JPS5934596B2 - Liquid level control method during refueling - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to a liquid level control method when refueling a tank at a gasoline filling station from a tank truck.

In recent years, gasoline filling stations have begun using tanker trucks to avoid releasing gasoline vapor into the atmosphere, which leads to pollution.
Currently, when refueling an underground tank, it is sealed from the outside and the gasoline vapor in the underground tank is collected into a tank truck. However, monitoring the liquid level gauge required manpower, and there was a risk of gasoline overflowing due to insufficient monitoring.

Therefore, the present invention automatically senses when the liquid level in the tank reaches a predetermined level and stops refueling to prevent gasoline from overflowing, allowing safe refueling without the need for human supervision. The purpose of this invention is to provide a method for controlling the liquid level during refueling.

Next, an illustrated embodiment of the present invention will be described.

First, let's talk about the equipment used in this example method. 1 is an underground tank buried under the ground 2 of a gasoline filling station, 3 is a fuel pipe with one end connected to the top of the underground tank 1, and the other end connected from the ground 2. It stands out.

4 is a liquid level sensing tube attached to the underground tank 1 with its lower end facing the required level in the underground tank 1, and its upper end facing the ground 2.

5 is the tank of tank truck 6, 7 is tank truck 6
The auto-stop valve installed in the tank is connected to the lower part of the tank 5 through a connecting pipe 9, and its outlet 10 is connected to a refueling hose 11, and the tip of the refueling hose 11 and the refueling pipe 3
are connected by a pair of couplings 12.

13 is a float valve mounted on tank truck 6,
An upper chamber 18 is provided above a float chamber 16 containing a float 15 having a valve 14 via a valve seat 17. A siphon tube 19 is connected to the float chamber 16, and the other end of the siphon tube 19 is connected to the float chamber 16. pair of couplings 20
is connected to the liquid level sensing tube 4, and a tube 21 is connected to the upper chamber 18.
and a control pipe 22 are connected, the other end of the control pipe 22 is connected to a control section 23 (to be described later) of the auto-stop valve 7, the other end of the pipe 21 is connected to the tank 5, and the pipe 21 is connected to a control section 23, which will be described later, of the auto-stop valve 7. A vacuum pump 24 is provided.

The auto stop valve 7 is mainly shown in FIGS. 2 and 3.
As shown in the figure, a valve seat 26 is provided in the body 25 having the inlet 8 and outlet 10 at the left and right ends, and the valve stem 2 is located in the body 25 to the left of the valve seat 26.
7, and the valve seat 26 corresponds to the valve seat 26.
8 into the valve stem 27, and the spherical pilot valve 29 housed in the valve stem 27 is inserted into the menpulp 28.
Corresponding to the pilot valve seat 30 provided in the center, a spring 32 is stretched between the inner flange 31 provided at the inlet 8 and the valve stem 27, and the pilot valve 29 is abutted against the pilot valve seat 30 to open the menpulp 28. A rod insertion hole 33 is provided in the center of the valve seat 28, which abuts against the valve seat 26, and a small pilot hole 33 is provided in the center of the valve seat 28, and a pilot hole 33 is provided in the center of the valve seat 28. A control section 23 is provided at the lower center of 25.

The control unit 23 slides the left-right bushing rod 35 into the body 25 and connects it to a small diameter portion 36 at the left end of the bushing rod 35.
into the loft insertion hole 33, and the stem 38 is slid into the deep hole 37 made at the right end of the butshrott 35, and the groove 3 is formed on the lower surface of the butshrott 35 and the lower surface of the stem 38, respectively.
9.40, a weak spring 41 is stretched between the inner bottom of the deep hole 37 and the stem 38, and a diaphragm 43 is interposed in the lower part of the opening of the diaphragm accommodating portion 42 provided in the body 25, and a diaphragm cap 44 is installed. is fixed, a spring 45 is stretched between the lower surface of the diaphragm 43 and the diaphragm cap 44, and a U-shaped diaphragm stem 46 is installed at the center of the upper surface of the diaphragm 43. A parallel pin 48 is inserted into the long hole 47, the pin 48 is engaged with the groove 39, 40, and the spring 41 moves the pin 48 to the right end of the long hole 47 through the groove 40, and the stem 38 is moved to the right. Further, the control unit 23 brings an L-shaped lever 50, which is pivotally connected to the body 25 by a pin 49, into contact with the right end of the stem 38, and engages the tip of the lever 50 in the operating position of the lever 50, which will be described later. A matching trigger 51 is pivotally connected to the body 25 with a pin 52,
The trigger spring 53 supported on the pin 52 is attached to the body 2.
5 and the trigger 51, and the control tube 22 is connected to a negative pressure control hole 55 formed in the diaphragm cap 44 via a nipple 54 provided in the body 25.

Therefore, in this method, when refueling the underground tank 1 by the tank truck 6, the lever 50 of the auto-stop valve is activated.
is rotated about the pin 49 as a fulcrum as shown by the imaginary line in FIG. 3, and the trigger 51 is engaged with the lever 50 at the rotated position, while the vacuum pump 24 is driven once.

Then, the rotation of the lever 50 pushes the stem 38 to the left as shown in FIG.
Push the bush loft 35 to the left through the bush loft, and move the pilot valve 29 to the left together with the valve stem 27 against the tension of the spring 32 using the small diameter portion 36 of the bush loft to open the pilot valve 29. At the stage where the Butschlot 35 has moved a little to the left, the Butschlot 35 moves the Mempulp 28 to the left and performs the opening operation.

As a result, the gasoline that had previously reached the inlet 8 of the auto-stop valve from the tank 5 of the tank lorry via the connecting pipe 9 flows down by gravity and passes through the menpulp 28.
The oil is injected into the underground tank 1 through the pilot valve 29, the small hole 34, the outlet 10, the oil supply hose 11, and the oil supply pipe 3 in this order.

Also, at this time, due to the operation of the vacuum pump 24,
Gasoline vapor in the underground tank 1 is detected by a liquid level sensing pipe 4, a siphon pipe 19, a float valve 13, and a vacuum pump 2.
4 into the tank 5 of the tank truck, and prevents the vapor pressure in the underground tank 1 from increasing, which tends to increase due to the refueling, thereby facilitating the refueling.

When the liquid level 56 in the underground tank 1 rises due to the refueling and reaches a predetermined level at the lower end of the liquid level sensing tube 4 as shown in FIG. 1, gasoline is sucked up from the liquid level sensing tube 4 and the float valve The water accumulates in the float chamber 16 of 13, which pushes up the float 15 by buoyancy and closes the float valve 13.

Due to the closing operation of the float valve 13 and the subsequent operation of the vacuum pump 24, the vacuum pump 24 is communicated through the pipe 21, the upper chamber 18 of the float valve, the control pipe 22, and the negative pressure control hole 55. The inside of the diaphragm cap 44 becomes negative pressure, and as shown in FIG. 5, this negative pressure causes the diaphragm 43 to be pulled down against the tension of the spring 45, and the pin 48 is pulled down via the diaphragm stem 46, causing the stem to It comes off from the groove 40 of 38.

As a result, the menpulp 28 and the pilot valve 29, which had been pushed to the left by the Butschrodt 35,
pushes Butschrodt 35 to the right due to the supplied oil pressure and the bending reaction force of the spring 32, which causes the weaker spring 4 to move.
1 and move the pin 48 back to the right along the elongated hole 47, and in the opposite manner to the above, the main valve 28 is closed, the pilot valve 29 is closed, and the supply of fuel from the tank 5 to the underground tank 1 is stopped. Ru.

After this stop, the operation of the vacuum pump 24 is stopped, and the oil supply hose 11 is connected to the couplings 12 and 20, respectively.
At the same time, the liquid level sensing tube 4 and the siphon pipe 19 are separated, and the refueling hose 11 and the siphon pipe 19 are separated.
The tank lorry 6 is moved by loading the side thereof onto the tank lorry 6.

Further, in order to change the auto-stop valve 7 from the state shown in FIG. 5 to the initial state shown in FIG.
1 is disengaged from the lever 50 and externally rotated by the trigger spring 53, so that the lever 50 becomes rotatable, so that the stem 38 is moved back to the right by the spring 41.
The concave groove 40 faces the pin 48 position, while the diaphragm 43
When the effect of the negative pressure is removed, the pin 48 is pushed up by the spring 45 via the diaphragm stem 46 and engaged with the groove 40, returning the printing plate to its initial state.

Further, on the upper side, as mentioned above, the pilot valve 29 is opened by the small diameter portion 36 of the bushland, and then the menpulp 28 is opened by the bushschrodt 35, so when the menpulp 28 is operated, the pressure on the left end surface of the menpulp 28 decreases a little. , for this reason, the menpulp 28 by the lever 50
The opening operation can be performed easily, and Menpulp 28
During the closing operation, the pilot valve 29 closes after the main valve 28 is closed, so the water hammer effect accompanying the closing of the main valve 28 is alleviated.

Note that the method of the present invention can be applied not only to underground tanks but also to refueling above-ground tanks.

As described above, the method of the present invention, when refueling a tank by a tank lorry, refuels from the tank lorry to the tank by gravity through an auto-stop valve, while at the same time detecting vapor in the tank from a liquid level sensing tube connected to the tank. The oil is collected in a tank truck through a siphon pipe, a float valve, and a vacuum pump in order, and when the liquid level in the tank reaches a predetermined level, the float valve is closed by the oil in the tank sucked up from the liquid level sensing tube. The automatic stop valve is activated, thereby controlling the control section of the auto stop valve, which is connected in advance to the float valve, to negative pressure and closing the auto stop valve. -It is not only possible to refuel the tank smoothly from the beginning, but unlike pressure-feed refueling, refueling by gravity automatically stops refueling when the liquid level in the tank reaches a predetermined level, allowing gasoline to overflow. Therefore, it is possible to safely refuel a tank from a tank truck under adverse conditions where pressure-feed refueling is not possible due to fire regulations, etc., without requiring human supervision.

[Brief explanation of drawings]

The drawing shows an apparatus used in an example method of the present invention.
Figure 1 is a schematic front view of the auto-stop valve, Figure 2 is a front cross-sectional view of the auto-stop valve, Figure 3 is a plan view of the auto-stop valve, and Figures 4 and 5 are auto-stop in the open and closed states, respectively. FIG. 3 is a front sectional view of the main parts of the valve. 1...Underground tank, 2...Ground, 3.
...Fuel supply pipe, 4...Liquid level sensing pipe, 5...
...tank, 6...tank truck-17.
...Auto stop valve, 8...Inlet, 9...Connection pipe, 10...Outlet, 11
...Refueling hose, 12...Coupling, 13...Float valve, 14...
・Valve, 15...Float, 16...
・Float chamber, 17... Valve seat, 18...
... Upper chamber, 19 ... Siphon tube, 20.
...Cuck; Pulling, 21...Pipe, 2
2... Control tube, 23... Control section, 24
...Vacuum pump, 25...Hotel, 26...Valve seat, 27...
Hartstem, 28...Menpulp, 29...
...Pilot valve, 30...Pilot valve seat, 131...Inner tsuba, 32...
... Spring, 33 ... Hole, 34 ...
...Small hole, 35...Butschlot, 36...
...Small diameter part, 37...Deep hole, 38...
... Stem, 39.40 ... Concave groove, 41 ...
...Spring, 42...Diaphragm housing section, 43...Diaphragm, 44...
...Diaphragm cap, 45...Spring, 46...Diaphragm stem, 47...
...Long hole, 48...Pin, 49...
Pin, 50... Lever, 51... Trigger, 52... Pin, 53... Trigger spring, 54... Nipple, 55...・・・
...Negative pressure control hole, 56...Curved surface.

Claims (1)

[Claims] 1. When refueling the tack with a tank truck, the tank is fed by natural flow from the tank truck through the auto-stop valve, while the steam in the tank is transferred from the liquid level sensing tube connected to the tank to the siphon tube, float valve, and vacuum pump. When the liquid level in the tank reaches a predetermined level, the oil in the tank sucked up from the liquid level sensing tube closes the float valve. A liquid level control method during refueling, characterized in that the auto stop valve is closed by controlling a control section of the auto stop valve to which it is connected by negative pressure.