JPS6395320A - Apparatus for detecting flow rate of combustible liquid - Google Patents

Abstract

PURPOSE:To secure an explosion-proof property and to accurately detect a flow rate, by detecting the flow speed of the combustible liquid sent in a transport pipe under pressure by a rotary body and converting the detection value to an air signal by an air interrupter. CONSTITUTION:A flowmeter 14 is provided to a combustible liquid transport pipe 9 and has a rotary body 5 rotating corresponding to the combustible liquid sent under pressure. An air interrupter 25 has the slit plate 18 connected to the rotary shaft 16 of the rotary body 15 and compressed air is always injected to said disk 18 from a jet orifice 34 to form an intermittent air signal. A count part 27 counts a flow rate on the basis of the intermittent air signal formed by the air interrupter 25. By this method, an electric spark source can be perfectly removed and the load to the rotary body 15 is reduced and resolving power per revolution of the rotary body is enhanced and, as a result, a flow rate can be detected with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a flow rate detection device in a combustible liquid transport device. That is, the present invention relates to a flow rate detection device in a transportation device that pumps flammable liquids such as crude oil, aviation fuel, and liquid chemical products through a transportation pipe.

``Prior Art'' Flowmeters attached to equipment for transporting flammable liquids, such as crude oil, aviation fuel, and certain liquid chemical products, which form flammable mixtures even at low temperatures, have a total A high level of explosion protection is required to prevent any spark from igniting.

Therefore, the following types of flow rate detection devices have been used in conventional flammable liquid transport devices of this type.

In other words, the detection container has a rotating body that rotates in response to the flow rate of the flammable liquid pumped through the oil supply pipe, and the flow opening is determined by the constant volume and rotational speed generated between the detection container and the rotating body. Positive displacement flowmeters were commonly used to measure An integrating gear mechanism is connected to the rotating shaft of the rotating body.
The flow rate was integrated mechanically. Also, a shaft encoder such as a photocoupler was connected to this rotating shaft to convert it into an electrical pulse signal.

``Problems that Ming is trying to solve'' By the way, in such conventional flow rate detection devices,
The following problems were pointed out.

First, flowmeters that mechanically integrate the flow layer have excellent explosion-proof properties, but they have the problem of requiring secondary conversion for remote indication.

Next, a device that converts the rotation of a rotating body into an electrical pulse signal is suitable for remote instructions, but requires a power source for detection, and requires a strictly explosion-proof unit to transmit the detection result as an electrical signal. This explosion-proof unit prevents the rotation of the rotating body, resulting in a lack of accuracy, and the risk of electrical sparks still cannot be completely eliminated.
There was a problem.

In the conventional example, the above-mentioned problems have been pointed out.

In view of the above-mentioned circumstances, the present invention has been made to solve the problems of the conventional methods described above.The present invention detects the flow velocity of the flammable liquid being pumped through the transport pipe using a rotating body, and uses this detected value to It is converted into an intermittent air signal by an air interrupter,
To propose a flow rate detection device that completely eliminates the source of electric sparks by counting this, thereby ensuring explosion-proof properties, and that can accurately detect flow rates and that can provide remote instructions without performing secondary conversion. With the goal.

"Means for Solving the Problems" The technical means of the present invention to achieve this objective are as follows.

This flow rate detection device is used in a transportation device that pumps a flammable liquid through a transportation pipe.

This flow rate detection device has the following means.

The rotating body is attached to the transport pipe and rotates in response to the flammable liquid being pumped.

The slit disk is connected to the rotating shaft of the rotating body and rotates in response to the flammable liquid being pumped.

The air interrupter continuously injects compressed air from a pneumatic source toward the slit disk, producing an intermittent air signal.

The counting section counts the flow rate based on intermittent air signals generated by the air interrupter.

"Function" Since the flammable liquid flow rate detection device according to the present invention is comprised of such means, it functions as follows.

The transport device transports the flammable liquid from a source tank to a destination tank by force-feeding the flammable liquid with a transport pump via a transport pipe.

Therefore, the rotating body attached to this transport pipe rotates in response to the flammable liquid being pumped, and therefore the slit disk connected to the rotating shaft of this rotating body rotates in response to the flow rate. do.

On the other hand, an air interrupter generates an intermittent air signal by constantly injecting compressed air from its injection port and receiving air from its receiving holes through the slits of a rotating slit plate.

Next, the counting unit counts the flow rate of the combustible liquid based on the number of intermittent air flows corresponding to the flow rate included in the intermittent air signal generated by the air interrupter.

In this way, the electric spark source is completely eliminated, the load on the rotating body is reduced, the resolution per rotation of the rotating body is increased, and highly accurate flow rate detection is realized. .

"Embodiments" The present invention will be described in detail below based on embodiments shown in the drawings.

First, we will outline the overall configuration of an aviation fuel tanker, which is a flammable liquid transportation device.

FIG. 1 is a block diagram of the configuration of an aviation fuel refueling vehicle and its flow rate detection device, and FIG. 3 is a perspective view showing its usage state.

In both figures, reference numeral 1 is an aviation fuel refueling vehicle that is a transport device for flammable liquids, and the aviation fuel loaded in a source tank 3 mounted on a chassis 2 of the refueling vehicle 1 is transported to the aircraft via a transportation hose 4. The fuel is transported from the fuel intake port 6 of the aircraft 5 to the destination tank 7, which is the fuel tank of the aircraft 5.

In this state, the aviation fuel, which is a flammable liquid, is transported from the refueling truck 1, which is a transportation device, to the aircraft 5.

A transport pipe 9 is connected to a bottom valve 8 provided at the bottom of a source tank 3 mounted on a chassis 2 of a refueling vehicle 1, and a line strainer 10 and a transport pump 11 are attached thereto. Furthermore, the transport pipe 9 has a filter 12. downstream of the transport pump 11. Pressure control valve 13. A flow meter 14 is provided,
It is connected to the transport hose 4. In this way, a transport conduit is formed between the transport source tank 3 and the fuel tank 7 of the aircraft 5, which is the transport destination tank.

Note that the flow meter 14 has a rotating body 15 that rotates in accordance with the flow rate of aviation fuel, and a rotating shaft 16 of this rotating body 15 is connected to a slit disk 18 of a flow rate detection device 17, which will be described later.
is connected to.

On the other hand, the compressed air supplied from the air pressure source 19 is
A pressure reducing valve 21 that reduces the air pressure to a constant level via the main air pressure pipe 20. The air is input to a pressure control valve 23 that roughly reduces air pressure and maintains it at a constant pressure via a pneumatic filter 22 that removes minute foreign matter and moisture from the air. For example, 0.2KI is controlled by this pressure control valve 23.
The low-pressure air whose pressure has been reduced to about /ci is input to the flow rate detection device 17 via a flexible tube 24 made of a rubber hose or the like.

The flow rate detection device 17 includes an air interrupter 25° amplifying section 2
6. It consists of a counting section 27, and the output of this counting section 27 is
The signal is inputted to the operating section 29 via the flexible tube 28.

The compressed air supplied from the air pressure source 19 described above is passed through the main air pressure pipe 20 to the amplifying section 26 and the counting section 2.
7 and the operation unit 29.

The above is the overall configuration of the aviation fuel refueling vehicle 1, which is a flammable liquid transportation device, and its flow rate detection device 17.

Next, the flow rate detection device 17 will be explained in more detail.

First, the main parts will be explained with reference to FIG.

The rotating body 15 is, for example, a rotating cup of the positive displacement flowmeter 14, which has a rotating body inside. This rotating body 15 is
It is fixed to one end of the rotating shaft 16 and rotates in response to the flow rate of aviation fuel.

Note that instead of the rotating body provided in the existing flowmeter shown in the figure, it is possible to use a rotary body in the form of a rotary plate, one impeller, or a propeller, depending on the viscosity of the flammable liquid, etc. It is possible.

The rotating shaft 16 is held by a bearing 30 attached to the flow meter 14, and the round end of the rotating shaft 16 is connected to a universal joint 31.
．． Bearing 3 provided in main body 32 of air interrupter 25
3 to the slit disk 18.

Note that instead of the above-mentioned universal joint 31, the rotation of the rotating shaft 16 may be transmitted to the slit plate 18 by a gear, a belt, or the like.

The slit disk 18 has a rectangular shape n having the same area.
slits 181, 182. ...18 degrees are arranged radially at the same intervals from the center.

Although the number of slits is 8 bits with n=B in the illustrated example, it may be selected as appropriate depending on the counting section 27. As mentioned above, this slit disk 18 is connected to the rotating body 1.
5, and the number of revolutions increases or decreases in response to the flow rate of aviation fuel, which is a flammable liquid.

The air interrupter 25 includes a main body 32 and slits 181 and 182 that rotate in accordance with the rotation of the slit disk 18.
．． ... 181 etc. It consists of an injection port 34 and a receiving hole 35 that are provided opposite to a point on the main body 32 that is the center of the locus of each slit. The injection port 34 is controlled by the pressure control valve 23 as described above, for example, at 0.2 to 3/CI.
Constantly injects low-pressure air that has been reduced in pressure to about i. The injected low-pressure air flow flows through the slit disk 18 and the slit 181°1, which rotates in accordance with the rotation of the slit disk 18.
82,...18. The flow is passed through and blocked by the receiving hole 3.
5 and is input to the amplifying section 26 via the flexible tube 24.

In addition, in the air interrupter that uses low pressure air of about 0.2 kg/ci used in this example, as a result of experiments, it is recommended to set the diameter of the injection port 34 to 1 m and the diameter of the receiving hole 35 to about 3#.・It was effective in forming an air signal with a good falling edge.

Next, the amplification section 26 is formed, for example, by a switching valve, using the intermittent air signal output from the receiving hole 35 as a pilot, and uses the high pressure air supplied from the air pressure source 19 via the main pneumatic pipe 20 to the switching valve. For example, 2KC1
An intermittent air signal 4 which is increased in pressure to approximately /crA is generated and inputted to the counting section 27.

The counting section 27 is formed of, for example, a pneumatic motor that performs stepping rotation based on an intermittent air signal, and an integration gear mechanism is connected to the rotating shaft of this pneumatic motor, and a display disc or the like connected to this gear measures the flow rate. Instruct. Note that, instead of the above-mentioned pneumatic motor, the counting unit 27 uses a plurality of sequence valves that operate according to a predetermined intermittent number of air, and instructs the flow rate by sequentially operating a plurality of pneumatic cylinders. You may.

Roughly speaking, in this embodiment, the counting section 27 is provided with a transportation amount presetting section 36. The preset section 36 employs, for example, a gear mechanism or a nozzle flapper, depending on the configuration of the counting section. As a result, the counting section 2
7 sends a pneumatic termination signal to the operating section 29 via the flexible tube 28 when the transport amount set by the preset section 36 is reached.゛The operation unit 29 is formed by, for example, a switching valve, using the air-based termination signal output from the counting unit 27 as a pilot, and uses the switching valve to control high-pressure air supplied from the air pressure source 19 through the main pneumatic pipe 20. By opening and closing, a termination signal is generated using air with increased pressure, and this signal is used as a driving source to operate the pressure control valves 13 provided in the transport pipes 9.

In this embodiment, the flow rate control valve 13 was operated by an intermittent air signal, but this air signal can be easily transmitted remotely using a rubber hose or the like.
For example, various controls such as printing out transportation status etc. are possible.

The above is the explanation of the configuration. Next, we will discuss the operation etc.

First, a predetermined amount of aviation fuel to be transported is set by the preset unit 36, and transportation of the aviation fuel, which is a flammable liquid, is started.

As the aviation fuel moves, the rotating body 15 rotates, and the slit disk 18 connected to this rotating body 15 also rotates. This slit plate 18 receives compressed air from the injection port 34 through the slits 181, 182, . ...18.
The liquid is constantly injected toward the receiving hole 35 located at the opposite position. Therefore, slits 181, 182
, . . , 18o is blocked by the slit plate 18 and discharged into the atmosphere.

The other slits 181, 182. -18, is received by the receiving hole 35, and an air intermittent signal is generated on the output side of the receiving hole 35.

This intermittent air signal is transmitted to the amplifying section 2 via the deflection tube 24.
6 and input to the counting section 27. The counting unit 27 counts the number of air interruptions and indicates this number. When the transportation progresses and the amount of transportation reaches a predetermined amount set by the preset section 36, the operating section 29 stops the transportation via the pressure control valve 13.

The above is an explanation of the operation, etc.

In this way, according to this embodiment, by adding an air interrupter mechanism to an existing flowmeter, electric spark sources can be eliminated and aviation fuel can be transported safely and accurately with a simple and inexpensive configuration. It becomes possible.

In addition, in the above-mentioned embodiment, the flow rate detection device in an aviation fuel refueling device was described, but the device is not limited to this, for example, a cargo handling device for a crude oil tanker that requires a high degree of explosion-proofness, It is extremely effective as a flow rate detection device for flammable liquids in various transportation devices in chemical plants.

, ``Effects of the Invention'' As explained above, the flammable liquid detection device according to the present invention uses a rotating body to detect the flow velocity of the flammable liquid being pumped through a transport pipe, and converts this detected value into air using an air interrupter. By converting the intermittent signal into an air signal and counting it, the electric spark source can be completely eliminated, explosion-proofing can be ensured, and the flow rate can be detected accurately.

In this way, the present invention has excellent explosion-proof properties and accuracy, and allows for remote instructions without performing secondary conversion, eliminating the problems that existed in conventional examples of this type. The effects are significant and significant.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an aviation fuel refueling vehicle and its flow rate detection device showing an embodiment of the present invention, Figs. FIG. 2 is a perspective view showing the vehicle in use. 1... Refueling truck (transport device) 9... Transport pipe 14... Flow meter 15... Rotating body 16... Rotating shaft 17... Flow rate detection device 18... Slit disk 19. ... Air pressure source 25 ... Air interrupter 27 ... Counting section Fig. 1 Fig. 2

Claims (1)

[Claims] A flow rate detection device for a transport device that pumps a flammable liquid through a transport pipe, comprising a rotating body attached to the transport pipe and rotating in response to the combustible liquid being pumped. a slit disk connected to the rotating shaft of the rotating body; an air interrupter that constantly injects compressed air to the slit disk by an air pressure source to generate an intermittent air signal; and generation of the air interrupter. 1. A flow rate detection device for a flammable liquid, comprising: a counter that counts the flow rate based on intermittent air signals.