JPS6010954B2 - Refueling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel supply device for supplying liquid fuel in an underground tank to the wheels of an automobile or the like.

Generally, this type of refueling system is configured to pump up liquid fuel (for example, gasoline) from an underground tank and supply it to the wheels via a flow meter and a refueling nozzle.

An air separation device that separates and removes air from the liquid fuel is usually installed in the middle of the piping between the flow meter and the pump. However, although this air separation device can separate and remove a small amount of air mixed in liquid fuel, it does not have the ability to separate and remove a large amount of air.

For this reason, if the liquid fuel in the underground tank runs out and only air is pumped up, or if the seal between the suction pipe inserted into the underground tank and the pump is incomplete, a large amount of air may be pumped out. When the air is sucked into the pump, there is a problem in that the air discharged from the pump is measured by a flow meter, just as if it were measuring fuel, and this measured value is displayed on the display of the refueling device. Ta. In such a case, the amount of fuel is displayed even though it is not actually flowing, which poses not only legal problems but also commercial problems. The present invention provides an oil supply device that solves the above problem, and focuses on the fact that when compressible air is sucked into the piping between the pump and the flow meter, the pressure in this piping decreases. This is characterized in that it is possible to detect a drop in pressure and stop the supply of fluid to the flow meter, thereby preventing air metering.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, a pump 2 driven by a motor 1
A suction pipe 4 whose lower end is inserted into an underground tank 3 is connected to a suction port (not shown).

A flow meter 6 is connected to a discharge port (not shown) of the pump 2 via a pipe 5. 7 is a display section of the flowmeter 6 provided on the front of the case 8. A strainer 9 is connected in the middle of the pipe 5, as shown in detail in FIG. 2, for removing dust and the like contained in the fuel discharged from the pump 2 and for growing air bubbles in the fuel.

This strainer 9 is connected to an air separation device 10 that separates the air grown by the strainer 9 from the fuel that flows out in the form of bubbles together with this air. This separated air is discharged to the outside through a pipe (not shown). A pipe 11 for returning the fuel condensed in the air separation device 10 into the suction pipe 4 is connected between the air separation device 10 and the suction pipe 4. A pressure receiving path 13a (FIG. 3) of a pressure switch 12 that detects the pressure inside the pipe 5 is connected to the middle of the pipe 5 between the strainer 9 and the flow meter 6. This pressure switch 12 is composed of a pressure detection device 13 and a limit switch 14 having a normally open contact 14a (FIG. 4). Under normal conditions when the pipe 5 is full of fuel, the rod 15 of the pressure detection device 13 is closed. Limit switch 14
The normally open contact 14a of the limit switch 14 is closed by pressing the sensing lever 14b. The pressure detection device 13 is the third
As shown in the figure, a diaphragm 16 that divides the inside of the main body 13b into a pressure receiving passage 13a and a spring chamber 13c, the rod 15 that is slidably held in the main body 13b and has one end fixed to the diaphragm 16, and the diaphragm 16 are It is constituted by a spring 17 that biases toward the pressure receiving path 13a side. 14c is a switch piece of the IJ mitt switch 14 for closing the normally open contact 14a.

The base end of a refueling hose 19 having a refueling nozzle 18 attached to its tip is connected to the outflow side of the flow meter 6 .

20 is a nozzle hook fixed to the side surface of the case 8.

21 is a rod slidably held in this case 8;
It is biased to the outside of the case 8 by a spring (not shown). The inner end of this rod 21 is in close contact with a sensing lever 22a of a limit switch 22 mounted inside the case 8. This IJ mitt switch 22 is provided so that a sensing lever 22a closes its contact 22c (FIG. 4) by pushing a switch piece 22b. Next, the electrical connection between the motor 1 and the IJ mitt switches 14 and 22 will be explained with reference to FIG.

Lead lines 23, 24, and 25 from a three-phase AC power source are connected to the motor via a normally open contact 26a of an electromagnetic switch 26. The coil 26b of the electromagnetic switch 26 and the limit switches 14 and 2 are connected to the lead-in wires 23 and 24.
The two contacts 14a and 22c are connected in series. 27
is a saddle point of a manual switch (not shown), and this contact 27 is connected in parallel with the contact 14a between the coil 26b and the contact 22c.

The operation of the oil supply device having such a configuration will be explained.

When the refueling nozzle 18 is in the nozzle hooked state, the contact 22c of the limit switch 22 is open and the normally open contact 26a of the electromagnetic switch 26 is open, so the motor 1 is stopped. In this case, the pressure inside the pipe 5 is maintained at a predetermined oil pressure due to the previous oil supply. Therefore, in this case, the rod 15 of the pressure switch 12 is held in a state displaced to the left in the figure against the spring 17, and the sensing lever 14
b is pressing the switch piece 14c. This closes the normally open contact 14a. When the refueling nozzle 18 is removed from the nozzle hook 20 in this state, the rod 2
1 is displaced to the right in the figure by a spring (not shown), and the sensing lever 22a of the limit switch 22 is moved to the switch piece 2.
2b.

This closes its normally open contact 22c, causing the coil 26
A current flows through b and is excited, the normally open contact 22a is closed, the motor rotates, and the pump 2 is operated. When the pump 2 operates to operate the fuel nozzle 18, liquid fuel in the underground tank 3 is pumped up and fed to the fuel nozzle 18 under pressure. If a small amount of air is sucked into the pump 2 for some reason during refueling, the air discharged from the pump 2 is separated and removed from the fuel by a strainer 9 in the middle of the pipe 5 and an air separation device 10.

Further, when a large amount of air is sucked into the pump 2, the strainer 9 and the air separation device 10 cannot completely remove the air, and this air flows into the pipe 5 between the flow meter 6 and the strainer 9. do. In this case, unlike liquid, air is compressible, so the pressure inside the pipe 5 does not rise to a predetermined oil supply pressure. As a result, the diaphragm 16 and rod 15 of the pressure switch 12 are integrally displaced to the right in the figure by the spring 17, the sensing lever 14b of the limit switch 14 is separated from the switch piece 14c, and its normally open contact 14a is opened. When the normally open contact 14a opens, current no longer flows through the coil 26b of the electromagnetic switch 26, and the normally open contact 26a opens. Then, the motor 1 is stopped, and the supply of fluid to the flow meter 6 is stopped. After the faulty part is repaired, the pressure in the pipe 5 does not reach the predetermined oil supply pressure, so that the normally open contact 14a of the limit switch 14 is open so as not to inhale air.

Therefore, after removing the refueling nozzle 18 from the nozzle hook 20, by pressing a manual switch (not shown), the coil of the electromagnetic switch 26 is energized, its normally open contact 26a is closed, and the motor 1 is operated. Pump 2 is activated by motor 1.
rotates, and the pressure inside the pipe 5 is maintained at a predetermined oil supply pressure.
The pressure switch 12 senses this and its normally open contact 14a
remains closed. In the embodiment described above, the pressure switch 12 using the diaphragm 16 and the mitt switch 14 is used to detect the pressure inside the pipe 5 and open/close the contact 14a shown in FIG. There is no need to use a pressure switch in the configuration;
It may be a pressure switch 29 using the piston 28 shown in the figure, a pressure switch 31 using the Bourdon tube 30 shown in FIG. 6, or a pressure switch 33 using the bellows 32 shown in FIG. It may be.

In FIGS. 5 to 7, 34, 35, 36 are contacts of each pressure switch 29, 31, 33, 37, 38, 39
is a pressure receiving path of each pressure switch 29, 31, 33. Further, in the embodiment, the pressure inside the pipe 5 is detected and the contact 14a is turned on and off to turn the motor on and off.
F control and prevent the supply of air to the flow meter 6. However, it is not necessarily necessary to control the motor 1 to achieve this purpose, and a solenoid valve is installed in the middle of the piping 5 to prevent the supply of air to the flow meter 6. Turning the valve ON and OFF using the pressure switch,
It may be configured to directly stop the supply of air to the flowmeter.

Furthermore, the reduced pressure inside the pipe 5 is detected and the contact 14a is opened.
ON turns OFF, and with this ON or OFF signal,
It is also possible to directly stop the refueling by applying a current to the solenoid to make a pin or the like protrude so that the refueling nozzle 18 does not come off the nozzle hook 20. It may be configured so that it cannot be lowered downward, so that the refueling can be directly stopped, or alternatively, it may be configured to sound an alarm, display a sold-out or malfunction message, etc. It is also possible to have the worker indirectly stop the refueling.

Further, in this embodiment, a stationary oil supply system has been described, but the present invention is not limited to this, and can also be applied to a ceiling-suspended type oil supply system as shown in FIG.

As explained above, the present invention is configured so that a pressure drop in the piping between the pump and the flow meter is detected by a pressure switch and the supply of fluid to the flow meter is stopped. If a large amount of air is fed into the piping, the pressure inside the piping will drop and the supply of air to the flowmeter can be immediately stopped.

Therefore, even if a large amount of air is fed into the piping, it is possible to prevent air metering.

[Brief explanation of the drawing]

Fig. 1 is a piping diagram showing one embodiment of the oil supply device of the present invention;
The figures are an enlarged sectional view of the strainer and air separation device shown in Fig. 1, Fig. 3 is an enlarged partial sectional view of the pressure switch shown in Fig. 1, and Fig. 4 is an electric circuit diagram used in the present invention. 5
6 and 6 are drawings showing other examples of the pressure switch used in the present invention, FIG. 7 is a side view showing another example of the pressure switch used in the present invention, and FIG. 8 is the oil supply device of the present invention. It is a piping diagram showing another example. 1... Pump, 3... Underground tank, 5... Piping, 6...
...Flowmeter, 12, 29, 31, 33...
Pressure switch, 13a, 37, 38, 39...
Pressure receiving path, 18...Refueling nozzle. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] 1. In a refueling system that supplies fuel from a refueling nozzle via a pump that pumps up fuel in an underground tank or a flow meter, a pressure switch is installed in the piping connecting the pump and the flow meter to detect the pressure inside the piping. Connect the pressure receiving path,
A refueling device characterized in that the supply of fluid to the flow meter is stopped in response to a signal from the pressure switch when the pressure in the pipe is below a predetermined value.