipment is considered complete. There is.

However, in the fixed-period scanning method, in order to control the shipment amount with high precision, sampling must be performed at short intervals, which requires high-speed calculation processing for control, and the processing load is extremely high. This results in increasing drawbacks.

In the preset counter method, if the quantitative value is small or if the amount of shipment is to be controlled with high resolution, an extremely large-capacity preset counter is required, making the device expensive and Even if temperature compensation is performed for the shipment amount, there are drawbacks such as the fact that the result cannot be reflected in the count value of the preset counter.

The present invention has the purpose of fundamentally eliminating such drawbacks of the conventional art.1. The flow rate signal from the flow rate transmitter is inputted by an integration counter, and the count value of the counter and the quantitative setting value that determines the shipping amount are sampled at regular intervals,
And each time, based on these, calculate the remaining amount value for shipping, preset this remaining amount value to a preset counter, and subtract from the preset value using the flow rate signal,
The present invention provides an extremely effective 'jJl quantity shipping control device that completely closes a shipping control valve in immediate response to an interrupt signal sent out when the count value of a preset counter becomes zero.

Hereinafter, the present invention will be explained in detail with reference to figures showing examples.

FIG. 1 is a functional block diagram showing the configuration, and the fluid shipping pipeline includes a flow transmitter FS of a flow meter and
When the control valve Δ4V such as a motor valve is set to -C, a pulse-like flow rate signal is sent from the flow rate transmitter FS according to the flow rate of the fluid, and is multiplied by the totalizing counter ACT, while at the preset counter PCT. The flow rate signal is subtracted from the preset value.

In addition, the computer ΔffcP, which consists of a microprocessor, memory, input/output circuit, etc., is provided with a quantitative setting value CSV that determines the amount of shipment, a fixed-cycle program CCP, and an interrupt program rNP. The count value of the integration counter ACT and the fixed quantity set value C8V are sampled by the above execution, and the remaining quantity value for shipping is determined by the calculation of (fixed quantity set value) - (count value), and this is the maximum preset value of the preset counter PCT. When the value is below the preset counter PCT
When the remaining amount value becomes zero, K controls the control valve MV and completely closes it to complete shipping.

Note that when the count value of the preset counter PCT becomes zero, an interrupt signal is sent, and the interrupt program INF is executed immediately in response to the interrupt signal.
V is controlled to be fully closed.

Figure 2 is a flowchart of the fixed-cycle program CCP, which reads the count value of the integration counter CT and then performs correction calculations on the count value according to the type and temperature of the fluid. After calculating the shipping amount, store the count value after the correction calculation, and calculate the remaining amount of shipment by the above calculation. If the result is ``remaining amount = 0'', control is executed. Perform "fully closed control" of valve "MY".

Also, if 1 remaining amount; 0'' is No, perform a ``reverse correction calculation on the remaining amount'' to find the remaining amount and the corresponding count value, and then determine the ``remaining amount minus maximum preset value''. This is Y
If es, the remaining amount is preset to the preset counter @PCT, and the above operation is repeated according to the sampling period.

Therefore, a determination is made as to "remaining amount - ○" every time sampling is performed, and if "remaining amount - ○" is Yes, the control valve MV
is fully closed and shipping is complete, while "Remaining amount - 0"
While is No, the presetting of the remaining amount for the preset counter PCT is repeated on the premise that the remaining amount is less than the maximum preset value of the preset counter PCT.

FIG. 3 is a timing chart showing the operating status of FIG. is stored as data brn indicating the shipped amount, while the remaining amount data Rm obtained by "calculating remaining amount" in Fig. 2 is gradually decreasing until it becomes less than the maximum preset value MPV of the preset counter PCT. For example, data Rrn is preset PST to preset counter PCT.

In addition, the count value (C) of the preset counter PCT is subtracted by the meteor signal and gradually decreases, and when this reaches zero, an interrupt signal (d) is sent, and the control signal (e) is accordingly As soon as it is sent out, the control valve MV becomes fully closed.

Therefore, the count value (b) is read as data bm in response to the sampling signal (a), and before this becomes equal to the quantitative setting value CSV and it is determined that "remaining amount - o" has become Yes. However, as soon as the count value of the preset counter PCT becomes zero, the control valve 711v becomes fully closed, so that the shipment amount is maintained accurately.

In addition, the preset counter PCT contains the remaining amount data Rm
Since it is preset after MPV becomes equal to or less than the maximum preset value MPV, a counter with a small capacity can be used without requiring a counting capacity corresponding to the total shipment amount.

Note that since the result of performing the "inverse correction calculation on the remaining amount" is preset in the preset counter PCT, the count value indicating the remaining amount is accurate and a highly accurate shipment amount can be ensured.

Since the preset counter PCT is repeatedly preset, it becomes possible to change the quantitative setting value during shipment, and also to adjust the preset value according to temperature changes by "reverse correction calculation for the remaining amount". As long as the information is updated, the amount shipped will be accurate even if temperature changes occur during shipping.

However, in Figure 2, the preset counter "PCT"
Various modifications are possible, such as ``presetting the remaining amount'' only once, or omitting the ``correction calculation'' step if high precision is not required.

As is clear from the above description, according to the present invention, the counting capacity of the preset counter is reduced and the shipping amount is regulated by the preset counter.
It becomes possible to make the sampling period by a fixed-period program a long period, the action load on the computer is reduced, the cost of the device can be easily reduced, and a remarkable effect can be obtained in quantitative shipment control of various fluids.

[BRIEF DESCRIPTION OF THE DRAWINGS] The figures show an embodiment of the present invention, in which FIG. 1 is a functional block diagram, FIG. 2 is a flowchart of a periodic program, and FIG.
The figure is a timing chart showing the operating status of FIG. 1. FS...Flow rate transmitter, Mv...Control valve, A
CT--Integration counter, PCT--Preset counter, MCP--Electronic machine, C8v--Quantitative setting value, CCP--Regular cycle program, INF--
...Interrupt program. Patent Applicant: Yamani / Newel Co., Ltd. Agent: Masaki Yamakawa (and 1 other person) Ki 1 is 1 P Figure 3 Chin 2 Ko

Claims (3)

[Claims] (1) An integration counter that integrates the flow rate signal from the flow rate transmitter, and the count value of the counter and the quantitative setting value that determines the shipping amount are sampled at regular intervals, and each time the count value and the quantitative setting value are used for shipment. a preset counter that subtracts the flow rate signal from the preset value and sends an interrupt signal when the count value becomes zero, and presets the remaining value to the counter. 1. A quantitative shipping control device comprising: presetting means for fully closing a shipping control valve in immediate response to the interrupt signal. (2) The quantitative determination according to claim 1, characterized in that a calculation means is used to calculate the remaining amount value for shipment in addition to performing a correction calculation for temperature compensation on the count value of the integration counter. Shipping control device. (3) The fixed quantity shipping control device according to claim 1, further comprising a presetting means for presetting a remaining amount value for shipping to a preset counter in accordance with sampling at regular intervals.