JPH0966999A - Fluid mass measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable measuring with a high degree of accuracy, in the continuous measuring of mass of fluid such as oil, liquefied gas using a load cell, by providing a specific number of measuring bodies and selectively opening or closing an inlet and an outlet valve of each measuring body to restrain waves of the fluid in a container. SOLUTION: Before measuring, containers 2 (2A-2C) of measuring bodies A-C are filled with fluid to be measured and all inlet valves 4 (4A-4C) and outlet valves 9 (9A-9C) are closed. And for filling fluid into a container, into which fluid is supplied, a nozzle 13 is connected to the container and a drive switch 18 is depressed to drive an inlet pump 6 and an outlet pump 11 by means of a control device 20, and at first, the outlet valve 9A of the body A is opened to fill the fluid in the container 2A into the container from the nozzle 13. At that time, reduction in quantity (charge quantity) of fluid is computed from output of a load cell 1A and the computed value is displayed on a display device 17. And fluid in the containers 2B, 2C is measured in a similar manner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid mass measuring device for continuously measuring the mass of a fluid such as oil or liquefied gas using a load cell.

[0002]

2. Description of the Related Art As disclosed in Japanese Patent Laid-Open No. 57-108717, two containers are provided with a meter and a load cell for measuring the weight of the container, and an inflow pipe for each container is provided with an inflow valve. A fluid mass metering device that connects to the inflow main via the outlet, connects the outflow pipe from each container to the outflow main via the outflow valve, opens and closes each valve in response to the measurement signal of each load cell, and Are known. Since these conventional devices have only two weighing bodies, if the amount of inflow from the inflow pipe and the amount of outflow from the outflow pipe are almost the same, weighing is started immediately after refilling the container, It was difficult to accurately weigh the load cell because the weighing started before the load cell became unstable due to replenishment. In addition, continuous measurement was not possible if the measurement was started after the ripples subsided.

[0003]

Therefore, according to the present invention, even if the inflow amount from the inflow pipe is almost the same as the outflow amount from the outflow pipe,
An object of the present invention is to provide a fluid mass measuring device which can start measuring accurately after the load cell has been metered stably, and can measure continuously.

[0004]

To achieve the above object, in a fluid mass measuring apparatus of the present invention, an inflow pipe connected to an inflow main via an inflow valve and an outflow main via an outflow valve. Three weighing bodies each having a connected outflow pipe, a container connected to the inflow pipe and the outflow pipe, and a load cell for weighing the container, and a control connected to the load cell and the valve of each of the weighing bodies. The control device includes a device for selectively opening and closing the inflow valve and the outflow valve of each metering body and controlling the valve so that one of the metering body outflow valves is always open. The control means and the calculation means for calculating the amount of decrease of the weighing signal of the load cell from opening to closing of the outflow valve and outputting the calculated value to the display are provided.

Further, by connecting the inflow pipe and the outflow pipe airtightly to the container via the flexible pipe, it becomes possible to measure a high-pressure fluid or a highly volatile fluid.
In addition, it is preferable in that unnecessary load on the load cell can be reduced.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a diagram showing an entire fluid mass measuring device according to an embodiment of the present invention, FIG. 2 is a diagram showing a block of a control device, and FIG. 3 is a diagram showing timing.

In FIG. 1, a container 2 (A, B, C) is placed on a load cell 1 (A, B, C) of each weighing body A, B, C.
Is placed. The inflow pipes 3 (A, B, C) of each container 2 (A, B, C) are connected to the inflow main pipe 5 via the inflow valves 4 (A, B, C), and the inflow main pipe 5 flows in. It is connected to the tank 7 via the pump 6. In addition, each container 2 (A,
The outflow pipes 8 (A, B, C) of (B, C) are connected to the outflow valve 9 (A,
B, C) connected to the outflow main 10 via the outflow main 1
0 is connected to the discharge nozzle 13 via the outflow pump 11 and the hose 12. The flow passage is configured such that the amount of oil sent by the inflow pump 6 is slightly larger than the amount of oil sent by the outflow pump 11. And inflow pipe 3 (A, B, C)
The outflow pipe 8 (A, B, C) is connected to the outflow valve 9 (A, B, C) via the flexible pipes 14, 15 respectively, and unnecessary load is applied to the load cell 1 (A, B, C). It does not hang.

In each of the above-mentioned devices, the signal line 1 is connected to the control device 20.
6 is connected and controlled. That is,
The control device 20 includes an inflow valve 4 for each of the weighing bodies A, B, and C.
(A, B, C) and the outflow valve 9 (A, B, C) are not opened at the same time, any of the outflow valve 9 (A,
B, C) valve control means 21 for controlling each valve to open
And a calculating means for obtaining the amount of decrease in the measured value of the load cell 1 (A, B, C) from the time when the outflow valve 9 (A, B, C) is opened to the time when it is closed, and outputting the calculated value to the display unit 17. 22
A pump control means 23 for driving the inflow pump 6 and the outflow pump 11 and a central control means 24 for controlling the respective means 21, 22, 23 are provided. Note that reference numeral 18
Is a drive switch.

Next, the operation will be described with reference to FIG. The state before weighing is the container 2 (A, B of each weighing body A, B, C).
B, C) are filled with the fluid to be measured, and all the inflow valves 4
(A, B, C) and the outflow valve 9 (A, B, C) are closed (Fig. 3A). First, when the nozzle 13 is connected to the supply container and the drive switch 18 is pressed, the previous measured numerical value accumulated in the calculation means 22 of the control device 20 is erased and the display 25 is reset to zero. Then, the pump control means 23 drives the inflow pump 6 and the outflow pump 11, and the valve control means 21 opens the outflow valve 9A of the weighing body A (FIG. 3B). As a result, the fluid in the container 2A is sent by the outflow pump 11 and is filled in the supplied container from the nozzle 13. When the fluid in the container 2A flows out, the amount of decrease in the measurement from the load cell 1A is calculated by the calculation means 22, and the calculated value is displayed on the display unit 17.

In this way, the measurement continues, and the load cell 1
When the inside of the container 2A becomes almost empty due to the signal from A, the outflow valve 9B of the weighing body B is opened (FIG. 3C). As a result, the container 2B is connected to the outflow main pipe 10, the fluid in the container 2B flows together with the fluid in the container 2A, and the flow in the outflow main pipe 10 is not interrupted. And outflow valve 9B
After opening, the outflow valve 9A is closed and the measurement from the container 2A is completed (Fig. 3D).

When the measurement continues in this way and the inside of the container 2B becomes almost empty, the outflow valve 9C of the measuring body C is opened this time, and the fluid in the container 2C flows together with the fluid in the container 2B ( (Fig. 3 f). Then, after the outflow valve 9C is opened, the outflow valve 9B is closed and the measurement from the container 2B is finished (FIG. 3G). Similarly, the measurement from the container 2C and the measurement from the container 2A are repeated next.

On the other hand, after the outflow valve 9A is closed and the metering is completed (FIG. 3D), the inflow valve 4A of the container 2A of the weighing body A is opened, and the fluid in the tank 7 is transferred by the inflow pump 6 to the container 2A.
Are replenished (Fig. 3e). Then, when the container 2A is filled up with a signal from the load cell 1A, the inflow valve 4A is closed and the replenishment is completed (Fig. 3C). Similarly, after the weighing is completed, the containers 2 (A, B) of the weighing bodies B and C are also replenished.

When the metering is completed and the drive switch 18 is turned off, the outflow pump 9 is stopped and the open outflow valve 9 is opened.
Close (A, B, C) (Fig. 3). The inflow valve 4 (A, B, C) of the unfilled container 2 (A, B, C) is opened (Fig. 3), and the inflow pump 6 is filled after filling each container 2 (A, B, C). The operation is stopped, the inflow valves 4 (A, B, C) are closed and all the operations are completed (Fig. 3).

[0014]

As described above, in the fluid mass measuring apparatus of the present invention, three measuring bodies each having a container provided on the load cell are provided, and the inflow pipe to each container is introduced into the inflow main via the inflow valve. A fluid mass measuring device having a controller connected to the outlet pipe from each container to the outlet main via an outlet valve, and connected to each load cell and each valve via a signal line Includes a valve control device that selectively opens and closes the inflow valve and the outflow valve of each metering body, and controls the valves so that one of the outflow valves of the metering bodies is always open, and open the outflow valve. Since the calculation means for obtaining the amount of decrease from the weighing signal of the load cell from the closing time to the closing time and the integration means for integrating the numerical values from the calculation means and outputting the result to the display unit are provided, the inflow amount from the inflow pipe is calculated from the outflow pipe. Even if it is almost the same as the outflow amount of Mari, weighing load cell can initiate metering after stable, can be accurately metered.
Further, even if the weighing is started after the ripple is stopped, the weighing can be continuously performed.

[Brief description of drawings]

FIG. 1 is an overall view of a fluid mass measuring apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram of a fluid mass measuring apparatus according to an embodiment of the present invention.

FIG. 3 is a timing chart diagram of the embodiment of the present invention.

[Explanation of symbols]

 A, B, C ... Measuring body 1A, 1B, 1C ... Load cell 2A, 2B, 2C ... Container 3A, 3B, 3C ... Inflow pipe 4A, 4B, 4C ... Inflow valve 5. ..Inflow main 6 ... inflow pump 7 ... tank 8A, 8B, 8C ... outflow pipe 9A, 9B, 9C ... outflow valve 10 ... outflow main pipe 11 ... outflow pump 12・ ・ ・ Hose 13 ・ ・ ・ Nozzle 14, 15 ・ ・ ・ Flexible pipe 17 ・ ・ ・ Signal line 20 ・ ・ ・ Control device 21 ・ ・ ・ Valve control means 22 ・ ・ ・ Calculation means 23 ・ ・ ・ Pump control means 24 ... Central control means

Claims (2)

[Claims] 1. An inflow pipe connected to an inflow main via an inflow valve, an outflow pipe connected to an outflow main via an outflow valve, a container connected to the inflow pipe and the outflow pipe, and It comprises three weighing bodies each having a load cell for weighing the container, and a control device connected to the load cells and valves of the respective weighing bodies. The control device includes an inflow valve and an outflow valve for each weighing body. A valve control means for selectively opening and closing the valve and controlling the valve so that one of the outflow valves of the weighing body is always open, and the reduction amount of the load cell metering signal from the time when the outflow valve is opened to the time when the outflow valve is closed. And a computing means for computing the computed value and outputting the computed value to a display. 2. The fluid mass measuring apparatus according to claim 1, wherein the inflow pipe and the outflow pipe are airtightly connected to the container via a flexible pipe.