JPH07102878B2 - Refueling device for oil storage tank - Google Patents

Description

TECHNICAL FIELD The present invention relates to a refueling device for an oil storage tank installed underground in a gas station such as a gas station.

[Prior Art] In a conventional oil storage tank, an inflow pipe through which oil flows down to the oil storage tank was directly connected to an oil supply pipe connected to a Lori oil supply hose.

Therefore, when the space of the oil storage tank is 1 kl, for example,
If you accidentally connect a lorry hatch, for example, 2 kl, and unload it, oil will overflow from the oil storage tank. This is dangerous and the spilled oil is wasted.

In general, various techniques for preventing overflow when supplying liquid to a tank or the like are known, and are disclosed in, for example, JP-A-62-28395 and JP-A-56-48992. However, these known techniques have a complicated structure as a whole. The reason is that the unloading work from the lorry causes a relatively large amount of oil to flow per unit time, so a relatively large amount of energy is required when controlling the refueling work by opening and closing the valve.

[Problem to be solved] Therefore, an object of the present invention is to provide a replenishing device for an oil storage tank having a simple structure and capable of reliably closing the main valve by a signal from the float valve to prevent overflow when the tank is full.

[Means for Solving the Problems] According to the present invention, in a refueling device for an oil storage tank installed underground in a gas filling station, an inflow pipe extending from the oil storage tank has a main valve biased toward the valve closing side by a spring. A fluid pressure chamber is formed in the housing in the valve opening direction of the main valve, the fluid pressure chamber being connected to the lubrication pipe through the housing, and the fluid pressure chamber being a passage having an inlet and a throttle of the housing connected to the lubrication pipe. And a pilot pipe communicating with the hydraulic chamber, which is provided in the oil storage tank via a check valve and is closed when the oil level in the oil storage tank rises to the full tank position. Further, the oiling pipe and the inflow pipe are connected by a small-diameter bypass passage.

[Explanation of action and effect] The float valve is open until the oil level reaches the full tank position. Therefore, the oil that has flowed into the oil injection pipe flows into the hydraulic chamber through the passage having the throttle, but due to the throttle, the flow rate is small, and the float valve flows from the hydraulic chamber through the pilot pipe having the check valve. There is more flow out of the.
Therefore, the hydraulic chamber becomes negative pressure, the main valve opens, and the oil flows from the inflow pipe into the oil storage tank.

When the oil tank is full, the float valve closes. Then, since the oil does not flow out from the hydraulic chamber, the pressure in the hydraulic chamber increases and the main valve closes. When the main valve of the lorry is closed after this state and the oil supply hose is removed from the lorry, the oil in the oil supply pipe flows out into the oil storage tank through the bypass passage.

As described above, according to the present invention, the valve housing is provided between the oil supply pipe and the inflow pipe, and the hydraulic chamber and the float valve are connected by the pilot pipe via the check valve. The valve can be closed to prevent overflow. Moreover, since the oil remaining in the oil supply pipe after the main valve is closed flows out into the oil storage tank from the bypass passage, there is no problem of residual oil treatment. Furthermore, since operation from the outside and energy from the outside are completely unnecessary, it is energy-saving, requires only inspection and maintenance, and is easy to work.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, an inflow pipe 2 is attached to an underground oil storage tank 1, and an oil injection pipe 3 is connected to the inflow pipe 2 via a main valve device indicated by reference numeral 30. The main valve device 30 is housed in the manhole cylinder 5, and a lid 6 is provided at the opening of the manhole cylinder 5.

The housing 31 of the main valve device 30 has an inlet 12, an outlet.
13 are formed. The outflow port 13 is connected to the inflow pipe 2, and the inflow port 12 is connected to the oil supply pipe 3. Also,
A valve seat 14 is formed at the edge of the outflow port 13, and the oil injection pipe 3 side and the inflow pipe 2 side are connected by a small-diameter bypass passage 15 that bypasses the valve seat 14.

A main valve 33 is seated on the valve seat 14 and is biased by a spring 34 in the valve closing direction. The hydraulic chamber 35 provided on the valve opening side of the main valve 33 is connected to the inflow port 12 by a passage 37 in which a variable orifice 36 forming a throttle is interposed, but instead of the variable orifice 36, a fixed throttle is used. It may be provided. In addition, a pilot pipe 39 with a check valve 38 for stopping the reverse flow of oil into the hydraulic chamber 35
It is connected to the. This pilot pipe 39 is extended to a full tank position in the underground oil storage tank 1, and at its lower end,
A float valve, generally indicated at 40, is provided.

In FIG. 2 and FIG. 3, the main body 41 of the float valve 40 is provided with an inlet part 42 projecting laterally, and the elbow part of the pilot pipe 39 is shown.
It is rotatably attached to 39a via a swivel 43. The body 41 is made of a lightweight plastic material, and the through hole 45 and
A triangular float portion 46 orthogonal to the through hole portion 45 is formed, and a through hole 47 is formed in the through hole portion 45 in the longitudinal direction.

The through hole 47 communicates with the pilot pipe 39 through the inlet portion 42, and the outlet portion 48 is formed on the side facing the float portion 46. A steel ball 49 is housed in the through hole 47. Therefore, when the float part 46 does not detect the liquid surface, as shown in FIG.
With the weight of, the passage 47 stands upright and the exit 48 is open. On the other hand, as shown in FIG. 3, when the float portion 46 detects the liquid surface and floats, the body 41 rotates around the swivel 43, and when the outlet portion 48 of the through hole 47 becomes lower, the steel ball 49 moves. Then, the outlet 48 is closed.

At the time of oil filling, the float valve 40 does not detect the liquid surface and the opening 48 is open until it reaches the full tank position (Fig. 2).
Therefore, the amount of oil flowing out of the hydraulic chamber 35 via the float valve 40 is larger than the amount of oil throttled by the variable orifice 36 and flowing in from the passage 37. Therefore, the hydraulic chamber of the main valve device 30
The liquid pressure in 35 is low, and the oil pushes up the main valve 33 to open it, and flows into the inflow pipe 2. Float valve 40 detects the liquid level and opens
When the valve 48 is closed (Fig. 3), the outflow of oil from the hydraulic pressure chamber 35 is stopped, and the hydraulic pressure in the hydraulic pressure chamber 35 of the main valve device 30 becomes high, so that the main valve
33 closes. After this state, when the main valve of the lorry is closed and the oil supply hose is removed from the lorry, the oil in the oil supply pipe 3 flows out from the bypass passage 15 into the oil storage tank 1. The float valve 40 is provided at a full tank position below the tank where the oil tank is completely filled so that the oil in the oil filling pipe 3 can flow in. Further, the check valve 38 prevents the pilot pipe 39 from sucking the air in the oil storage tank 1 into the hydraulic chamber 35 due to a negative pressure on the inflow pipe 2 side during the lubrication, and the main valve 33 is closed. It plays the role of preventing movement.

[Effects of the Invention] As described above, the present invention has the following excellent effects.

(I) With a simple structure, the main valve can be reliably closed when the tank is full.

(Ii) After the main valve is closed, the residue in the oil injection pipe flows out into the oil storage tank through the bypass pipe, so no residue treatment is required.

(Iii) There is no external operation, and work is easy and reliable.

(Iv) It does not require external energy and is energy-saving, so there are few failures.

(V) Even if the inflow pipe 2 side becomes negative pressure due to the check valve of the pilot pipe, negative pressure is not applied to the hydraulic chamber, and the operation is reliable.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of the present invention, and FIGS. 2 and 3 are a side cross-sectional view and a cross-sectional view of the float valve when they are opened and closed, respectively. 1 ... Oil storage tank, 2 ... Inflow pipe, 3 ... Lubrication pipe, 15 ...
… Bypass passage, 30 …… Main valve device, 31 …… Housing,
35 …… hydraulic chamber, 36 …… throttle (variable orifice), 37 ……
Passage, 38 ... Check valve, 39 ... Pilot pipe, 40 ... Float valve

Claims (1)

[Claims] 1. In a refueling device for an oil storage tank installed underground in a gas filling station, an inflow pipe extending from the oil storage tank is connected to an oil supply pipe through a housing having a main valve biased toward a valve closing side by a spring. A hydraulic chamber is formed in the housing in the valve opening direction of the main valve, and the hydraulic chamber communicates with an inflow port of the housing connected to the oiling pipe through a passage having a throttle, In addition, a pilot pipe, which is provided in the oil storage tank via a check valve and is closed when the oil level in the oil storage tank rises to a full tank position, is connected to the hydraulic chamber, and a pilot pipe communicating with the float valve is further connected. A refueling device for an oil storage tank, characterized in that it is connected to a pipe by a small-diameter bypass passage.