JP2002302200A - Flow rate operation system for tank truck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive flow rate operation system for a tank truck to calculate a flow rate of liquefied gas when it is received and discharged. SOLUTION: The flow rate operation system for a tank truck includes: two liquid level gauges 63 and 64, both being provided at a predetermined pitch for detecting the height of a liquid level in a tank; a thermometer 65 for measuring a temperature of liquefied gas in the tank; and a controlling means 51 for producing an output based on the weight of the liquefied gas, which is obtained by such a method that a volume variation amount of the liquefied gas due to the receiving of or the discharge of it is calculated on the basis of the height of the liquid level measured by the liquid level guages 63 and 64 and also an inclination of the tank, which is obtained from the height of the liquid level measured at the two places, that a liquid specific gravity is calculated on the basis of a temperature of the liquefied gas, which is measured by the thermometer 65, and further that the volume variation amount is multiplied by the liquid specific gravity to calculate the weight of the liquefied gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inexpensive flow rate calculation system for calculating a liquid flow rate (weight) when discharging or receiving a liquid from a tank lorry.

[0002]

2. Description of the Related Art In recent years, for example, in place of supplying a liquefied gas by a gas cylinder, a large-capacity installed bulk storage tank is provided in ordinary households, and the liquefied gas is directly transported to the liquefied gas by a small tank lorry called a bulk lorry. The supply form of filling is beginning to spread. As shown in FIG. 6, such a bulk lorry 10 includes a traveling vehicle 11
A tank 12 is mounted on the undercarriage, and a valve instrument box 13 provided with a fluid device and a hose reel box 14 provided with a discharge hose for discharging liquefied gas to a bulk storage tank are provided. The bulk lorry 10 has a tank 12 connected to a discharge hose of a hose reel box 14 via a liquid feed pump, extends the discharge hose to a bulk storage tank, and supplies the liquefied gas to a bulk storage tank of a general household as a supply destination. Is filled.

Conventionally, when a liquefied gas is supplied from such a bulk lorry 10 to a bulk storage tank, the natural frequency of the liquefied gas charged into the bulk storage tank differs depending on the specific gravity called a Coriolis method in order to measure the flow rate (weight) of the liquefied gas. Was used. In this type of Coriolis mass flow meter, a displacement proportional to a flow rate between an inflow side and an outflow side of a vibrating sensor tube is detected by a pickup, and a mass flow rate is obtained from a phase difference.

[0004]

However, such a conventional Coriolis mass flow meter is very expensive because the LP gas is a special one with a temperature correction because the specific gravity varies depending on the temperature. Was something.
Further, since the liquefied gas is measured through a thin tube, the gas is likely to be generated, and a malfunction or an erroneous display may occur. Furthermore, this Coriolis mass flow meter can be used when discharging the liquefied gas in the tank 12 to a bulk storage tank in a general household, but can be used when receiving a large amount and quickly from the base into the tank 12. Did not.

Accordingly, an object of the present invention is to provide an inexpensive flow rate calculation system for calculating a flow rate (weight) at the time of receiving and discharging a liquefied gas in a tank truck.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to a flow rate calculating system for calculating a receiving weight or a discharging weight of a liquefied gas when the liquefied gas is received or discharged by a tank lorry. Two liquid level gauges installed at a predetermined pitch for detection, a thermometer for measuring the temperature of the liquefied gas in the tank, a liquid level height measured by the liquid level gauge, and a liquid level height at the two locations Then, the amount of change in the volume of the liquefied gas due to receiving or discharging is calculated from the inclination of the tank obtained from the above, the liquid specific gravity is calculated from the temperature of the liquefied gas measured by the thermometer, and the liquid specific gravity is further added to the volume change. And a control means for calculating and outputting the weight of the liquefied gas by multiplying

Further, the present invention provides a flow rate calculating system for calculating a receiving weight or a discharging weight of the liquefied gas when the liquefied gas is received or discharged by the tank lorry. Meter, a goniometer for measuring the inclination of the tank, a thermometer for measuring the temperature of the liquefied gas in the tank, a liquid level height measured by the liquid level gauge and a tilt of the tank measured by the goniometer. Calculate the volume change of the liquefied gas by receiving or discharging from it, calculate the liquid specific gravity from the temperature of the liquefied gas measured by the thermometer, and further calculate the weight of the liquefied gas by multiplying the volume change by the liquid specific gravity And control means for outputting the data.

Therefore, according to the present invention, the volume is calculated from the value measured by the liquid level meter or the goniometer, and the liquid specific gravity is calculated from the liquid temperature measured by the thermometer to calculate the weight. A flow meter for directly measuring the liquefied gas to be discharged is not required, and instead, a flow rate calculation system for a tank truck as a flow rate measuring means can be provided at low cost.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a tank lorry flow calculation system according to the present invention will be described below with reference to the drawings. Although the flow rate calculation system according to the present embodiment is an example of application to the bulk lorry described in the conventional example, this is not limited to the bulk lorry but can be applied to a large tank lorry and the like. The bulk lorry 10 has a tank 12 mounted on the undercarriage of a traveling vehicle 11 and discharges liquefied gas to a valve instrument box 13 and a bulk storage tank provided with a fluid device in the same manner as the bulk lorry 10 shown in FIG. A hose reel box 14 equipped with a discharge hose to be performed is provided. The bulk lorry 10 is provided with a pipe provided with a number of valves and the like for receiving the liquefied gas from the supply terminal into the tank 12 and for supplying the liquefied gas in the tank 12 to the bulk storage tank. FIG. 1 is a diagram showing a tank cross section and a flow path circuit of a bulk lorry.

A safety valve 21 is provided at an upper portion of the tank 12, and a liquid port 22 for supplying liquefied gas and a pressure equalizing port 23 for returning gas stored in the tank 12 are provided at a bottom surface. Emergency shutoff valves 25 and 26 are attached. The liquid port 22 is connected to a coupling 29 via a main valve 27 and a liquid intake valve 28, and the pressure equalizing port 23
The coupling 32 through the main valve 30 and the ventilation valve 31
It is connected to the. The couplings 29 and 32 are both provided in the valve instrument box 13. When the liquefied gas is received, the door of the valve instrument box 13 is opened, and a supply hose extending from the base side for sending the liquefied gas is connected to the coupling 29. Then, a gas hose for returning gas to the base side is connected to the coupling 32.

The bulk lorry 10 is configured to receive a liquefied gas from a base side and to supply the liquefied gas to a bulk storage tank provided in an ordinary household. In the liquid flow path 33 on the liquid port 22 side, a discharge flow path 34 for sending a liquefied gas to a bulk storage tank is formed in a branched manner, and a discharge hose in the hose reel box 14 is provided therethrough via a liquid feed pump 35. 36 are connected. The discharge hose 36
Is wound on a hose reel 37 in the hose reel box 14 and can be extended to a bulk storage tank remote from the bulk trolley 10. On the other hand, the gas flow path 3 on the pressure equalizing port 23 side
8 contains the gas expelled from the bulk storage tank.
A return flow path 39 for returning to 2 is formed, and is connected to a pressure equalizing hose 39 wound around a hose reel 41. In addition, the piping of the bulk lorry 10 is provided with valves and instruments as illustrated in addition to those described above.
Of the valves, those shown in white are normally open and those painted in black are normally closed.

Next, a control section provided in the bulk lorry 10 will be described. The bulk lorry 10 is controlled by a control panel mounted on the cab 15 for driving the liquid feed pump 35, preventing erroneous starting, and calculating and outputting a flow rate which is a feature of the present embodiment. FIG. 2 is a diagram showing a control system centered on the control panel. Therefore, the control panel 50 has a limit switch 5 for checking the state of the parking brake 52 and detecting the opening and closing of the doors of the valve instrument box 13 and the hose reel box 14 in order to prevent erroneous starting during reception and discharge of the liquefied gas.
In response to the signals from the motors 3 and 54, they are connected to an erroneous starting prevention device 55 to perform all-wheel brake locking. Further, a gas detector 56 for detecting gas leakage is provided in the valve instrument box 13 in which a plurality of valves are stored. The control panel 50 is also connected to the gas detector 56, and the control panel 50
An alarm buzzer 57 that issues an alarm by a gas leak signal or the like is attached to itself.

The bulk lorry 10 has a PT
The liquid feed pump 35 is driven by rotation taken out from the O-axis, and a control panel 50 is connected to the engine 58 and the PTO device 59. The liquefied gas is received and discharged by the bulk lorry 10 by opening and closing the liquid intake valve 28, the ventilation valve 31, and the emergency shutoff valves 25 and 26 provided at the liquid port 22 and the pressure equalizing port 23. (See FIG. 1), especially the emergency shutoff valve 2
The opening and closing of the valves 5 and 26 is performed by hydraulic control, and can be opened by operating the hydraulic hand pump 61, and can be closed by controlling the opening and closing of the electromagnetic valve 62. Therefore, the solenoid valve 62 is connected to the control panel 50.

In the present embodiment, the discharge amount of the liquefied gas and the like are not directly measured using a flow meter as in the prior art, but are calculated by an arithmetic processing. for that reason,
The control panel 50 includes a CPU as an arithmetic processing unit, a RAM for temporarily storing data, and a ROM for storing data and a liquefied gas receiving / discharging program to be described later.
A programmable controller (hereinafter, simply referred to as “controller”) 51 for calculating and outputting a flow rate is mounted.

The receiving / discharging program by the controller 51 is performed by calculating the flow rate of the liquefied gas by calculating the change in the capacity in the tank 12. Therefore, in the present embodiment, two liquid level gauges 63 and 64 for measuring the liquid level in the tank 12 for calculating the volume.
Is used. The two liquid level gauges 63 and 64 are attached to the bottom surface of the tank 12 at regular intervals (pitch L). Since the specific gravity of the liquefied gas (eg, LP gas) varies depending on the temperature, a thermometer 6 for measuring the temperature of the liquid in the tank is used.
5 is attached to the bottom surface of the tank 12. The liquid level gauges 63 and 64 and the thermometer 65 are connected to the control panel 50. In order to output the flow rate of the liquefied gas calculated by the controller 51, the control panel 50 is connected to a liquid level display 66 for displaying the capacity and a printer box 67 for displaying and printing the weight. The control panel 50
As described above, each device is connected, and a circuit for controlling each device other than the controller 51 is assembled.

The system for calculating the flow rate of the bulk lorry 10 in this embodiment is constituted by the liquid level gauges 63 and 64 and the thermometer 65 with the controller 51 of the control panel 50 as a main component. The calculation of the volume or weight of the received or discharged liquefied gas is executed according to a liquefied gas receiving / discharging program stored in the controller 51. Therefore, the following calculation formula for executing the liquefied gas receiving / discharging program is stored in the controller 51.

First, the liquid level gauges 63 and 64 are installed at two positions in the longitudinal direction to measure the liquid level because the suspension of the traveling vehicle 11 may sink and the tank 12 may be inclined. is there. If the two liquid level gauges 63 and 64 are used, the inclination θ of the liquid level with respect to the inclined tank as shown in FIG. 1 is determined by the mounting pitch L of the liquid level gauges 63 and 64 and the liquid level heights H1 and H2. You can ask. The pitch L is stored in advance as a fixed value, and the measured liquid level H
1 and H2, the volume is known from the shape and size of the tank 12, so that the volume of the liquefied gas according to the liquid level heights H1 and H2 in the tank 12 can be calculated. Therefore, the controller 51 stores a capacity calculation formula for calculating the capacity of the liquefied gas in consideration of the inclination of the tank 12.

Next, the specific gravity of the liquefied gas varies depending on the temperature, and the temperature-specific gravity relationship also changes depending on the component ratio of the liquefied gas. Therefore, for example, in the case of LP gas,
Since the specific gravity differs depending on the mixing ratio of propane and butane, it is necessary to previously store a calculation formula corresponding to the mixing ratio. FIG. 3 shows a specific example of the relationship between the temperature and the specific gravity. In FIG. 3, the horizontal axis indicates the temperature in degrees Celsius, and the vertical axis indicates the specific gravity. And as an example of LP gas, propane 80%, butane 20
The plotted value of the% molar fraction conversion value is indicated by a broken line. Note that only one example is shown here, but the calculation formula can be completed if the ratio is constant depending on the base, but it is necessary to similarly store the calculation formula for other ratios and liquefied gas. is there. Therefore, a specific gravity calculation formula for calculating the liquid specific gravity from an arbitrary temperature is stored in the controller 51.

Thus, the flow rate calculation system according to the present embodiment
The liquefied gas flow rate at the time of receiving and discharging is calculated by the controller 51 from the capacity calculated by the capacity calculation formula and the specific gravity calculated by the specific gravity calculation formula. Next, the operation of the flow rate calculation system for calculating and outputting the volume and weight of the liquefied gas will be described.

First, a case where the LP gas is supplied from the supply terminal by the bulk lorry 10 having such a flow rate calculation system will be described with reference to the flow chart shown in FIG. Here, the LP stored in the controller 51 is used.
An acceptance program for receiving gas is executed.
The bulk lorry 10 is stopped at a predetermined position where it can be supplied at the LP gas supply terminal, but the controller 51 has not been operated until this time. Therefore, L
When the P gas is received, the switch on the operation panel 68 is turned on and the operation panel 68 is set to a state where the flow rate can be calculated. Then, the ratio of propane gas is selectively input to the displayed selection screen on the operation panel 68 (S11). The selection input corresponds to a calculation formula of the liquid specific gravity stored in advance. Therefore, when the ratio is constant depending on the supply base, the selection here can be omitted.

When a selection input is made, the tank 1
Before the reception of the LP gas into the tank 2, the liquid level heights H 1 and H 2 of the LP gas in the tank 12 are measured by the liquid level gauges 63 and 6.
4 is measured. In the liquid level gauges 63 and 64, when the switch is turned on, the pulse generator is activated, and pulse-like ultrasonic waves are emitted vertically upward from the transmitting ultrasonic transducer,
The light is reflected by the liquid surface of the liquefied gas, returned, received by the receiving ultrasonic transducer, amplified by the amplifier circuit, and detected by the pulse detection circuit. The controller 51 measures the time until the ultrasonic pulse emitted from the transmitting ultrasonic transducer is detected by the pulse detection circuit, and obtains the liquid level height H1 from the relational expression between the preset time and the liquid level. , H2 are calculated. Further, in the controller 51, the initial capacity in the tank 12 is calculated from the relationship with the pitch L according to the capacity calculation formula, and the specific gravity is calculated from the temperature measured by the thermometer 65 by the specific gravity calculation formula. And the weight is calculated, and the capacity and the weight are stored as initial values (S12).

On the other hand, the bulk truck 1 stopped at a predetermined position
In the case of 0, the operator opens the door of the valve instrument box 13, and an LP gas supply hose is connected to the coupling 29 provided there, and a gas hose is connected to the coupling 32 from the base side. After such preparation is completed, the emergency shutoff valve 2 is operated by operating the hydraulic hand pump 61.
5, 26 are opened. At this time, since the solenoid valve 62 that has been open is closed once by the operation start of the controller 51, the emergency shut-off valves 25 and 26 are opened by hydraulic pressure acting. Thereafter, the liquid intake valve 28 and the vent valve 31
Is opened, and LP gas supplied from the base side is
2 and the acceptance starts. The LP gas (liquid) supplied from the base side passes through the liquid flow path 33 to the tank 12.
The gas stored in the tank 12 and stored in the tank 12 is returned from the pressure equalizing port 23 through the gas flow path 38 to the base side as the gas is charged.

The tank 1 is gradually supplied by the supply from the base side.
2 is filled with LP gas, the controller 51
Thus, the calculation of the LP gas receiving weight is performed based on the rising liquid level (S13). For the weight calculation, first, the pitch L of the liquid level gauges 63 and 64 and the liquid level gauges 63 and 6
4, the inclination θ of the tank 12 is calculated from the liquid level heights H1 and H2. Then, the volume of the LP gas filled in the tank 12 is calculated from the slope θ in accordance with the volume calculation formula, and the volume before the start of the reception measured in S12 is subtracted to obtain the LP received in the tank 12 from the base. The gas volume is calculated. Further, since the liquid specific gravity is calculated from the specific gravity calculation formula based on the measurement value from the thermometer 65, the LP received from the value of the calculated capacity and the liquid specific gravity is used.
The weight of the gas is calculated.

In the calculated value, the volume of the LP gas present in the tank 12 is displayed by the liquid level indicator 66 (S14), and the weight of the LP gas received from the base is displayed by the printer box 67. (S15). The calculation of the capacity and the weight is performed according to the calculation speed of the controller 51 used in this embodiment, for example, 3 to
It is repeated in a cycle of 5 seconds, and it is confirmed whether or not the capacity that can be received into the tank 12 is reached each time (S16). Then, when it is confirmed that the LP gas in the filled tank 12 has reached the allowable amount (S16: YE
S), an open signal is sent from the controller 51 to the solenoid valve 62. When the solenoid valve 62 is opened, the emergency shutoff valves 25, 2
6 is released from the hydraulic pressure and closed, and the supply from the base side to the tank 12 is cut off (S17). At this time, the alarm 57
Is activated, the worker is notified of the end of reception by an alarm, and the switch on the operation panel 68 is turned off to complete the reception.

The supply from the base is also stopped, and how much supply has been performed into the tank 12 from the base is
It can be confirmed by the weight of the LP gas displayed on the printer box 67 or printed out. When the receiving is completed, the operator closes the liquid intake valve 28 and the vent valve 31, removes the hose from the couplings 29 and 32, and closes the door of the valve instrument box 13. At this time, the door is securely closed and the limit switch 53 is turned on,
The all-wheel brake lock of the false start prevention device is released. Then, the driver confirms the release of the parking brake 52 and the all-wheel brake lock by the display means in the cab 15, and causes the bulk lorry 10 to travel to a supply destination provided with a bulk storage tank.

Next, a case will be described in which the LP gas thus loaded is discharged from the tank 12 to a bulk storage tank installed in a general household or the like. FIG. 5 shows a bulk lorry 1
It is a flow showing the flow of LP gas discharge from 0 to the bulk storage tank. Therefore, first, the bulk lorry 10 loaded with the LP gas moves to a house provided with a bulk storage tank, and is stopped at a predetermined position where discharge is possible. Since the operation of the controller 51 is stopped during the running, the switch on the operation panel 68 is first turned on and the controller 51 is set to a state where the flow rate can be calculated. And here, controller 5
A discharge program for discharging LP gas (liquid) to the bulk storage tank stored in 1 is executed.

When the controller 51 is turned on,
The liquid level heights H1 and H2 of the LP gas in the tank 12 are measured by the liquid level gauges 63 and 64, and the initial volume in the tank 12 is calculated from the relationship with the pitch L according to the volume calculation formula and stored ( S21). At this time, the capacity in the tank 12 has been calculated by receiving or previously performed filling, but since the capacity in the tank 12 changes due to the heat of the outside air or the like, it is necessary to calculate and store the capacity immediately before the discharge. Because there is. On the other hand, the bulk truck 1 stopped at a predetermined position
In the case of 0, the door of the hose reel box 14 is opened, and the discharge hose 36 and the equalizing hose 39 stored therein are sent out from the hose reels 37 and 41, and the coupling 4 at the tip end.
3 and 44 are connected to a bulk storage tank (not shown). Then, the emergency shutoff valves 25 and 26 are opened by the operation of the hydraulic hand pump 61 in the valve instrument box 13 in the same manner as at the time of reception.
Preparation for gas discharge to the bulk storage tank is completed. At this time, the solenoid valve 62 is closed.

Then, the LP gas is sent out from the tank 12 by driving the liquid feed pump 35, and discharge to the bulk storage tank is started. The drive of the liquid feed pump 35 is started by turning on a remote control switch 69 using wireless communication. When the ON signal from the remote control switch 69 is received by the receiver 70 of the control panel 50, the engine 58 is driven, the electromagnetic clutch of the PTO device 59 is connected to the PTO shaft, and the rotation is taken out therefrom. 3
5 will be driven. When the liquid feed pump 35 is driven, the LP gas in the tank 12 flows out of the liquid port 22, passes through the discharge flow path 34, and further flows from the discharge hose 36 into a bulk storage tank (not shown). On the other hand, the gas stored in the bulk storage tank with the filling of the LP gas is returned from the pressure equalizing hose 42 to the tank 12 through the return flow path 39 and the gas flow path 38, and from the pressure equalizing port 23.

The LP gas in the tank 12 gradually decreases due to the discharge into the bulk storage tank, and the controller 51 calculates the discharge flow rate of the LP gas sent to the bulk storage tank from the descending liquid level. (S2
2). The flow rate calculation is performed based on the pitch L of the liquid level gauges 63 and 64 and the liquid level heights H1 and H2 measured by the liquid level gauges 63 and 64 in the same manner as at the time of receiving the inclination θ of the liquid level with respect to the tank 12.
Is calculated, and the volume of the LP gas remaining in the tank 12 is calculated. Then, the capacity of the LP gas discharged to the bulk storage tank is calculated by subtracting the capacity in the tank 12 from the initial capacity stored in S21. Furthermore, since the liquid specific gravity is obtained based on the measurement value from the thermometer 65, the L discharged to the bulk storage tank is calculated from the calculated discharge capacity and liquid specific gravity.
The discharge weight of the P gas is calculated. Then, the volume of the LP gas remaining in the tank 12 is displayed on the liquid level indicator 66 (S
23), the weight of the LP gas discharged into the bulk storage tank is displayed on the printer box 67 (S24).

Then, it is confirmed whether or not the bulk storage tank has reached the filling capacity based on the discharge capacity from the tank 12 (S25), and the calculation and display of the capacity and weight are also performed by the calculation speed of the controller 51 of the present embodiment. 3-5 according to
It is repeated in a cycle of seconds. So, tank 12
When the discharge capacity calculated from the liquid level in the tank reaches the filling capacity (S26: YES), the driving of the engine 58 is stopped by a signal from the control panel 50, the electromagnetic clutch of the PTO device 59 is also disengaged, and the PTO is released. The rotation of the shaft stops. The driving of the liquid feed pump 35 is stopped to stop the discharge to the bulk storage tank, and at the same time, an open signal is sent from the controller 51 to the solenoid valve 62. Therefore, the solenoid valve 62 opens and the emergency shutoff valve 2
5, 26 are closed and the discharge to the bulk storage tank is interrupted (S
26). At this time, the alarm 31 is activated, the operator is notified of the completion of the filling by an alarm, and the operation panel 68 is turned off to complete the discharge.

The amount of discharge from the tank 12 to the bulk storage tank can be displayed on the printer box 67 or can be confirmed by the weight of the LP gas printed and ejected. When the discharge is completed, the trader removes the couplings 43 and 44 from the bulk storage tank and rewinds the discharge hose 36 and the equalizing hose 39 to the hose reels 37 and 41. Then, the doors of the valve instrument box 13 and the hose reel box 14 are closed, but when the doors are securely closed and the limit switch 53 is turned on, the all-wheel brake lock of the erroneous starting prevention device is released. Thereafter, the driver confirms the release of the parking brake 52 and the all-wheel brake lock by the display means in the cab, and drives the bulk lorry 10 to the next filling destination provided with the bulk storage tank.

Therefore, according to the flow rate calculation system of this embodiment, the flow rate (weight) at the time of receiving or discharging the liquefied gas is calculated using the measured values of the liquid level gauges 63, 64 and the thermometer 65. As a result, the expensive flow meter could be eliminated. In addition, the elimination of the flow meter eliminates the need to pass the liquefied gas through a thin tube, thereby eliminating the problem that gas is generated and causes malfunction or erroneous display. Conventionally, only the flow rate at the time of discharge to the bulk storage tank was measured by a flow meter. However, according to this flow rate calculation system, the flow rate at the time of receiving from a base can also be confirmed.

In the above embodiment, the inclination θ of the tank 12 is obtained by using the two liquid level gauges 63 and 64. However, the inclination θ of the tank 12 is measured by the goniometer. In this case, even when one liquid level gauge is used, the inclination θ measured by the goniometer and the liquid level height at a specific position measured by the liquid level gauge determine the liquefied gas corresponding to the liquid level height. The capacity can be calculated. Therefore, the same effect can be obtained even if the flow rate calculation system of the bulk lorry 10 of the above embodiment is configured to include the angle gauge as well as the liquid level gauge and the thermometer with the controller 51 of the control panel 50 as the main. .

[0034]

According to the present invention, the change in the volume of the liquefied gas due to receiving or discharging is calculated from the liquid level and the inclination of the tank, the liquid specific gravity is calculated from the temperature of the liquefied gas, and the liquid specific gravity is further added to the volume change. , The weight of the liquefied gas is calculated and output, so that an inexpensive flow rate calculation system for calculating the flow rate of the liquefied gas at the tank lorry at the time of receiving and discharging the liquefied gas can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing a cross section of a tank and a flow path connected to the tank.

FIG. 2 is a diagram showing a control system of a bulk lorry centering on a control panel.

FIG. 3 is a diagram showing a specific example of a temperature-specific gravity relationship.

FIG. 4 is a diagram showing a flow in a case where LP gas is supplied from a supply terminal.

FIG. 5 is a diagram showing a flow when discharging LP gas from a bulk lorry to a bulk storage tank.

FIG. 6 is a side view showing a bulk truck.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Bulk lorry 12 Tank 13 Valve meter box 14 Hose reel box 15 Cab 35 Liquid feed pump 50 Control panel 51 Controller 62 Solenoid valve 63, 64 Level gauge 65 Thermometer 66 Level indicator 67 Printer box

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuo Murakami 1-1 Term, Sanbonmatsucho, Atsuta-ku, Nagoya F-term in Nippon Shrine Manufacturing Co., Ltd. (reference) 3E083 AA13 AC01

Claims (2)

[Claims] 1. A flow rate calculation system for calculating a receiving weight or a discharging weight of a liquefied gas at the time of receiving or discharging a liquefied gas by a tank lorry, wherein the flow rate calculating system is installed at a predetermined pitch for measuring a liquid level in the tank. Two liquid level gauges, a thermometer for measuring the temperature of the liquefied gas in the tank, a liquid level height measured by the liquid level gauge, and a tilt of the tank obtained from the two liquid level heights Calculate the volume change of the liquefied gas by receiving or discharging from it, calculate the liquid specific gravity from the temperature of the liquefied gas measured by the thermometer, further multiply the volume change by the liquid specific gravity to calculate the weight of the liquefied gas. And a control means for calculating and outputting the calculated value. 2. A flow rate calculating system for calculating a receiving weight or a discharging weight of a liquefied gas when a liquefied gas is received or discharged by a tank lorry, wherein a liquid level gauge for measuring a liquid level in the tank; A goniometer for measuring the inclination of the tank, a thermometer for measuring the temperature of the liquefied gas in the tank, and a receiving or discharging from the liquid level height measured by the liquid level gauge and the inclination of the tank measured by the goniometer. , The liquid specific gravity is calculated from the temperature of the liquefied gas measured by the thermometer, and the volume change is multiplied by the liquid specific gravity to calculate and output the weight of the liquefied gas. A flow rate calculation system for a tank lorry, comprising: a control unit.