JPH0324975B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a level sensor in a fuel supply pipe that is open at one end and communicated with an overflow prevention mechanism valve at the other end so that the internal pressure increases as the liquid level rises. The present invention relates to a tank lorry refueling device that operates a valve with an overflow prevention mechanism in response to an increase in the pressure of the level sensor.

[Prior Art] Generally, when supplying oil to the hatch of a tank truck, the amount of oil to be supplied is usually preset to the capacity of the hatch. To prevent overflow, a level sensor is used to stop the supply of liquid when it reaches the level sensor, thereby preventing overflow.

Although the level sensor can be provided within the hatch, it is generally attached to a supply or drop pipe that is inserted into the hatch. Then, the drop pipe is inserted into the hatch to a predetermined depth to supply oil. When the oil reaches the level sensor, the air inside the sensor is pressurized by the rising oil, and the pressurized air pressure overflows. A valve with a prevention mechanism is activated to stop refueling.

By the way, when the drop pipe finishes refueling,
Since oil drips from the drop pipe and level sensor, they are generally stored upside down. If the sensor is stored upside down, oil adhering to the sensor may block the communication hole to the valve, and if a blocked level sensor is used, the valve will not operate even if the pressure inside the sensor increases. This may lead to an overflow accident. Particularly when the oil being processed is heavy oil, blockages are likely to occur, and improvements in level sensors are desired.

In order to better understand the present invention, the prior art will be further explained with reference to FIGS. 1-3.

A flow meter 2 and a main valve 3 are provided in the middle of a pipe 1 leading to an oil storage tank (not shown in FIG. 1), and the main valve 3 is controlled to open and close by a control device (also not shown). Flow meter 2
The measured flow rate is sent to the control device. A pipe 5 is installed upright from the rack 4, and an in-arm 8 extending horizontally is connected to the pipe 5 via a swivel joint 7.
The out arm 10 is connected via. A valve 12 with an overflow prevention mechanism, the details of which will be described later, is provided at the tip of the out arm 10.
A downwardly extending oil supply pipe, ie, a drop pipe 13, is connected to the tip of the out arm 10.
A level sensor 14 is provided on the drop pipe 13. A canopy 16 is supported by a support 15 erected on the rack 4.
A refueling amount indicator 17 is attached to 6. The elements from the in-arm 8 to the out-arm 10 constitute a loading arm R. Heavy oil is
Compared to gasoline, light oil, etc., bubbles are less likely to be generated during refueling, so there is no need to lengthen the drop pipe 13 and insert it near the bottom of the lorry during refueling. Therefore, the drop pipe for heavy duty is short as shown in the figure, making it easier to insert or pull out the lorry.

By the way, the conventional level sensor 14 has one end 20 open and the other end 21 as shown in FIG.
A sensor tube 22 extends from there. and liquid level
When LV reaches level sensor 14, sensor 14
The inside of the tank is compressed by the rising liquid level, and this pressure operates a control mechanism (not shown) via the sensor pipe 22, and the oil supply is automatically stopped by closing the overflow prevention mechanism valve 12. It's summery. In this case, the control mechanism may use the air pressure from the sensor tube 22 as pilot pressure to operate the overflow prevention valve with another pressurized air source, or it may directly use the air pressure from the sensor tube 22. It can also be used directly to operate a valve with an overflow prevention mechanism.
When using another air source, the air pressure generated in the level sensor 14 is applied to the flexible membrane chamber of the control valve, as described in, for example, Japanese Patent Application Laid-open No. 187675/1987 filed by the present applicant. When the flexible membrane is moved by air pressure, the passage of the valve is switched, the air pressure from the pressurized air source is applied to the actuating device, and the actuating device closes the main valve provided in the oil supply pipe. is preferable.

Now, when refueling is completed as described above, the drop pipe 13 is stored upside down as indicated by the reference numeral 13a in FIG. Then, as shown in FIG. 3, oil droplets 23 of heavy oil adhering to the inner wall of the level sensor 14 fall by gravity toward the bottom of the sensor and accumulate. As a result, the sensor tube 22 is closed. An easy way to prevent blockage is to wipe off the oil droplets inside the sensor with a cloth before storing it upside down, but the sensor is not very large and it is impossible to completely wipe off the oil droplets inside the sensor. , some kind of countermeasure is desired.

[Problems to be Solved] Therefore, an object of the present invention is to provide a fuel supply device having a level sensor in which the communication hole of the sensor is not blocked even when the drop pipe and the level sensor are stored upside down without wiping them. be.

[Means for Solving the Problems] According to the present invention, a level sensor is provided in the oil supply pipe, one end of which is open and the other end communicates with an overflow prevention mechanism valve, and whose internal pressure increases as the liquid level rises. In a tank truck refueling device that operates a valve with an overflow prevention mechanism due to a rise in pressure, a protrusion is provided at the end opposite to the opening, and the overflow prevention mechanism is connected to the valve through a hole provided in the protrusion. It has a level sensor in communication with it.

[Explanation of effects] Therefore, when the liquid level rises and enters the level sensor from the opening of the level sensor, the internal pressure of the level sensor increases, and the air inside the level sensor flows through the protrusion. The water flows from the hole to a valve with an overflow prevention mechanism, which activates the valve and prevents overflow.

After the refueling operation is completed, the refueling pipe is turned upside down and stored, but at that time, the oil adhering to the inside of the level sensor will flow to the side opposite to the opening. however,
Because of the protrusion, oil adhering to the side surface of the level sensor will accumulate around the protrusion when the oil supply pipe is turned upside down, and will not rise to the hole and block the hole.

As described above, according to the present invention, by providing a protrusion on the side facing the opening of the level sensor, an inexpensive level sensor having a blockage prevention function with a simple structure can be obtained, and the work of refueling a tank truck can be performed safely. And it can be done efficiently.

[Example] Examples of the present invention will be described below with reference to FIGS. 4 to 9.

In the embodiment shown in FIGS. 4 and 5, the bottom 21 of the other end of the open end 20 of the level sensor 14 includes:
A protrusion 30 that protrudes inward is provided. A pore 31 is provided in this protrusion 30 so as to penetrate through the bottom 21 . A protrusion 32 is provided on the outside of the bottom portion 21 in alignment with the protrusion 30 .
The sensor tube 22 is inserted into the hole 33 , and the inside of the level sensor 14 communicates with the valve with an overflow prevention mechanism through the sensor tube 22 .

Thus, the bottom of the level sensor is provided with an inwardly projecting protrusion 30 and a slit 3 leading to the valve.
1 is formed on this protrusion 30, an oil reservoir 40 is formed between the bottom 21 and the protrusion 30, and as a result, as shown in FIG.
4 is stored upside down, the oil droplets will be accommodated in the oil reservoir 40 and will not block the protrusion 30, that is, the pore 31.

The embodiment shown in FIGS. 6 and 7 differs from the previous embodiment in that the level sensor 14 is provided inside the drop pipe 13. That is, in the embodiment shown in FIGS. 4 and 5, the level sensor was attached to the outside of the side wall parallel to the drop pipe 13, but in this embodiment, the main body is provided inside the pipe, and the open end 20 is attached to the outside of the drop pipe 13. I want to. The effect is the fourth
Since it is substantially the same as that of the embodiment shown in FIG. 5 and FIG.

The embodiment shown in FIG.
Instead of forming the protrusion 30 on the sensor tube 22
This is an example in which the protruding portion is formed by penetrating the bottom portion 21 and protruding inward, and the oil reservoir 40 is formed between the protruding portion 41 of the sensor tube 22 and the bottom portion 21.
It is easily understood that according to this embodiment, the structure is simpler and cheaper. The embodiment shown in FIG. 9 is an example in which the bottom portion 21 is inclined, the sensor tube 22 is provided upward in the figure, the lower end of the sensor tube 22 is made to protrude to form a protrusion, and an inclined oil reservoir 40 is provided. be.

[Effects of the Invention] As described in detail above, according to the present invention, by simply forming a protrusion on the end opposite to the opening of the level sensor, even if the level sensor is turned upside down after the liquid supply operation is completed, the oil can be maintained. Droplets do not block the sensor and render it inoperable. Therefore, the present invention is more effective when applied to a fuel supply system for heavy oil, which has a strong tendency to solidify when the temperature drops. In other words, since heavy oil is generally kept warm, it enters the sensor pipe, but once the heavy oil has entered the sensor pipe and is left to cool and solidify, it is difficult to drain it out.However, according to the present invention, entry is completely prevented. Therefore, there are no problems such as those mentioned above, and it is highly effective when applied to the handling of heavy oil. Therefore, the workability of the oil supply device is improved.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an example of a refueling device to which the present invention is applied, Fig. 2 is a front view showing an example of a conventional level sensor, and Fig. 3 is a front view showing an example of a conventional level sensor. FIG.
FIG. 5 is a partially cross-sectional front view of an embodiment of a level sensor embodying the present invention, FIG. 5 is a diagram showing a drop pipe facing upward, and FIG. FIG. 7 is a diagram similar to FIG. 5 of the embodiment shown in FIG. 6, FIG. 8 is a diagram similar to FIG. 4 showing another embodiment, and FIG. 9 is a diagram similar to FIG. 8 is a diagram similar to FIG. 5 of the embodiment shown in FIG. 8; 12... Valve with overflow prevention mechanism, 13...
...Drop pipe, 14...Level sensor, 20
...open end, 21...bottom, 22...sensor tube,
30...Protrusion, 40...Oil pool.

Claims (1)

[Claims] 1. A level sensor is installed in the oil supply pipe, one end of which is open and the other end communicates with the overflow prevention mechanism valve, and the internal pressure increases as the liquid level rises, and the overflow prevention mechanism valve is actuated by the increase in pressure of the level sensor. In the refueling system for tank trucks,
1. A refueling device comprising: a protrusion provided at an end facing the opening; and a level sensor communicated with a valve with an overflow prevention mechanism through a hole provided in the protrusion.